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1.	A. da Cruz, Márcia G., et al. (författare) Electrochemical Depolymerization of Lignin in a Biomass-based Solvent 2022 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 15:15 Tidskriftsartikel (refereegranskat)abstract Breaking down lignin into smaller units is the key to generate high value-added products. Nevertheless, dissolving this complex plant polyphenol in an environment-friendly way is often a challenge. Levulinic acid, which is formed during the hydrothermal processing of lignocellulosic biomass, has been shown to efficiently dissolve lignin. Herein, levulinic acid was evaluated as a medium for the reductive electrochemical depolymerization of the lignin macromolecule. Copper was chosen as the electrocatalyst due to the economic feasibility and low activity towards the hydrogen evolution reaction. After depolymerization, high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy revealed lignin-derived monomers and dimers. A predominance of aryl ether and phenolic groups was observed. Depolymerized lignin was further evaluated as an anti-corrosion coating, revealing enhancements on the electrochemical stability of the metal. Via a simple depolymerization process of biomass waste in a biomass-based solvent, a straightforward approach to produce high value-added compounds or tailored biobased materials was demonstrated.
2.	Abdel-Magied, Ahmed F., et al. (författare) Chemical and Photochemical Water Oxidation Mediated by an Efficient Single-Site Ruthenium Catalyst 2016 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 9:24, s. 3448-3456 Tidskriftsartikel (refereegranskat)abstract Water oxidation is a fundamental step in artificial photosynthesis for solar fuels production. In this study, we report a single-site Ru-based water oxidation catalyst, housing a dicarboxylate-benzimidazole ligand, that mediates both chemical and light-driven oxidation of water efficiently under neutral conditions. The importance of the incorporation of the negatively charged ligand framework is manifested in the low redox potentials of the developed complex, which allows water oxidation to be driven by the mild one-electron oxidant [Ru(bpy)(3)](3+) (bpy = 2,2'-bipyridine). Furthermore, combined experimental and DFT studies provide insight into the mechanistic details of the catalytic cycle.
3.	Abdelaziz, Omar Y, et al. (författare) Lignin Depolymerisation under Continuous-Flow Conditions : Highlights of Recent Developments 2020 Ingår i: ChemSusChem. - : Wiley. - 1864-564X .- 1864-5631. ; 13:17, s. 4382-4384 Tidskriftsartikel (refereegranskat)abstract Lignin is a poly-aromatic polymer contained in the plant cell wall, and it is considered the most abundant non-carbohydrate polymer on Earth. The aromaticity and richness of its functional groups render lignin an attractive starting biomacromolecule for conversion into a variety of value-added products. The development of successful strategies for lignin valorisation infers the design of effective depolymerisation protocols. Most research on lignin depolymerisation have focused on batch-mode processing, whereas only a few studies have tackled such lignin transformation in continuous reactor systems. In the present paper, we highlight the emerging developments within the concept of continuous lignin processing and the challenges remaining in realising the efficient valorisation of lignin using this technology concept. A special focus is set on the hydrothermal conversion of technical lignin under continuous-flow conditions, together with suggestions for future research.
4.	Abdelaziz, Omar Y., et al. (författare) On the Oxidative Valorization of Lignin to High-Value Chemicals : A Critical Review of Opportunities and Challenges 2022 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 15:20 Forskningsöversikt (refereegranskat)abstract The efficient valorization of lignin is crucial if we are to replace current petroleum-based feedstock and establish more sustainable and competitive lignocellulosic biorefineries. Pulp and paper mills and second-generation biorefineries produce large quantities of low-value technical lignin as a by-product, which is often combusted on-site for energy recovery. This Review focuses on the conversion of technical lignins by oxidative depolymerization employing heterogeneous catalysts. It scrutinizes the current literature describing the use of various heterogeneous catalysts in the oxidative depolymerization of lignin and includes a comparison of the methods, catalyst loadings, reaction media, and types of catalyst applied, as well as the reaction products and yields. Furthermore, current techniques for the determination of product yields and product recovery are discussed. Finally, challenges and suggestions for future approaches are outlined.
5.	Agostini, Marco, 1987, et al. (författare) Designing a Safe Electrolyte Enabling Long‐Life Li/S Batteries 2019 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 12:18, s. 4176-4184 Tidskriftsartikel (refereegranskat)abstract Lithium–sulfur (Li/S) batteries suffer from “shuttle” reactions in which soluble polysulfide species continuously migrate to and from the Li metal anode. As a consequence, the loss of active material and reactions at the surface of Li limit the practical applications of Li/S batteries. LiNO3 has been proposed as an electrolyte additive to reduce the shuttle reactions by aiding the formation of a stable solid electrolyte interphase (SEI) at the Li metal, limiting polysulfide shuttling. However, LiNO3 is continuously consumed during cycling, especially at low current rates. Therefore, the Li/S battery cycle life is limited by the LiNO3 concentration in the electrolyte. In this work, an ionic liquid (IL) [N-methyl-(n-butyl)pyrrolidinium bis(trifluoromethylsulfonyl)imide] was used as an additive to enable longer cycle life of Li/S batteries. By tuning the IL concentration, an enhanced stability of the SEI and lower flammability of the solutions were demonstrated, that is, higher safety of the battery. The Li/S cell built with a high sulfur mass loading (4 mg cm−2) and containing the IL-based electrolyte demonstrated a stable capacity of 600 mAh g−1 for more than double the number of cycles of a cell containing LiNO3 additive.
6.	Agostini, Marco, 1987, et al. (författare) Rational Design of Low Cost and High Energy Lithium Batteries through Tailored Fluorine-free Electrolyte and Nanostructured S/C Composite 2018 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 11:17, s. 2981-2986 Tidskriftsartikel (refereegranskat)abstract We report a new Li–S cell concept based on an optimized F-free catholyte solution and a high loading nanostructured C/S composite cathode. The Li2S8present in the electrolyte ensures both buffering against active material dissolution and Li+conduction. The high S loading is obtained by confining elemental S (≈80 %) in the pores of a highly ordered mesopores carbon (CMK3). With this concept we demonstrate stabilization of a high energy density and excellent cycling performance over 500 cycles. This Li–S cell has a specific capacity that reaches over 1000 mA h g−1, with an overall S loading of 3.6 mg cm−2and low electrolyte volume (i.e., 10 μL cm−2), resulting in a practical energy density of 365 Wh kg−1. The Li–S system proposed thus meets the requirements for large scale energy storage systems and is expected to be environmentally friendly and have lower cost compared with the commercial Li-ion battery thanks to the removal of both Co and F from the overall formulation.
7.	Agostini, Marco, 1987, et al. (författare) Stabilizing the Performance of High-Capacity Sulfur Composite Electrodes by a New Gel Polymer Electrolyte Configuration 2017 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 10:17, s. 3490-3496 Tidskriftsartikel (refereegranskat)abstract Increased pollution and the resulting increase in global warming are drawing attention to boosting the use of renewable energy sources such as solar or wind. However, the production of energy from most renewable sources is intermittent and thus relies on the availability of electrical energy-storage systems with high capacity and at competitive cost. Lithium–sulfur batteries are among the most promising technologies in this respect due to a very high theoretical energy density (1675 mAh g?1) and that the active material, sulfur, is abundant and inexpensive. However, a so far limited practical energy density, life time, and the scaleup of materials and production processes prevent their introduction into commercial applications. In this work, we report on a simple strategy to address these issues by using a new gel polymer electrolyte (GPE) that enables stable performance close to the theoretical capacity of a low cost sulfur–carbon composite with high loading of active material, that is, 70 % sulfur. We show that the GPE prevents sulfur dissolution and reduces migration of polysulfide species to the anode. This functional mechanism of the GPE membranes is revealed by investigating both its morphology and the Li-anode/GPE interface at various states of discharge/charge using Raman spectroscopy.
8.	Ahlgren, Per, 1960-, et al. (författare) BATTERY 2030+ and its Research Roadmap : A Bibliometric Analysis. 2023 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 16:21 Tidskriftsartikel (refereegranskat)abstract In this bibliometric study, we analyze two of the six battery research subfields identified in the BATTERY 2030+ roadmap: Materials Acceleration Platform and Smart functionalities: Sensing. In addition, we analyze the entire research field related to BATTERY 2030+ as a whole. We (a) evaluate the European standing in the two subfields/the BATTERY 2030+ field in comparison to the rest of the world, and (b) identify strongholds of the two subfields/the BATTERY 2030+ field across Europe. For each subfield and the field as a whole, we used seed articles, i. e. articles listed in the BATTERY 2030+ roadmap or cited by such articles, in order to generate additional, similar articles located in an algorithmically obtained classification system. The output of the analysis is publication volumes, field normalized citation impact values with comparisons between country/country aggregates and between organizations, co-publishing networks between countries and organizations, and keyword co-occurrence networks.
9.	Alammar, Tarek, et al. (författare) Ionic-Liquid-Assisted Microwave Synthesis of Solid Solutions of Sr1-xBaxSnO3 Perovskite for Photocatalytic Applications 2017 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 10:17, s. 3387-3401 Tidskriftsartikel (refereegranskat)abstract Nanocrystalline Sr1-xBaxSnO3 (x=0, 0.2, 0.4, 0.8, 1) perovskite photocatalysts were prepared by microwave synthesis in an ionic liquid (IL) and subsequent heat-treatment. The influence of the Sr/Ba substitution on the structure, crystallization, morphology, and photocatalytic efficiency was investigated and the samples were fully characterized. On the basis of X-ray diffraction results, as the Ba content in the SrSnO3 lattice increases, a symmetry increase was observed from the orthorhombic perovskite structure for SrSnO3 to the cubic BaSnO3 structure. The analysis of the sample morphology by SEM reveals that the Sr1-xBaxSnO3 samples favor the formation of nanorods (500nm-5m in diameter and several micrometers long). The photophysical properties were examined by UV/Vis diffuse reflectance spectroscopy. The band gap decreases from 3.85 to 3.19eV with increasing Ba2+ content. Furthermore, the photocatalytic properties were evaluated for the hydroxylation of terephthalic acid (TA). The order of the activities for TA hydroxylation was Sr0.8Ba0.2SnO3>SrSnO3>BaSnO3>Sr0.6Ba0.4SnO3>Sr0.2Ba0.8SnO3. The highest photocatalytic activity was observed for Sr0.8Ba0.2SnO3, and this can be attributed to the synergistic impacts of the modification of the crystal structure and morphology, the relatively large surface area associated with the small crystallite size, and the suitable band gap and band-edge position.
10.	Anugwom, Ikenna, et al. (författare) Switchable ionic liquids as delignification solvents for lignocellulosic materials 2014 Ingår i: ChemSusChem. - : John Wiley & Sons. - 1864-5631 .- 1864-564X. ; 7:4, s. 1170-1176 Tidskriftsartikel (refereegranskat)abstract The transformation of lignocellulosic materials into potentially valuable resources is compromised by their complicated structure. Consequently, new economical and feasible conversion/fractionation techniques that render value-added products are intensely investigated. Herein an unorthodox and feasible fractionation method of birch chips (B. pendula) using a switchable ionic liquid (SIL) derived from an alkanol amine (monoethanol amine, MEA) and an organic super base (1,8-diazabicyclo-[5.4.0]-undec-7-ene, DBU) with two different trigger acid gases (CO2 and SO2 ) is studied. After SIL treatment, the dissolved fractions were selectively separated by a step-wise method using an antisolvent to induce precipitation. The SIL was recycled after concentration and evaporation of anti-solvent. The composition of undissolved wood after MEA-SO2 -SIL treatment resulted in 80 wt % cellulose, 10 wt % hemicelluloses, and 3 wt % lignin, whereas MEA-CO2 -SIL treatment resulted in 66 wt % cellulose, 12 wt % hemicelluloses and 11 wt % lignin. Thus, the MEA-SO2 -SIL proved more efficient than the MEA-CO2 -SIL, and a better solvent for lignin removal. All fractions were analyzed by gas chromatography (GC), Fourier transform infrared spectroscopy (FT-IR), (13) C nuclear magnetic resonance spectroscopy (NMR) and Gel permeation chromatography (GPC).
11.	Argyropoulos, Dimitris D. S., et al. (författare) Kraft Lignin: A Valuable, Sustainable Resource, Opportunities and Challenges 2023 Ingår i: ChemSusChem. - : John Wiley and Sons Inc. - 1864-5631 .- 1864-564X. ; 16:23 Forskningsöversikt (refereegranskat)abstract Kraft lignin, a by-product from the production of pulp, is currently incinerated in the recovery boiler during the chemical recovery cycle, generating valuable bioenergy and recycling inorganic chemicals to the pulping process operation. Removing lignin from the black liquor or its gasification lowers the recovery boiler load enabling increased pulp production. During the past ten years, lignin separation technologies have emerged and the interest of the research community to valorize this underutilized resource has been invigorated. The aim of this Review is to give (1) a dedicated overview of the kraft process with a focus on the lignin, (2) an overview of applications that are being developed, and (3) a techno-economic and life cycle asseeements of value chains from black liquor to different products. Overall, it is anticipated that this effort will inspire further work for developing and using kraft lignin as a commodity raw material for new applications undeniably promoting pivotal global sustainability concerns.
12.	Baggi, Nicolò, et al. (författare) Flow-Integrated Preparation of Norbornadiene Precursors for Solar Thermal Energy Storage 2024 Ingår i: ChemSusChem. - 1864-5631 .- 1864-564X. ; 17:2 Tidskriftsartikel (refereegranskat)abstract Molecular solar thermal (MOST) energy storage systems are getting increased attention related to renewable energy storage applications. Particularly, 2,3-difunctionalized norbornadiene-quadricyclane (NBD-QC) switches bearing a nitrile (CN) group as one of the two substituents are investigated as promising MOST candidates thanks to their high energy storage densities and their red-shifted absorbance. Moreover, such NBD systems can be prepared in large quantities (a requirement for MOST-device applications) in flow through Diels-Alder reaction between cyclopentadiene and appropriately functionalized propynenitriles. However, these acetylene precursors are traditionally prepared in batch from their corresponding acetophenones using reactive chemicals potentially leading to health and physical hazards, especially when working on a several-grams scale. Here, we develop a multistep flow-chemistry route to enhance the production of these crucial precursors. Furthermore, we assess the atom economy (AE) and the E-factor showing improved green metrics compared to classical batch methods. Our results pave the way for a complete flow synthesis of NBDs with a positive impact on green chemistry aspects.
13.	Balakshin, Mikhail Yu, et al. (författare) New Opportunities in the Valorization of Technical Lignins. 2021 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 14:4, s. 1016-1036 Tidskriftsartikel (refereegranskat)abstract Sugar-based biorefineries have faced significant economic challenges. Biorefinery lignins are often classified as low-value products (fuel or low-cost chemical feedstock) mainly due to low lignin purities in the crude material. However, recent research has shown that biorefinery lignins have a great chance of being successfully used as high-value products, which in turn should result in an economy renaissance of the whole biorefinery idea. This critical review summarizes recent developments from our groups, along with the state-of-the-art in the valorization of technical lignins, with the focus on biorefinery lignins. A beneficial synergistic effect of lignin and cellulose mixtures used in different applications (wood adhesives, carbon fiber and nanofibers, thermoplastics) has been demonstrated. This phenomenon causes crude biorefinery lignins, which contain a significant amount of residual crystalline cellulose, to perform superior to high-purity lignins in certain applications. Where previously specific applications required high-purity and/or functionalized lignins with narrow molecular weight distributions, simple green processes for upgrading crude biorefinery lignin are suggested here as an alternative. These approaches can be easily combined with lignin micro-/nanoparticles (LMNP) production. The processes should also be cost-efficient compared to traditional lignin modifications. Biorefinery processes allow much greater flexibility in optimizing the lignin characteristics desirable for specific applications than traditional pulping processes. Such lignin engineering, at the same time, requires an efficient strategy capable of handling large datasets to find correlations between process variables, lignin structures and properties and finally their performance in different applications.
14.	Baltrusaitis, J., et al. (författare) Photoelectrochemical Hydrogen Production on alpha-Fe2O3 (0001): Insights from Theory and Experiments 2014 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 7:1, s. 162-171 Tidskriftsartikel (refereegranskat)abstract The photoelectrochemical (PEC) decomposition of organic compounds in wastewater is investigated by using quantum chemical (DFT) methods to evaluate alternatives to water splitting for the production of renewable and sustainable hydrogen. Methanol is used as a model organic species for the theoretical evaluations of electrolysis on the surface of the widely available semiconductor hematite, alpha-Fe2O3, a widely studied photocatalyst. Three different alpha-Fe2O3 surface terminations were investigated, including the predominant surface found in aqueous electrolytes, (OH)(3)-R. The PEC oxidation of methanol is energetically downhill, producing CO2 and protons. The protons are reduced to hydrogen on the cathode. Experimental PEC measurements were also performed for several polyalcoholic compounds, glycerol, erythritol, and xylitol, on alpha-Fe2O3 as the photocatalyst and showed high incident-photon-to-current-efficiencies (IPCE) that were much greater than those of water splitting. Interestingly, high IPCEs were observed for hydrogen production from polyalcohols in the absence of any applied bias, which was not thought to be possible on hematite. These results support the potential application of PEC for hydrogen production by using widely available hematite for the PEC oxidation of selected components of organic wastewater present in large quantities from anthropogenic and industrial sources.
15.	Beller, M., et al. (författare) Chemistry Future : Priorities and Opportunities from the Sustainability Perspective 2017 Ingår i: ChemSusChem. - : John Wiley & Sons. - 1864-5631 .- 1864-564X. ; 10:1, s. 6-13 Tidskriftsartikel (refereegranskat)abstract To celebrate the 10 year anniversary of ChemSusChem, we as the chairmen of the editorial board are writing this Essay to summarize important scientific contributions to our journal during the past decade in terms of sustainable science and technology. Bibliometric analysis of published papers show that biorefinery, solar energy conversion, energy-storage materials, and carbon dioxide utilizations attracted most attention in this area. According to our own knowledge and understanding and from the sustainability point of view, we are also pointing out those research directions that we believe can play key roles in the future chemistry to meet the grand challenges in energy and environment. Hopefully, these perspective aspects will provide the readers with new angles to look at the chemistry in the coming decades and inspire the development of new technologies to make our society sustainable.
16.	Benselfelt, Tobias, et al. (författare) The Colloidal Properties of Nanocellulose 2023 Ingår i: ChemSusChem. - : John Wiley and Sons Inc. - 1864-5631 .- 1864-564X. ; 16:8, s. e202201955- Tidskriftsartikel (refereegranskat)abstract Nanocelluloses are anisotropic nanoparticles of semicrystalline assemblies of glucan polymers. They have great potential as renewable building blocks in the materials platform of a more sustainable society. As a result, the research on nanocellulose has grown exponentially over the last decades. To fully utilize the properties of nanocelluloses, a fundamental understanding of their colloidal behavior is necessary. As elongated particles with dimensions in a critical nanosize range, their colloidal properties are complex, with several behaviors not covered by classical theories. In this comprehensive Review, we describe the most prominent colloidal behaviors of nanocellulose by combining experimental data and theoretical descriptions. We discuss the preparation and characterization of nanocellulose dispersions, how they form networks at low concentrations, how classical theories cannot describe their behavior, and how they interact with other colloids. We then show examples of how scientists can use this fundamental knowledge to control the assembly of nanocellulose into new materials with exceptional properties. We hope aspiring and established researchers will use this Review as a guide. © 2023 The Authors.
17.	Björnerbäck, Fredrik, et al. (författare) Highly Porous Hypercrosslinked Polymers Derived from Biobased Molecules 2019 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 12:4, s. 839-847 Tidskriftsartikel (refereegranskat)abstract Highly porous and hyper-cross-linked polymers (HCPs) have a range of applications and are typically synthesized in an unsustainable manner. Herein, HCPs were synthesized from abundant biobased or biorelated compounds in sulfolane with iron(III) chloride as Lewis acid catalyst. As reactants, quercetin, tannic acid, phenol, 1,4-dimethoxybenzene, glucose, and a commercial bark extract were used. The HCPs had high CO2 uptake (up to 3.94 mmol g(-1) at 0 degrees C and 1 bar), total pore volumes (up to 1.86 cm(3) g(-1)), and specific surface areas (up to 1440 m(2) g(-1)). H-1 NMR, C-13 NMR, and IR spectroscopy, wide-angle X-ray scattering, elemental analysis, and SEM revealed, for example, that the HCPs consisted of amorphous and cross-linked aromatic and phenolic structures with significant contents of aliphatics, oxygen, and sulfur.
18.	Budarin, Vitaliy L, et al. (författare) Processed Lignin as a Byproduct of the Generation of 5-(Chloromethyl)furfural from Biomass : A Promising New Mesoporous Material. 2015 Ingår i: ChemSusChem. - : John Wiley & Sons. - 1864-5631 .- 1864-564X. ; 8:24, s. 4172-9 Tidskriftsartikel (refereegranskat)abstract The lignin by-product of the conversion of lignocellulosic biomass to 5-(chloromethyl)furfural (CMF) has been characterised by thermogravimetric analysis, N2 physisorption porosimetry, attenuated internal reflectance IR spectroscopy, elemental analysis and solid-state NMR spectroscopy. The lignin (LCMF) has a moderate level of mesoporosity before thermal treatment and a surface area of 63 m(2) g(-1) , which increases dramatically on pyrolysis at temperatures above 400 °C. An assessment of the functionality and textural properties of the material was achieved by analysing LCMF treated thermally over a range of pyrolysis temperatures. Samples were sulfonated to test their potential as heterogeneous acid catalysts in the esterification of levulinic acid. It was shown that unpyrolysed catalysts gave the highest ester yields of up to 93 %. To the best of our knowledge, this is the first example of mesoporous lignin with an appreciable surface area that is produced directly from a bio-refinery process and with further textural modification of the material demonstrated.
19.	Budnyak, Tetyana M., et al. (författare) Lignin-Inorganic Interfaces : Chemistry and Applications from Adsorbents to Catalysts and Energy Storage Materials 2020 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 13:17, s. 4344-4355 Forskningsöversikt (refereegranskat)abstract Lignin is one the most fascinating natural polymers due to its complex aromatic‐aliphatic structure. Phenolic hydroxyl and carboxyl groups along with other functional groups provide technical lignins with reactivity and amphiphilic character. Many different lignins have been used as functional agents to facilitate the synthesis and stabilization of inorganic materials. Herein, the use of lignin in the synthesis and chemistry of inorganic materials in selected applications with relevance to sustainable energy and environmental fields is reviewed. In essence, the combination of lignin and inorganic materials creates an interface between soft and hard materials. In many cases it is either this interface or the external lignin surface that provides functionality to the hybrid and composite materials. This Minireview closes with an overview on future directions for this research field that bridges inorganic and lignin materials for a more sustainable future.
20.	Chang, J. F., et al. (författare) Ni2P Makes Application of the PtRu Catalyst Much Stronger in Direct Methanol Fuel Cells 2015 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 8:19, s. 3340-3346 Tidskriftsartikel (refereegranskat)abstract PtRu is regarded as the best catalyst for direct methanol fuel cells, but the performance decay resulting from the loss of Ru seriously hinders commercial applications. Herein, we demonstrated that the presence of Ni2P largely reduces Ru loss, which thus makes the application of PtRu much stronger in direct methanol fuel cells. Outstanding catalytic activity and stability were observed by cyclic voltammetry. Upon integrating the catalyst material into a practical direct methanol fuel cell, the highest maximum power density was achieved on the PtRu-Ni2P/C catalyst among the reference catalysts at different temperatures. A maximum power density of 69.9mWcm-2 at 30°C was obtained on PtRu-Ni2P/C, which is even higher than the power density of the state-of-the-art commercial PtRu catalyst at 70°C (63.1mWcm-2). Moreover, decay in the performance resulting from Ru loss was greatly reduced owing to the presence of Ni2P, which is indicative of very promising applications.
21.	Chen, C., et al. (författare) Boosting Electrocatalytic Water Oxidation by Creating Defects and Lattice-Oxygen Active Sites on Ni-Fe Nanosheets 2020 Ingår i: ChemSusChem. - : Wiley-VCH Verlag. - 1864-5631 .- 1864-564X. ; 13:18, s. 5067-5072 Tidskriftsartikel (refereegranskat)abstract Layered nickel-iron oxide/hydroxide nanosheets have proven to be the most efficient catalyst for the water oxidation reaction. Introducing structural defects to the nanosheets is a particularly attractive method for increasing the number of active sites and tailoring the intrinsic electronic properties. Herein, defects were introduced on Ni−Fe nanosheets through sequentially electrodoping and dedoping the surface of the material with tetramethylammonium ions. The as-prepared defect-rich Ni−Fe nanosheets showed an enhanced catalytic performance for the oxygen evolution reaction (OER) compared with conventional NiFe layered double hydroxides (LDHs), exhibiting an overpotential of only 172 mV at the current density of 10 mA cm−2. The relationship between pH and OER activity indicated that the lattice oxygens participated in the catalytic OER process as active sites. This work provides new insights into the understanding of the structure-activity relationship of layered materials and helps to develop new methods to implement defects on such frameworks aided by organic molecules.
22.	Chen, Cheng, et al. (författare) Degradation of Cyanoacrylic Acid-Based Organic Sensitizers in Dye-Sensitized Solar Cells 2013 Ingår i: ChemSusChem. - : Wiley-VCH Verlagsgesellschaft. - 1864-5631 .- 1864-564X. ; 6:7, s. 1270-1275 Tidskriftsartikel (refereegranskat)abstract Organic dyes have become widely used in dye-sensitized solar cells (DSSCs) because of their good performance, flexible structural modifications, and low costs. To increase the photostability of organic dye-based DSSCs, we conducted a full study on the degradation mechanism of cyanoacrylic acid-based organic sensitizers in DSSCs. The results showed that with the synergy between water and UV light, the sensitizer could desorb from the TiO2 surface and the cyanoacrylic acid unit of the sensitizer was transformed into the aldehyde group. It was also observed that the water content had a great effect on the degradation process. Our experiments conducted using O-18-labeled water demonstrated that the oxygen atom of the aldehyde group identified in the degraded dye came from the solvent water in the DSSCs. Therefore, controlling the water content during DSSC fabrication, good sealing of cells, and filtering the UV light are crucial to produce DSSCs that are more durable and robust.
23.	Chen, Hu, et al. (författare) Highly Active Three-Dimensional NiFe/Cu2O Nanowires/Cu Foam Electrode for Water Oxidation 2017 Ingår i: ChemSusChem. - : Wiley-VCH Verlagsgesellschaft. - 1864-5631 .- 1864-564X. ; 10:7, s. 1475-1481 Tidskriftsartikel (refereegranskat)abstract Water splitting is of paramount importance for exploiting renewable energy-conversion and -storage systems, but is greatly hindered by the kinetically sluggish oxygen evolution reaction (OER). In this work, a three-dimensional, highly efficient, and durable NiFe/Cu2O nanowires/Cu foam anode (NiFe/Cu2O NWs/CF) for water oxidation in 1.0m KOH was developed. The obtained electrode exhibited a current density of 10mAcm(-2) at a uniquely low overpotential of =215mV. The average specific current density (j(s)) was estimated, on the basis of the electrocatalytically active surface area, to be 0.163mAcm(-2) at =310mV. The electrode also displayed a low Tafel slope of 42mVdecade(-1). Moreover, the NiFe/Cu2O NWs/CF electrode could maintain a steady current density of 100mAcm(-2) for 50h at an overpotential of =260mV. The outstanding electrochemical performance of the electrode for the OER was attributed to the high conductivity of the Cu foam and the specific structure of the electrode with a large interfacial area.
24.	Cheng, Ming, et al. (författare) Efficient Organic Dye-Sensitized Solar Cells : Molecular Engineering of Donor-Acceptor-Acceptor cationic dyes 2013 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 6:12, s. 2322-2329 Tidskriftsartikel (refereegranskat)abstract Three metal-free donor-acceptor-acceptor sensitizers with ionized pyridine and a reference dye were synthesized, and a detailed investigation of the relationship between the dye structure and the photophysical and photoelectrochemical properties and the performance of dye-sensitized solar cells (DSSCs) is described. The ionization of pyridine results in a red shift of the absorption spectrum in comparison to that of the reference dye. This is mainly attributable to the ionization of pyridine increasing the electron-withdrawing ability of the total acceptor part. Incorporation of the strong electron-withdrawing units of pyridinium and cyano acrylic acid gives rise to optimized energy levels, resulting in a large response range of wavelengths. When attached to TiO2 film, the conduction band of TiO2 is negatively shifted to a different extent depending on the dye. This is attributed to the electron recombination rate between the TiO2 film and the electrolyte being efficiently suppressed by the introduction of long alkyl chains and thiophene units. DSSCs assembled using these dyes show efficiencies as high as 8.8%.
25.	Cong, Jiayan, et al. (författare) Electrolytes Based on TEMPO-Co Tandem Redox Systems Outperform Single Redox Systems in Dye-sensitized Solar Cells 2015 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 8:2, s. 264-268 Tidskriftsartikel (refereegranskat)abstract A new TEMPO-Co tandem redox system with TEMPO and Co(bpy)(3)(2+/3+) has been investigated for the use in dye-sensitized solar cells (DSSCs). A large open-circuit voltage (V-OC) increase, from 862 mV to 965 mV, was observed in the tandem redox system, while the short-circuit current density (J(SC)) was maintained. The conversion efficiency was observed to increase from 7.1% for cells containing the single Co(bpy)(3)(2+/3+) redox couple, to 8.4% for cells containing the TEMPO-Co tandem redox system. The reason for the increase in V-OC and overall efficiency is ascribed to the involvement of partial regeneration of the sensitizing dye molecules by TEMPO. This assumption can be verified through the observed much faster regeneration dynamics exhibited in the presence of the tandem system. Using the tandem redox system, the faster recombination problem of the single TEMPO redox couple is resolved and the mass-transport of the metal-complex-based electrolyte is also improved. This TEMPO-Co tandem system is so far the most effienct tandem redox electrolyte reported not involving iodine. The current results show a promising future for tandem system as replacements for single redox systems in electrolytes for DSSCs.
26.	Das, Biswanath, et al. (författare) Iron Pentapyridyl Complexes as Molecular WaterOxidation Catalysts : Strong Influence of a Chloride Ligandand pH in Altering the Mechanism 2016 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 9:10, s. 1178-1186 Tidskriftsartikel (refereegranskat)abstract The development of molecular water oxidation catalysts basedon earth-abundant, non-noble metals is essential for artificial photosynthesis research. Iron, which is the most abundant transition metal in the earth's crust, is a prospective candidate for this purpose. Herein, we report two iron complexes based on the polypyridyl ligand Py5OH (Py5OH=pyridine-2,6-diylbis[di(pyridin-2-yl)methanol]) that can catalyse water oxidation to produce O2 in RuIII-induced (at pH 8, highest turnover number (TON)=26.5; turnover frequency (TOF)=2.2 s-1), CeIV-induced(at pH 1.5 highest TON=16; TOF=0.75 s-1) and photo-induced(at pH 8, highest TON=43.5; TOF=0.6 s-1) reactions. A chloride ligand in one of the iron complexes is shown to affect the activity strongly, improve stability and, thereby, the performance at pH 8 but it inhibits oxygen evolution at pH 1.5. The observations are consistent with a change in mechanism for catalytic water oxidation with the Fe(Py5OH) complexes between acidic (CeIV) and near-neutral pH (RuIII).
27.	Dau, H., et al. (författare) Artificial Photosynthesis : Beyond Mimicking Nature 2017 Ingår i: ChemSusChem. - : Wiley-VCH Verlagsgesellschaft. - 1864-5631 .- 1864-564X. ; 10:22, s. 4228-4235 Tidskriftsartikel (refereegranskat)abstract In this Editorial, Guest Editors Holger Dau, Etsuko Fujita, and Licheng Sun introduce the Special Issue of ChemSusChem on “Artificial Photosynthesis for Sustainable Fuels”. They discuss the need for non-fossil based fuels, introduce both biological and artificial photosynthesis, and outline various important concepts in artificial photosynthesis, including molecular and solid-state catalysts for water oxidation and hydrogen evolution, catalytic CO2 reduction, and photoelectrochemical systems.
28.	De Santi, Alessandra, et al. (författare) Lignin‐First Fractionation of Softwood Lignocellulose Using a Mild Dimethyl Carbonate and Ethylene Glycol Organosolv Process 2020 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 13:17, s. 4468-4477 Tidskriftsartikel (refereegranskat)abstract A mild lignin-first acidolysis process (140 °C, 40 min) was developed using the benign solvent dimethyl carbonate (DMC) and ethylene glycol (EG) as a stabilization agent/solvent to produce a high yield of aromatic monophenols directly from softwood lignocellulose (pine, spruce, cedar, and Douglas fir) with a depolymerization efficiency of 77–98 %. Under the optimized conditions (140 °C, 40 min, 400 wt % EG and 2 wt % H2SO4 to pinewood), up to 9 wt % of the aromatic monophenol was produced, reaching a degree of delignification in pinewood of 77 %. Cellulose was also preserved, as evidenced by a 85 % glucose yield after enzymatic digestion. An in-depth analysis of the depolymerization oil was conducted by using GC-MS, HPLC, 2 D-NMR, and size-exclusion chromatography, which provided structural insights into lignin-derived dimers and oligomers and the composition of the sugars and derived molecules. Mass balance evaluation was performed.
29.	Di Francesco, Davide, 1989-, et al. (författare) A New Family of Renewable Thermosets : Kraft Lignin Poly-adipates 2022 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 15:11 Tidskriftsartikel (refereegranskat)abstract Thermosetting polymeric materials have advantageous properties and are therefore used in numerous applications. In this study, it was hypothesized and ultimately shown that thermosets could be derived from comparably sustainable sub-components. A two-step procedure to produce a thermoset comprising of Kraft lignin (KL) and the cross-linker adipic acid (AdA) was developed. The cross-linking was activated by means of an acetylating agent comprising isopropenyl acetate (IPA) to form a cross-linking mixture (CLM). The cross-linking was confirmed by FTIR and solid-state NMR spectroscopy, and the esterification reactions were further studied using model compounds. When the KL lignin was mixed with the CLM, partial esterification occurred to yield a homogeneous viscous liquid that could easily be poured into a mold, as the first step in the procedure. Without any additions, the mold was heated and the material transformed into a thermoset by reaction of the two carboxylic acid-derivatives of AdA and KL in the second step.
30.	Di Francesco, Davide, et al. (författare) Debottlenecking a Pulp Mill by Producing Biofuels from Black Liquor in Three Steps 2021 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 14:11, s. 2414-2425 Tidskriftsartikel (refereegranskat)abstract By extracting lignin, pulp production can be increased without heavy investments in a new recovery boiler, the typical bottleneck of a pulp mill. The extraction is performed by using 0.20 and 0.15 weight equivalents of CO2 and H2SO4 respectively. Herein, we describe lignin esterification with fatty acids using benign reagents to generate a lignin ester mixable with gas oils. The esterification is accomplished by activating the fatty acid and lignin with acetic anhydride which can be regenerated from the acetic acid recycled in this reaction. The resulting mass balance ratio is fatty acid/lignin/acetic acid (2 : 1 : 0.1). This lignin ester can be hydroprocessed to generate hydrocarbons in gasoline, aviation, and diesel range. A 300-hour continuous production of fuel was accomplished. By recirculating reagents from both the esterification step and applying a water gas shift reaction on off-gases from the hydroprocessing, a favorable overall mass balance is realized.
31.	Ding, Xin, et al. (författare) Assembling Supramolecular Dye-Sensitized Photoelectrochemical Cells for Water Splitting 2015 Ingår i: ChemSusChem. - : Wiley-VCH Verlagsgesellschaft. - 1864-5631 .- 1864-564X. ; 8:23, s. 3992-3995 Tidskriftsartikel (refereegranskat)abstract The method used to assemble dye-sensitized photoelectrochemical (DS-PEC) devices plays a vital role in determining its photoactivity and stability. We report a simple and effective method to assemble supramolecular DS-PECs introducing PMMA as support material and a catalyst modified with long carbon chains as photoanodes. The long carbon chains in combination with PMMA allow to better immobilize the catalyst. DS-PECs obtained by this simple method have display excellent photoactivities and stabilities. A photocurrent density of 1.1mAcm(-2) and a maximum IPCE of 9.5% have been obtained with a 0.2V vs NHE external bias.
32.	Doubaji, Siham, et al. (författare) Passivation Layer and Cathodic Redox Reactions in Sodium-Ion Batteries Probed by HAXPES 2016 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 9:1, s. 97-108 Tidskriftsartikel (refereegranskat)abstract The cathode material P2-NaxCo2/3Mn2/9Ni1/9O2, which could be used in Na-ion batteries, was investigated through synchrotron-based hard X-ray photoelectron spectroscopy (HAXPES). Nondestructive analysis was made through the electrode/electrolyte interface of the first electrochemical cycle to ensure access to information not only on the active material, but also on the passivation layer formed at the electrode surface and referred to as the solid permeable interface (SPI). This investigation clearly shows the role of the SPI and the complexity of the redox reactions. Cobalt, nickel, and manganese are all electrochemically active upon cycling between 4.5 and 2.0V; all are in the 4+ state at the end of charging. Reduction to Co3+, Ni3+, and Mn3+ occurs upon discharging and, at low potential, there is partial reversible reduction to Co2+ and Ni2+. A thin layer of Na2CO3 and NaF covers the pristine electrode and reversible dissolution/reformation of these compounds is observed during the first cycle. The salt degradation products in the SPI show a dependence on potential. Phosphates mainly form at the end of the charging cycle (4.5V), whereas fluorophosphates are produced at the end of discharging (2.0V).
33.	Etman, Ahmed S., et al. (författare) Flexible Freestanding MoO3-x-Carbon Nanotubes-Nanocellulose Paper Electrodes for Charge-Storage Applications 2019 Ingår i: ChemSusChem. - : John Wiley & Sons. - 1864-5631 .- 1864-564X. ; 12:23, s. 5157-5163 Tidskriftsartikel (refereegranskat)abstract Herein, a one‐step synthesis protocol was developed for synthesizing freestanding/flexible paper electrodes composed of nanostructured molybdenum oxide (MoO3−x) embedded in a carbon nanotube (CNT) and Cladophora cellulose (CC) matrix. The preparation method involved sonication of the precursors, nanostructured MoO3−x, CNTs, and CC with weight ratios of 7:2:1, in a water/ethanol mixture, followed by vacuum filtration. The electrodes were straightforward to handle and possessed a thickness of approximately 12 μm and a mass loading of MoO3−x–CNTs of approximately 0.9 mg cm−2. The elemental mapping showed that the nanostructured MoO3−x was uniformly embedded inside the CNTs–CC matrix. The MoO3−x–CNTs–CC paper electrodes featured a capacity of 30 C g−1, normalized to the mass of MoO3−x–CNTs, at a current density of 78 A g−1 (corresponding to a rate of approximately 210 C based on the MoO3 content, assuming a theoretical capacity of 1339 C g−1), and exhibited a capacity retention of 91 % over 30 000 cycles. This study paves the way for the manufacturing of flexible/freestanding nanostructured MoO3−x‐based electrodes for use in charge‐storage devices at high charge/discharge rates.
34.	Fan, Ke, et al. (författare) Immobilization of a Molecular Ruthenium Catalyst on Hematite Nanorod Arrays for Water Oxidation with Stable Photocurrent 2015 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 8:19, s. 3242-3247 Tidskriftsartikel (refereegranskat)abstract Photoelectrochemical (PEC) cells for light-driven water splitting are prepared using hematite nanorod arrays on conductive glass as the photoanode. These devices improve the photocurrent of the hematite-based photoanode for water splitting, owing to fewer surface traps and decreased electron recombination resulting from the one-dimensional structure. By employing a molecular ruthenium co-catalyst, which contains a strong 2,6-pyridine-dicarboxylic acid anchoring group at the hematite photoanode, the photocurrent of the PEC cell is enhanced with high stability for over 10000s in a 1M KOH solution. This approach can pave a route for combining one-dimensional nanomaterials and molecular catalysts to split water with high efficiency and stability.
35.	Fan, Lizhou, et al. (författare) Molecular Functionalization of NiO Nanocatalyst for Enhanced Water Oxidation by Electronic Structure Engineering 2020 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 13:22, s. 5901-5909 Tidskriftsartikel (refereegranskat)abstract Tuning the local environment of nanomaterial-based catalysts has emerged as an effective approach to optimize their oxygen evolution reaction (OER) performance, yet the controlled electronic modulation around surface active sites remains a great challenge. Herein, directed electronic modulation of NiO nanoparticles was achieved by simple surface molecular modification with small organic molecules. By adjusting the electronic properties of modifying molecules, the local electronic structure was rationally tailored and a close electronic structure-activity relationship was discovered: the increasing electron-withdrawing modification readily decreased the electron density around surface Ni sites, accelerating the reaction kinetics and improving OER activity, and vice versa. Detailed investigation by operando Raman spectroelectrochemistry revealed that the electron-withdrawing modification facilitates the charge-transfer kinetics, stimulates the catalyst reconstruction, and promotes abundant high-valent gamma-NiOOH reactive species generation. The NiO-C(6)F(5)catalyst, with the optimized electronic environment, exhibited superior performance towards water oxidation. This work provides a well-designed and effective approach for heterogeneous catalyst fabrication under the molecular level.
36.	Farré, Yoann, et al. (författare) A Comparative Investigation of the Role of the Anchoring Group on Perylene Monoimide Dyes in NiO-Based Dye-Sensitized Solar Cells 2020 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 13:7, s. 1844-1855 Tidskriftsartikel (refereegranskat)abstract The anchoring group of a sensitizer may strongly affect the overall properties and stability of the resulting dye-sensitized solar cells (DSSCs) and dye-sensitized photoelectrosynthetic solar cells (DSPECs). The properties of seven perylene monoimide (PMI) dyes have been comprehensively studied for their immobilization on nanocrystalline NiO film. The PMI dyes differ only by the nature of the anchoring group, which are: carboxylic acid (PMI-CO2H), phosphonic acid (PMI-PO3H2), acetyl acetone (PMI-acac), pyridine (PMI-Py), aniline (PMI-NH2), hydroxyquinoline (PMI-HQ), and dipicolinic acid (PMI-DPA). The dyes are investigated by cyclic voltammetry and spectroelectrochemistry and modeled by TD-DFT quantum chemical calculations. The mode of binding of these anchoring groups is investigated by infrared spectroscopy and the stability of the binding to NiO surface is studied by desorption experiments in acidic and basic media. The phosphonic acid group is found to offer the strongest binding to the NiO surface in terms of stability and dye loading. Finally, a photophysical study by ultrafast transient absorption spectroscopy shows that all dyes inject a hole in NiO with rate constants on a subpicosecond timescale and display similar charge recombination kinetics. The photovoltaic properties of the dyes show that PMI-HQ and PMI-acac give the highest photovoltaic performances, owing to a lower degree of aggregation on the surface.
37.	Ferdowsi, Parnian, et al. (författare) Molecular Design of Efficient Organic D-A-pi-A Dye Featuring Triphenylamine as Donor Fragment for Application in Dye-Sensitized Solar Cells 2018 Ingår i: ChemSusChem. - : WILEY-V C H VERLAG GMBH. - 1864-5631 .- 1864-564X. ; 11:2, s. 494-502 Tidskriftsartikel (refereegranskat)abstract A metal-free organic sensitizer, suitable for the application in dye-sensitized solar cells (DSSCs), has been designed, synthesized and characterized both experimentally and theoretically. The structure of the novel donor-acceptor--bridge-acceptor (D-A-pi-A) dye incorporates a triphenylamine (TPA) segment and 4-(benzo[c][1,2,5]thiadiazol-4-ylethynyl)benzoic acid (BTEBA). The triphenylamine unit is widely used as an electron donor for photosensitizers, owing to its nonplanar molecular configuration and excellent electron-donating capability, whereas 4-(benzo[c][1,2,5]thiadiazol-4-ylethynyl)benzoic acid is used as an electron acceptor unit. The influences of I-3(-)/I-, [Co(bpy)(3)](3+/2+) and [Cu(tmby)(2)](2+/+) (tmby=4,4,6,6-tetramethyl-2,2-bipyridine) as redox electrolytes on the DSSC device performance were also investigated. The maximal monochromatic incident photon-to-current conversion efficiency (IPCE) reached 81% and the solar light to electrical energy conversion efficiency of devices with [Cu(tmby)(2)](2+/+) reached 7.15%. The devices with [Co(bpy)(3)](3+/2+) and I-3(-)/I- electrolytes gave efficiencies of 5.22% and 6.14%, respectively. The lowest device performance with a [Co(bpy)(3)](3+/2+)-based electrolyte is attributed to increased charge recombination.
38.	Ferdowsi, Parnian, et al. (författare) Molecular Engineering of Simple Metal-Free Organic Dyes Derived from Triphenylamine for Dye-Sensitized Solar Cell Applications 2020 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 13:1, s. 212-220 Tidskriftsartikel (refereegranskat)abstract Two new metal-free organic sensitizers, L156 and L224, were designed, synthesized, and characterized for application in dye-sensitized solar cells (DSCs). The structures of the dyes contain a triphenylamine (TPA) segment and 4-(benzo[c][1,2,5]thiadiazol-4-yl)benzoic acid as electron-rich and -deficient moieties, respectively. Two different pi bridges, thiophene and 4,8-bis(4-hexylphenyl)benzo[1,2-b:4,5-b ']dithiophene, were used for L156 and L224, respectively. The influence of iodide/triiodide, [Co(bpy)(3)](2+/3+) (bpy=2,2 '-bipyridine), and [Cu(tmby)(2)](2+/+) (tmby=4,4 ',6,6 '-tetramethyl-2,2 '-bipyridine) complexes as redox electrolytes and 18 NR-T and 30 NR-D transparent TiO2 films on the DSC device performance was investigated. The L156-based DSC with [Cu(tmby)(2)](2+/+) complexes as the redox electrolyte resulted in the best performance of 9.26 % and a remarkably high open-circuit voltage value of 1.1 V (1.096 V), with a short-circuit current of 12.2 mA cm(-2) and a fill factor of 0.692, by using 30 NR-D TiO2 films. An efficiency of up to 21.9 % was achieved under a 1000 lx indoor light source, which proved that dye L156 was also an excellent candidate for indoor applications. The maximal monochromatic incident-photon-to-current conversion efficiency of L156-30 NR-D reached up to 70 %.
39.	Galkin, Maxim, et al. (författare) Selective Route to 2-Propenyl Aryls Directly from Wood by a Tandem Organosolv and Palladium-Catalysed Transfer Hydrogenolysis 2014 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 7:8, s. 2154-2158 Tidskriftsartikel (refereegranskat)abstract A tandem organosolv pulping and Pd-catalysed transfer hydrogenolysis depolymerisation and deoxygenation has been developed. The tandem process generated 2-methoxy-4-(prop-1-enyl)phenol in 23 % yield (92 % theoretical monomer yield) starting from pine wood and 2,6-dimethoxy-4-(prop-1-enyl)phenol in 49 % yield (92 % theoretical monomer yield) starting from birch wood. Only endogenous hydrogen from wood was consumed, and the reaction was performed using green solvents.
40.	Galkin, Maxim V., et al. (författare) Hydrogen-free catalytic fractionation of woody biomass 2016 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 9:23, s. 3280-3287 Tidskriftsartikel (refereegranskat)abstract The pulping industry could become a biorefinery if the lignin and hemicellulose components of the lignocellulose are valorized. Conversion of lignin into well-defined aromatic chemicals is still a major challenge. Lignin depolymerization reactions often occur in parallel with irreversible condensation reactions of the formed fragments. Here, we describe a strategy that markedly suppresses the undesired condensation pathways and allows to selectively transform lignin into a few aromatic compounds. Notably, applying this strategy to woody biomass at organosolv pulping conditions, the hemicellulose, cellulose, and lignin were separated and in parallel the lignin was transformed into aromatic monomers. In addition, we were able to utilize a part of the lignocellulose as an internal source of hydrogen for the reductive lignin transformations. We hope that the presented methodology will inspire researchers in the field of lignin valorization as well as pulp producers to develop more efficient biomass fractionation processes in the future.
41.	Galkin, Maxim V., et al. (författare) Lignin Valorization through Catalytic Lignocellulose Fractionation : A Fundamental Platform for the Future Biorefinery 2016 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 9:13, s. 1544-1558 Forskningsöversikt (refereegranskat)abstract Current processes for the fractionation of lignocellulosic biomass focus on the production of high-quality cellulosic fibers for paper, board, and viscose production. The other fractions that constitute a major part of lignocellulose are treated as waste or used for energy production. The transformation of lignocellulose beyond paper pulp to a commodity (e.g., fine chemicals, polymer precursors, and fuels) is the only feasible alternative to current refining of fossil fuels as a carbon feedstock. Inspired by this challenge, scientists and engineers have developed a plethora of methods for the valorization of biomass. However, most studies have focused on using one single purified component from lignocellulose that is not currently generated by the existing biomass fractionation processes. A lot of effort has been made to develop efficient methods for lignin depolymerization. The step to take this fundamental research to industrial applications is still a major challenge. This review covers an alternative approach, in which the lignin valorization is performed in concert with the pulping process. This enables the fractionation of all components of the lignocellulosic biomass into valorizable streams. Lignocellulose fractions obtained this way (e.g., lignin oil and glucose) can be utilized in a number of existing procedures. The review covers historic, current, and future perspectives, with respect to catalytic lignocellulose fractionation processes.
42.	Galkin, Maxim V., et al. (författare) Mild and Robust Redox-Neutral Pd/C-Catalyzed Lignol -O-4 Bond Cleavage Through a Low-Energy-Barrier Pathway 2015 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 8:13, s. 2187-2192 Tidskriftsartikel (refereegranskat)abstract A Pd/C catalyzed redox neutral CO bond cleavage of 2-aryloxy-1-arylethanols has been developed. The reactions are carried out at 80 degrees C, in air, using a green solvent system to yield the aryl ketones in near quantitative yields. Addition of catalytic amounts of a hydrogen source to the reaction mixture activates the catalyst to proceed through a low energy barrier pathway. Initial studies support a transfer hydrogenolysis reaction mechanism that proceeds through an initial dehydrogenation followed by an enol adsorption to Pd/C and a reductive CO bond cleavage.
43.	Guo, Boyang, et al. (författare) Fast Depolymerization of PET Bottle Mediated by Microwave Pre-Treatment and An Engineered PETase 2023 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 16:18 Tidskriftsartikel (refereegranskat)abstract Recycling plastics is the key to reaching a sustainable materials economy. Biocatalytic degradation of plastics shows great promise by allowing selective depolymerization of man-made materials into constituent building blocks under mild aqueous conditions. However, insoluble plastics have polymer chains that can reside in different conformations and show compact secondary structures that offer low accessibility for initiating the depolymerization reaction by enzymes. In this work, we overcome these shortcomings by microwave irradiation as a pre-treatment process to deliver powders of polyethylene terephthalate (PET) particles suitable for subsequent biotechnology-assisted plastic degradation by previously generated engineered enzymes. An optimized microwave step resulted in 1400 times higher integral of released terephthalic acid (TPA) from high-performance liquid chromatography (HPLC), compared to original untreated PET bottle. Biocatalytic plastic hydrolysis of substrates originating from PET bottles responded to 78 % yield conversion from 2 h microwave pretreatment and 1 h enzymatic reaction at 30 °C. The increase in activity stems from enhanced substrate accessibility from the microwave step, followed by the administration of designer enzymes capable of accommodating oligomers and shorter chains released in a productive conformation.
44.	Hamidi, Hassan, et al. (författare) Photocurrent Generation from Thylakoid Membranes on Osmium-Redox-Polymer-Modified Electrodes. 2015 Ingår i: ChemSusChem. - : Wiley. - 1864-564X .- 1864-5631. ; 8:6, s. 990-993 Tidskriftsartikel (refereegranskat)abstract Thylakoid membranes (TMs) are uniquely suited for photosynthesis owing to their distinctive structure and composition. Substantial efforts have been directed towards use of isolated photosynthetic reaction centers (PRCs) for solar energy harvesting, however, few studies investigate the communication between whole TMs and electrode surfaces, due to their complex structure. Here we report on a promising approach to generate photosynthesis-derived bioelectricity upon illumination of TMs wired with an osmium-redox-polymer modified graphite electrode, and generate a photocurrent density of 42.4 μA cm(-2) .
45.	Hao, Wenming, et al. (författare) Iron Oxide Nanoparticles Embedded in Activated Carbons Prepared from Hydrothermally Treated Waste Biomass 2014 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 7:3, s. 875-882 Tidskriftsartikel (refereegranskat)abstract Particles of iron oxide (Fe3O4; 20-40nm) were embedded within activated carbons during the activation of hydrothermally carbonized (HTC) biomasses in a flow of CO2. Four different HTC biomass samples (horse manure, grass cuttings, beer production waste, and biosludge) were used as precursors for the activated carbons. Nanoparticles of iron oxide formed from iron catalyst included in the HTC biomasses. After systematic optimization, the activated carbons had specific surface areas of about 800m(2)g(-1). The pore size distributions of the activated carbons depended strongly on the degree of carbonization of the precursors. Activated carbons prepared from highly carbonized precursors had mainly micropores, whereas those prepared from less carbonized precursors contained mainly mesopores. Given the strong magnetism of the activated carbon-nano-Fe3O4 composites, they could be particularly useful for water purification.
46.	Hao, Yan, et al. (författare) Molecular Design to Improve the Performance of Donor-p Acceptor Near-IR Organic Dye-Sensitized Solar Cells 2011 Ingår i: ChemSusChem. - : Wiley-Blackwell. - 1864-5631 .- 1864-564X. ; 4:11, s. 1601-1605 Tidskriftsartikel (refereegranskat)abstract Near-dye experience: Long, flexible carbon chains in the lateral anchoring groups of the donor part of a donor-π acceptor organic dye increase the power conversion efficiency dramatically. This performance enhancement can be ascribed to the prevention of the formation of molecular aggregates on the semiconductor nanoparticles, resulting in a lower recombination rate between transported electrons and I3- ions. A cell based on the new dye, HY113, gives a maximum IPCE value of 93% at 660nm.
47.	Haridas, Anupriya K., et al. (författare) An Electrospun Core–Shell Nanofiber Web as a High-Performance Cathode for Iron Disulfide-Based Rechargeable Lithium Batteries 2018 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 11:20, s. 3625-3630 Tidskriftsartikel (refereegranskat)abstract FeS2/C core–shell nanofiber webs were synthesized for the first time by a unique synthesis strategy that couples electrospinning and carbon coating of the nanofibers with sucrose. The design of the one-dimensional core–shell morphology was found to be greatly beneficial for accommodating the volume changes encountered during cycling, to induce shorter lithium ion diffusion pathways in the electrode, and to prevent sulfur dissolution during cycling. A high discharge capacity of 545 mAh g−1 was retained after 500 cycles at 1 C, exhibiting excellent stable cycling performance with 98.8 % capacity retention at the last cycle. High specific capacities of 854 mAh g−1, 518 mAh g−1, and 208 mAh g−1 were obtained at 0.1 C, 1 C, and 10 C rates, respectively, demonstrating the exceptional rate capability of this nanofiber web cathode.
48.	Harillo-Baños, Albert, et al. (författare) High-Throughput Screening of Blade-Coated Polymer:Polymer Solar Cells: Solvent Determines Achievable Performance 2022 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 15:4 Tidskriftsartikel (refereegranskat)abstract Optimization of a new system for organic solar cells is a multiparametric analysis problem that requires substantial efforts in terms of time and resources. The strong microstructure-dependent performance of polymer:polymer cells makes them particularly difficult to optimize, or to translate previous knowledge from spin coating into more scalable techniques. In this work, the photovoltaic performance of blade-coated devices was studied based on the promising polymer:polymer system PBDB-T and PF5-Y5 as donor and acceptor, respectively. Using the recently developed high-throughput methodology, the system was optimized for multiple variables, including solvent system, active layer composition, ratio, and thickness, among others, by fabricating more than 500 devices with less than 24 mg of each component. As a result, the power conversion efficiency of the blade-coated devices varied from 0.08 to 6.43 % in the best device. The performed statistical analysis of the large experimental data obtained showed that solvent selection had the major impact on the final device performance due to its influence on the active layer microstructure. As a conclusion, the use of the plot of the device efficiency in the Hansen space was proposed as a powerful tool to guide solvent selection in organic photovoltaics.
49.	Hedman, Jonas, et al. (författare) Fibre Optic Sensor for Characterisation of Lithium-Ion Batteries 2020 Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 13:21, s. 5731-5739 Tidskriftsartikel (refereegranskat)abstract The interaction between a fibre optic evanescent wave sensor and the positive electrode material, lithium iron phosphate, in a battery cell is presented. The optical-electrochemical combination was investigated in a reflection-based and a transmission-based configuration, both leading to comparable results. Both constant current cycling and cyclic voltammetry were employed to link the optical response to the charge and discharge of the battery cells, and the results demonstrated that the optical signal changed consistently with lithium ion insertion and extraction. More precisely, cyclic voltammetry showed that the intensity increased when iron was oxidised during charge and then decreased as iron was reduced during discharge. Cyclic voltammetry also revealed that the optical signal remained unchanged when essentially no oxidation or reduction of the electrode material took place. This shows that optical fibre sensors may be used as a way of monitoring state of charge and electrode properties under dynamic conditions.
50.	Huang, Jin, et al. (författare) Update and Challenges in Carbon Dioxide-Based Polycarbonate Synthesis 2020 Ingår i: ChemSusChem. - : Wiley-VCH Verlagsgesellschaft. - 1864-5631 .- 1864-564X. ; 13:3, s. 469-487 Tidskriftsartikel (refereegranskat)abstract The utilization of carbon dioxide as a comonomer to produce polycarbonates has attracted a great deal of attention from both industrial and academic communities because it promises to replace petroleum-derived plastics and supports a sustainable environment. Significant progress in the copolymerization of cyclic ethers (e.g., epoxide, oxetane) and carbon dioxide has been made in recent decades, owing to the rapid development of catalysts. In this Review, the focus is to summarize and discuss recent advances in the development of homogeneous catalysts, including metal- and organo-based complexes, as well as the preparation of carbon dioxide-based block copolymer and functional polycarbonates.

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