| 1. |
- Abdelaziz, Omar, et al.
(författare)
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A Rapid and Tunable Approach for the Fractionation of Technical Kraft Lignin
- 2023
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Ingår i: Chemical Engineering Transactions. - : Italian Association of Chemical Engineering - AIDIC. - 1974-9791 .- 2283-9216. ; 99, s. 67-72
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Tidskriftsartikel (refereegranskat)abstract
- Reducing the heterogeneity of technical lignin is essential to obtain predictable and high-performance polymeric materials that are suitable for high-value applications. Organic solvents with different polarities and solubilities can be used to fractionate lignin and reduce the complexity and diversity of its chemical structure. Among the various solvents and solvent mixtures, acetone-water mixtures offer an energy-efficient, cost-effective, and environmentally friendly means of lignin fractionation. In the present study, temperature-induced acetone-water fractionation was investigated to refine the properties of a technical softwood Kraft lignin, i.e., LignoBoost™ lignin. Relatively mild operating conditions were tested, namely, temperatures of 70-110°C and autogenous pressure. A factorial experimental design was developed using the Design-Expert® software, and three factors (temperature, time, and acetone concentration) were investigated. It was found that temperature-induced fractionation could increase lignin homogeneity and maintain high lignin solubilization with a short processing time (<1 h). It was also possible to tune the properties of the soluble lignin fraction (yield and weight-average molecular weight) based on the factorial models developed. The techno-economic evaluation confirmed the commercial viability of this fractionation process.
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| 2. |
- Baker, Darren, et al.
(författare)
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Lignin-based carbon fiber : effect of softwood kraft lignin separation method on multifilament melt-spinning performance and conversion
- 2019
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Ingår i: 20th International symposium on wood, fiber, and pulping chemistry.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A reference lignin separated from an industrial softwood kraft black liquor via an improved LignoBoost process was compared to four other lignins derived from the same liquor. The four lignins were produced by using a) pH-fractionation within the LignoBoost process, b) ultrafiltration of black liquor prior to the LignoBoost process, and c) solvent leaching of the reference lignin using methanol and d) ethanol.Lignin compositional characteristics and thermal properties were compared, and monofilament extrusion used to assess their potential for successful melt spinning at the 24 filament scale. The lignin prepared by ethanol leaching of the reference lignin was found to be most appropriate for potential pilot scale fibre production. This was owing to a high purity, lower comparative glass transition temperature (Tg), and good spinning performance.Thermal pretreatments of the ethanol leached lignin gave a selection of enhanced lignins which were characterized for comparison, and melt spun on pilot multifilament equipment. The enhanced lignins could be continuously melt spun giving filaments with diameters as low as 10 μm and with minimal defects. Conversion of selected filaments provided carbon fibres with a tensile strength of 1259 ± 159 MPa, tensile modulus of 67 ± 3 GPa and diameter of 7.3 ± 0.5 μm.
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| 3. |
- Bostan, Lars, et al.
(författare)
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Upscaling of lignin precursor melt spinning by bicomponent spinning and its use for carbon fibre production
- 2021
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Ingår i: Philosophical Transactions. Series A. - : Royal Society Publishing. - 1364-503X .- 1471-2962. ; 379:2209
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Tidskriftsartikel (refereegranskat)abstract
- Upscaling lignin-based precursor fibre production is an essential step in developing bio-based carbon fibre from renewable feedstock. The main challenge in upscaling of lignin fibre production by melt spinning is its melt behaviour and rheological properties, which differ from common synthetic polymers used in melt spinning. Here, a new approach in melt spinning of lignin, using a spin carrier system for producing bicomponent fibres, has been introduced. An ethanol extracted lignin fraction from LignoBoost process of commercial softwood kraft black liquor was used as feedstock. After additional heat treatment, melt spinning was performed in a pilot-scale spinning unit. For the first time, biodegradable polyvinyl alcohol (PVA) was used as a spin carrier to enable the spinning of lignin by improving the required melt strength. PVA-sheath/lignin-core bicomponent fibres were manufactured. Afterwards, PVA was dissolved by washing with water. Pure lignin fibres were stabilized and carbonized, and tensile properties were measured. The measured properties, tensile modulus of 81.1 ± 3.1 GPa and tensile strength of 1039 ± 197 MPa, are higher than the majority of lignin-based carbon fibres reported in the literature. This new approach can significantly improve the melt spinning of lignin and solve problems related to poor spinnability of lignin and results in the production of high-quality lignin-based carbon fibres. This article is part of the theme issue 'Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 2)'. © 2021 The Author(s).
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| 4. |
- Edberg, Jesper, 1988-, et al.
(författare)
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A Forest-Based Triboelectric Energy Harvester
- 2022
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Ingår i: Global Challenges. - : John Wiley and Sons Inc. - 2056-6646. ; 6:10
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Tidskriftsartikel (refereegranskat)abstract
- Triboelectric nanogenerators (TENGs) are a new class of energy harvesting devices that have the potential to become a dominating technology for producing renewable energy. The versatility of their designs allows TENGs to harvest mechanical energy from sources like wind and water. Currently used renewable energy technologies have a restricted number of materials from which they can be constructed, such as metals, plastics, semiconductors, and rare-earth metals. These materials are all non-renewable in themselves as they require mining/drilling and are difficult to recycle at end of life. TENGs on the other hand can be built from a large repertoire of materials, including materials from bio-based sources. Here, a TENG constructed fully from wood-derived materials like lignin, cellulose, paper, and cardboard, thus making it 100% green, recyclable, and even biodegradable, is demonstrated. The device can produce a maximum voltage, current, and power of 232 V, 17 mA m–2, and 1.6 W m–2, respectively, which is enough to power electronic systems and charge 6.5 µF capacitors. Finally, the device is used in a smart package application as a self-powered impact sensor. The work shows the feasibility of producing renewable energy technologies that are sustainable both with respect to their energy sources and their material composition. © 2022 The Authors.
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| 5. |
- Edberg, Jesper, et al.
(författare)
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Laser-induced graphitization of a forest-based ink for use in flexible and printed electronics
- 2020
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Ingår i: npj Flexible Electron.. - : Nature Research. - 2397-4621. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Laser-induced graphitization (LIG) is a method of converting a carbon-rich precursor into a highly conductive graphite-like carbon by laser scribing. This method has shown great promise as a versatile and low-cost patterning technique. Here we show for the first time how an ink based on cellulose and lignin can be patterned using screen printing followed by laser graphitization. Screen printing is one of the most commonly used manufacturing techniques of printed electronics, making this approach compatible with existing processing of various devices. The use of forest-based materials opens the possibility of producing green and sustainable electronics. Pre-patterning of the ink enables carbon patterns without residual precursor between the patterns. We investigated the effect of the ink composition, laser parameters, and additives on the conductivity and structure of the resulting carbon and could achieve low sheet resistance of 3.8 Ω sq-1 and a high degree of graphitization. We demonstrated that the process is compatible with printed electronics and finally manufactured a humidity sensor which uses lignin as the sensing layer and graphitized lignin as the electrodes.
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| 6. |
- Gao, Yu, et al.
(författare)
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Analysis of gas chromatography/mass spectrometry data for catalytic lignin depolymerization using positive matrix factorization
- 2018
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Ingår i: Green Chemistry. - : Royal Society of Chemistry (RSC). - 1463-9262 .- 1463-9270. ; 20:18, s. 4366-4377
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Tidskriftsartikel (refereegranskat)abstract
- Various catalytic technologies are being developed to efficiently convert lignin into renewable chemicals. However, due to its complexity, catalytic lignin depolymerization often generates a wide and complex distribution of product compounds. Gas chromatography/mass spectrometry (GC-MS) is a common analytical technique to profile the compounds that comprise lignin depolymerization products. GC-MS is applied not only to determine the product composition, but also to develop an understanding of the catalytic reaction pathways and of the relationships among catalyst structure, reaction conditions, and the resulting compounds generated. Although a very useful tool, the analysis of lignin depolymerization products with GC-MS is limited by the quality and scope of the available mass spectral libraries and the ability to correlate changes in GC-MS chromatograms to changes in lignin structure, catalyst structure, and other reaction conditions. In this study, the GC-MS data of the depolymerization products generated from organosolv hybrid poplar lignin using a copper-doped porous metal oxide catalyst and a methanol/dimethyl carbonate co-solvent was analyzed by applying a factor analysis technique, positive matrix factorization (PMF). Several different solutions for the PMF model were explored. A 13-factor solution sufficiently explains the chemical changes occurring to lignin depolymerization products as a function of lignin, reaction time, catalyst, and solvent. Overall, seven factors were found to represent aromatic compounds, while one factor was defined by aliphatic compounds.
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| 7. |
- Goliszek, M., et al.
(författare)
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Comparing industrial and analytical kraft lignins as biobased UV-protective additives in coatings
- 2024
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Ingår i: Industrial crops and products (Print). - : Elsevier B.V.. - 0926-6690 .- 1872-633X. ; 214
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Tidskriftsartikel (refereegranskat)abstract
- Lignin as the second most abundant biopolymer on Earth has the potential to become the alternative to petroleum-derived materials. It exhibits excellent UV absorption ability due to its aromatic structure and the presence of numerous phenolic, ketone, and intramolecular hydrogen bonds. Due to its complex nature, it is important to investigate its properties which is a very important step towards the valorization of lignin. Revealing its structural complexity allows for a better examination of its influence on the properties of the final lignin-based materials. In our research, we used two different kraft lignins: commercial analytical kraft lignin (AL) and industrial LignoBoost kraft lignin (KL) as UV-protect additives in BPA(Bisphenol A)-free polymer coatings based on diurethane dimethacrylate (DIUR). The maximum addition of KL and AL was 2 wt%. Both lignin samples were characterized in detail (composition analysis, ash content, molar mass and polydispersity, surface morphology, thermal properties, and quantitative measurement of hydroxyl group content). We investigated the influence of lignins on the textural and thermal properties of the coatings. Finally, we studied the application of lignin as a value-added UV-protective component by UV-Vis electronic absorption spectroscopy. KL with a higher purity and lower number of aliphatic OH had a better dispersion in the polymer matrix than AL lignin which had more agglomeration in the polymer matrix. The better dispersion resulted in producing a smoother surface in the coatings made from KL. Finally, a noticeable and significant impact of KL additive on the photoprotective properties of the coating material was demonstrated. These results showed a potential application and opportunity in the valorization of available industrial lignins toward sustainable and value-added products.
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| 8. |
- Gond, Ritambhara, et al.
(författare)
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A Lignosulfonate Binder for Hard Carbon Anodes in Sodium-Ion Batteries : A Comparative Study
- 2021
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Ingår i: ACS Sustainable Chemistry and Engineering. - : American Chemical Society. - 2168-0485. ; 9:37, s. 12708-
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Tidskriftsartikel (refereegranskat)abstract
- An important factor in the development of sodium-ion batteries (SIBs) is the use of cheap and sustainable materials. Sodium lignosulfonate, a lignin derivative, is demonstrated here as an attractive, "green", water-soluble, and potentially cost-effective binder for use in hard carbon anodes for SIBs. A comparison of its battery cycling performance is made against other binders including sodium carboxymethyl cellulose and lignin, obtained from the kraft process, as well as sodium alginate, derived from algae. Apart from lignin, which requires processing in N-methyl-2-pyrrolidone, the other three binders are water-soluble. Lignosulfonate shows comparable or better performance, with high capacity retention and stability, when using 1 M NaPF6 in propylene carbonate or ethylene carbonate:diethyl carbonate electrolytes for both half- and full-cells (against a Prussian white cathode). Further improvements are observed when including styrene-butadiene rubber as a co-binder. X-ray photoelectron spectroscopy demonstrates similar solid electrolyte interphase compositions after the initial sodium insertion for both lignosulfonate and carboxymethyl cellulose binders. However, after subsequent cycling, the surface layer composition and thickness are found to be dependent on the binder. For the lignosulfonate-based electrode, the layer appears thicker but comprises a smaller fraction of carbon-oxygen species. © 2021 The Authors.
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| 9. |
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| 10. |
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| 11. |
- Liu, Cong, et al.
(författare)
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Effects of nanocrystalline cellulose on the micro-creep properties of phenol formaldehyde resin
- 2018
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Ingår i: Materials Research Express. - : Institute of Physics Publishing. - 2053-1591. ; 5:12
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Tidskriftsartikel (refereegranskat)abstract
- The use of nanocrystalline cellulose (NCC) has become increasingly prevalent in recent years, with limited studies on the the time-dependent characteristics of wood-adhesive composite reinforced by it. To analyze the viscoelasticity of control phenol formaldehyde (PF) resin and wood-resin composites added with three types of NCC, the micro-creep properties of control phenol formaldehyde (PF) resin and PF resin with cellulose nanofibrils (CNF), cellulose microfibrils (CMF), and cellulose nanocrystals (CNC) were investigated by nanoindentation (NI). The sample creep curves proved that adding CNC, CMF, and CNF into the PF resin remarkably impacted the creep properties of the wood-resin sample interface. The cured resin sample had the lowest strength and the most deformation, and the pure wood sample performed slightly better. Among the three NCC-added wood-resin samples, the CNF-added wood-resin sample has the least deformation in the same load and the least permanent deformation after unloading followed by CMF-added and CNC-added wood-resin samples. In the derivative of creep curve function, the depth tendency of CNC-added and CNF-added wood-resin samples showed a gently increasing slope with time in contrast to CMF-added ones. Furthermore, scanning probe microscopy (SPM) images supported that PF resin had filled up the pores of the wood microstructures and strengthened the wood-resin sample in the company of NCC, which was then able to carry the load.
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| 12. |
- Peuvot, Kevin, et al.
(författare)
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Lignin based electrospun carbon fiber anode for sodium ion batteries
- 2019
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Ingår i: Journal of the Electrochemical Society. - : Electrochemical Society Inc.. - 0013-4651 .- 1945-7111. ; 166:10, s. A1984-A1990
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Tidskriftsartikel (refereegranskat)abstract
- Sodium ion batteries (SIBs) are emerging as an alternative battery technology to lithium ion batteries because they have the potential of having a similar energy density and the advantage of sodium being more environmentally friendly than lithium. Hard carbon has been shown to be one of the best candidates as anode material for SIBs. However, several challenges need to be solved before commercializing SIBs such as finding cheaper and more efficient precursors to produce hard carbon and increasing the stability of hard carbon electrodes with the electrolyte. Herein, we report a new bio-based free standing electrode made from lignin based electrospun carbon fibers (LCFs) with a high specific capacity of 310 mAh.g−1 and a first coulombic efficiency of 89%. By using high precision coulometry on the LCFs at different carbonization temperatures, it was found that the cycling stability was dependent on the carbonization temperature. The results show that LCFs are a viable and renewable source to be used as anodes in future SIBs. © The Author(s) 2019.
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| 13. |
- Peuvot, Kevin, et al.
(författare)
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Potassium-ion insertion in lignin-based carbon fibers
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Hard carbon is one the most promising negative electrode materials for potassium-ion batteries (KIBs). However, the structure of hard carbon is complex, made of curved graphene like structures containing defects, heteroatoms, and open and closed pores, and a complete structure model is still lacking. As a result, the potassium-ion insertion mechanism into hard carbon is still under debate. In this work, we analyze the electrochemical behavior of lignin-based carbon fibres (LCFs) electrodes manufactured at different carbonization temperatures. By analyzing the open-circuit voltage curves and entropy change of the insertion reaction, it is found that hard carbon electrodes behave like a blended electrode system in which the capacity contribution of the slope and the plateau regions of the galvanostatic profile can be considered as two separate domains, with different properties. To analyze the voltage relaxation curves, we compare results from both an analytical galvanostatic intermittent titration (GITT) model and an extended finite-element based potassium insertion model in the fibers. In some regions, the model exhibits poor fitting to our experimental results, which indicate shortcomings of using an analytical GITT model for analyzing potassium ion insertion into hard carbon. We propose that, to better predict the voltage relaxation behavior of the system, blended electrode characteristics with at least two domains should be incorporated in future modeling work
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| 14. |
- Rajendra Babu Kalai Arasi, Azega, 1995, et al.
(författare)
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Effect of plasma treatment on electrochemical performance of lignin-based carbon fibers
- 2023
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Ingår i: Journal of Electroanalytical Chemistry. - 1572-6657. ; 946
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Tidskriftsartikel (refereegranskat)abstract
- The abundant and renewable nature of lignin obtained from wood renders it as a sustainable carbon resource for energy storage applications. However, their environmentally unfavorable processing conditions and limited energy storage performance prohibit the use of lignin-based carbon materials' use as supercapacitor electrodes. The material's properties require advancement to overcome the limitation of low specific capacitances. In this study, we report on the impact on the electrochemical performance of inherently hydrophobic lignin-based carbon fibers (LCF) by subjecting them to a mild plasma treatment. The electrode’s capacitance was thus increased by 20%, with better rate capability and energy-power performance (11 Wh/kg and 0.8 kW/kg) in the KOH electrolyte. The quantified improvements were attributed to the capacitive functional groups, and enhanced surface wettability, which increased ion accessibility to active surface area improving charge-transfer ability to the surface with more additional functional groups. Remarkably, the selected plasma conditions introduced mostly desirable functional groups that limited any parasitic faradaic reactions prone to affect the device's long-term cycling stability and self-discharge characteristics. Furthermore, the impact of different inherent and introduced oxygen surface functional groups, including COO−, COH, CO, and CO, on the capacitive performance of these fibers at different device conditions (such as cycling and electrochemical activation) was investigated in different aqueous electrolytes. To ensure environmental favorability, the electrospinning of lignin fibers was conducted using a high molecular fraction of lignin without the inclusion of any fossil-based co-spinning polymers.
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| 15. |
- Ribadeneyra, Maria, et al.
(författare)
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Lignin-derived electrospun freestanding carbons as alternative electrodes for redox flow batteries
- 2020
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Ingår i: Carbon. - : Elsevier Ltd. - 0008-6223 .- 1873-3891. ; 157, s. 847-856
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Tidskriftsartikel (refereegranskat)abstract
- Redox flow batteries represent a remarkable alternative for grid-scale energy storage. They commonly employ carbon felts or carbon papers, which suffer from low activity towards the redox reactions involved, leading to poor performance. Here we propose the use of electrospun freestanding carbon materials derived from lignin as alternative sustainable electrodes for all-vanadium flow batteries. The lignin-derived carbon electrospun mats exhibited a higher activity towards the VO2 +/VO2+ reaction than commercial carbon papers when tested in a three-electrode electrochemical cell (or half-cell), which we attribute to the higher surface area and higher amount of oxygen functional groups at the surface. The electrospun carbon electrodes also showed performance comparable to commercial carbon papers, when tested in a full cell configuration. The modification of the surface chemistry with the addition of phosphorous produced different effect in both samples, which needs further investigation. This work demonstrates for the first time the application of sustainably produced electrospun lignin-derived carbon electrodes in a redox flow cell, with comparable performance to commercial materials and establishes the great potential of biomass-derived carbons in energy devices.
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| 16. |
- Schlee, Philipp, et al.
(författare)
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Free-standing supercapacitors from kraft lignin nanofibers with remarkable volumetric energy density
- 2019
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Ingår i: Chemical Science. - : Royal Society of Chemistry. - 2041-6539. ; 10:10, s. 2980-2988
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Tidskriftsartikel (refereegranskat)abstract
- We have discovered a very simple method to address the challenge associated with the low volumetric energy density of free-standing carbon nanofiber electrodes for supercapacitors by electrospinning Kraft lignin in the presence of an oxidizing salt (NaNO3) and subsequent carbonization in a reducing atmosphere. The presence of the oxidative salt decreases the diameter of the resulting carbon nanofibers doubling their packing density from 0.51 to 1.03 mg cm−2 and hence doubling the volumetric energy density. At the same time, the oxidative NaNO3 salt eletrospun and carbonized together with lignin dissolved in NaOH acts as a template to increase the microporosity, thus contributing to a good gravimetric energy density. By simply adjusting the process parameters (amount of oxidizing/reducing agent), the gravimetric and volumetric energy density of the resulting lignin free-standing carbon nanofiber electrodes can be carefully tailored to fit specific power to energy demands. The areal capacitance increased from 147 mF cm−2 in the absence of NaNO3 to 350 mF cm−2 with NaNO3 translating into a volumetric energy density increase from 949 μW h cm−3 without NaNO3 to 2245 μW h cm−3 with NaNO3. Meanwhile, the gravimetric capacitance also increased from 151 F g−1 without to 192 F g−1 with NaNO3.
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| 17. |
- Schlee, Philipp, et al.
(författare)
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From waste to wealth : From kraft lignin to free-standing supercapacitors
- 2019
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Ingår i: Carbon. - : Elsevier BV. - 0008-6223 .- 1873-3891. ; 145, s. 470-480
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Tidskriftsartikel (refereegranskat)abstract
- Pure eucalyptus Kraft lignin derived carbon fiber mats were produced based on a model workflow. It covers the preparation and characterization of the lignin precursor and the carbon materials and its testing in the final application (supercapacitor). Sequential solvent extraction was employed to produce a eucalyptus Kraft lignin precursor which could be electrospun into lignin fibers without any additives. The fiber formation from low molecular weight lignin is assigned to strong intermolecular interactions via hydrogen bonding and π-π-stacking between individual lignin macromolecules which gives rise to association complexes in the electrospinning solution. By stabilization in air, carbonization in N2 and an activation step in CO2, free-standing microporous carbon fiber mats could be produced. These fiber mats possess mainly basic oxygen functional groups which proved to be beneficial when tested as free-standing electrodes in symmetric supercapacitors. Consequently, the CO2-activated fiber mats showed a high specific gravimetric capacitance of 155 F/g at 0.1 A/g, excellent rate capability with 113 F/g at 250 A/g and good capacitance retention of 94% after 6000 cycles when tested in 6 M KOH electrolyte. Therefore, we conclude that lignin itself is a promising precursor to produce microporous, oxygen functionalized carbon fibers serving as free-standing electrodes in aqueous supercapacitors.
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| 18. |
- Schlee, Philipp, et al.
(författare)
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Hardwood : versus softwood Kraft lignin-precursor-product relationships in the manufacture of porous carbon nanofibers for supercapacitors
- 2020
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Ingår i: Journal of Materials Chemistry A. - : Royal Society of Chemistry. - 2050-7488 .- 2050-7496. ; 8:44, s. 23543-23554
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Tidskriftsartikel (refereegranskat)abstract
- The process of stabilization is essential in the production of carbon fibers from lignins. During stabilization, the initially thermoplastic lignin polymer is converted to a thermoset polymer allowing for high-temperature treatment without a change in shape. In this work, hardwood (HKL) and softwood (SKL) Kraft lignins were stabilized in air at temperatures between 190 and 340 °C before carbonization at 800 °C in a nitrogen atmosphere. Due to the differences in side-chain linkages, functional groups and molar mass, the lignins exhibit different structural changes upon stabilization and hence develop different porosities upon carbonization. Both lignins undergo major crosslinking reactions in the side chains at low temperatures and degradation reactions at high temperatures during stabilization. Crosslinking gives rise to narrow pore size distributions with mainly (sub-) nanometer pores, whereas degradation reactions lead to a more open pore structure with additional mesoporosity (>2 nm). When both types of reactions take place simultaneously, highly accessible (sub-) nanoporosity can be effectively created, which boosts the performance of supercapacitors operating in 6 M KOH(aq). This effect terminates when the crosslinking reactions cease and mainly degradation reactions take place, which occurs in HKL at 340 °C. SKL shows both a lower degree of crosslinking and degradation and hence develops less specific surface area. The optimum performance in an aqueous alkaline supercapacitor is achieved with HKL stabilized at 310 °C. It shows a specific gravimetric capacitance of 164 F g-1 at 0.1 A g-1 and 119 F g-1 at 250 A g-1 with a capacitance retention of more than 90% after 10 000 cycles.
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| 19. |
- Thielke, M. W., et al.
(författare)
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Full Lignin-Derived Electrospun Carbon Materials as Electrodes for Supercapacitors
- 2022
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Ingår i: Frontiers in Materials. - : Frontiers Media S.A.. - 2296-8016. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- In the search for more sustainable energy storage devices, biomass-derived materials have been widely researched as carbon source for electrode applications. Here we present the processing of high molecular lignin, an abundant carbon rich biopolymer and byproduct of the pulp and paper industry, into freestanding nonwoven carbon fiber (CNFs) electrodes by using electrospinning. It is worth mentioning that no petrol-derived polymers that are usually included in the electrospinning of lignin, were employed in this work, making these electrodes more sustainable than common lignin-derived carbon electrodes. The effect of the carbonization temperature and oxygen plasma treatment in the electrochemical performance of the CNFs as electrodes for supercapacitors was studied. The upscaling of the processing of lignin into carbon electrodes was also explored by comparing a standard electrospinning set up with a needleless electrospinning equipment that enabled faster and higher throughput. The electrochemical performance of the CNFs increased after plasma treatment of the surface and the electrodes prepared using the standard set up exhibited the highest activity, achieving specific capacitances of up to 103.6 F g−1. Copyright © 2022 Thielke, Lopez Guzman, Victoria Tafoya, García Tamayo, Castro Herazo, Hosseinaei and Sobrido.
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| 20. |
- Titirici, M., et al.
(författare)
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The sustainable materials roadmap
- 2022
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Ingår i: Journal of Physics. - : Institute of Physics. - 2515-7639. ; 5:3
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Tidskriftsartikel (refereegranskat)abstract
- Over the past 150 years, our ability to produce and transform engineered materials has been responsible for our current high standards of living, especially in developed economies. However, we must carefully think of the effects our addiction to creating and using materials at this fast rate will have on the future generations. The way we currently make and use materials detrimentally affects the planet Earth, creating many severe environmental problems. It affects the next generations by putting in danger the future of the economy, energy, and climate. We are at the point where something must drastically change, and it must change now. We must create more sustainable materials alternatives using natural raw materials and inspiration from nature while making sure not to deplete important resources, i.e. in competition with the food chain supply. We must use less materials, eliminate the use of toxic materials and create a circular materials economy where reuse and recycle are priorities. We must develop sustainable methods for materials recycling and encourage design for disassembly. We must look across the whole materials life cycle from raw resources till end of life and apply thorough life cycle assessments (LCAs) based on reliable and relevant data to quantify sustainability. We need to seriously start thinking of where our future materials will come from and how could we track them, given that we are confronted with resource scarcity and geographical constrains. This is particularly important for the development of new and sustainable energy technologies, key to our transition to net zero. Currently ‘critical materials’ are central components of sustainable energy systems because they are the best performing. A few examples include the permanent magnets based on rare earth metals (Dy, Nd, Pr) used in wind turbines, Li and Co in Li-ion batteries, Pt and Ir in fuel cells and electrolysers, Si in solar cells just to mention a few. These materials are classified as ‘critical’ by the European Union and Department of Energy. Except in sustainable energy, materials are also key components in packaging, construction, and textile industry along with many other industrial sectors. This roadmap authored by prominent researchers working across disciplines in the very important field of sustainable materials is intended to highlight the outstanding issues that must be addressed and provide an insight into the pathways towards solving them adopted by the sustainable materials community. In compiling this roadmap, we hope to aid the development of the wider sustainable materials research community, providing a guide for academia, industry, government, and funding agencies in this critically important and rapidly developing research space which is key to future sustainability. © 2022 The Author(s).
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| 21. |
- Tomani, Per, et al.
(författare)
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Learnings and Aspects on Kraft Lignin Separation and Valorisation
- 2022
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Ingår i: The 10th Nordic Wood Biorefinery Conference. - Helsinki. - 9789513887728 ; , s. 29-29
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Process-integrated, continuous, separation of lignin from kraft pulp mills which results in a ligninwith low ash content (0.05-1 %) is relatively new technology compared to traditional kraft pulping subprocesses,like recovery boilers, lime kilns, white liquor preparation etc. The LignoBoost technology wasdemonstrated in 2007 and the first commercial full-scale process started in 2013, delivered to Domtarby Valmet. This means that this concept now has been in commercial scale operation for almost 10years. There is also an alternative commercialized concept available today from another supplier,NORAM International. The idea to integrate lignin separation into a kraft pulp mill is today quite provencommercial technology.This paper will discuss different learnings, experiences, from the early development of theLignoBoost process, which includes handling of the separated lignin followed by drying. The dustexplosion risk is relatively high for dry kraft lignin due to a high kst value – so the paper will also discussif there are opportunities to reduce this risk. The paper will also briefly discuss promising productsegments for kraft lignin.
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