| 1. |
- Fan, Ke, et al.
(författare)
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Amorphous WO3 induced lattice distortion for a low-cost and high-efficient electrocatalyst for overall water splitting in acid
- 2020
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Ingår i: Sustainable Energy & Fuels. - : ROYAL SOC CHEMISTRY. - 2398-4902. ; 4:4, s. 1712-1722
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Tidskriftsartikel (refereegranskat)abstract
- The development of highly active and durable catalysts for water oxidation under acidic conditions is necessary but challenging for renewable energy conversion. Ir-based catalysts are highly efficient for water oxidation in acid, but their large scale application is hindered by the high cost and scarcity of iridium. Herein, we use an amorphous WO3 induced lattice distortion (AWILD) strategy to reduce the Ir content to only 2 wt% in the final material. The optimized hybrid nitrogen-doped carbon (NC)/WO3/IrO2 can efficiently catalyze water oxidation with a low overpotential of 270 mV at 10 mA cm(-2) current density (eta (10)) and a high turnover frequency of over 2 s(-1) at 300 mV overpotential in 0.5 M H2SO4, a performance that surpasses that of commercial IrO2 significantly. Introducing the layer of amorphous WO3 between IrO2 nanoparticles and NC can distort the lattice of IrO2, exposing more highly active sites for water oxidation. The AWILD effect compensates for the lower Ir content and dramatically reduces the cost of the catalyst without sacrificing the catalytic activity. Additionally, this catalyst also exhibits high activity in acid for hydrogen evolution with only 65 mV of eta (10) attributed to the AWILD effect, exhibiting efficient bifunctionality as a Janus catalyst for overall water splitting. The AWILD approach provides a novel and efficient strategy for low-cost and highly efficient electrocatalysts for acidic overall water splitting with an extremely low content of noble metals.
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| 2. |
- Fan, Ke, et al.
(författare)
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Sacrificial W Facilitates Self-Reconstruction with Abundant Active Sites for Water Oxidation
- 2022
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Ingår i: Marine and Petroleum Geology. - : Wiley. - 0264-8172 .- 1873-4073. ; 138
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Tidskriftsartikel (refereegranskat)abstract
- Water oxidation is an important reaction for multiple renewable energy conversion and storage-related devices and technologies. High-performance and stable electrocatalysts for the oxygen evolution reaction (OER) are urgently required. Bimetallic (oxy)hydroxides have been widely used in alkaline OER as electrocatalysts, but their activity is still not satisfactory due to insufficient active sites. In this research, A unique and efficient approach of sacrificial W to prepare CoFe (oxy)hydroxides with abundant active species for OER is presented. Multiple ex situ and operando/in situ characterizations have validated the self-reconstruction of the as-prepared CoFeW sulfides to CoFe (oxy) hydroxides in alkaline OER with synchronous W etching. Experiments and theoretical calculations show that the sacrificial W in this process induces metal cation vacancies, which facilitates the in situ transformation of the intermediate metal hydroxide to CoFe-OOH with more high-valence Co(III), thus creating abundant active species for OER. The Co(III)-rich environment endows the in situ formed CoFe oxyhydroxide with high catalytic activity for OER on a simple flat glassy carbon electrode, outperforming those not treated by the sacrificial W procedure. This research demonstrates the influence of etching W on the electrocatalytic performance, and provides a low-cost means to improve the active sites of the in situ self-reconstructed bimetallic oxyhydroxides for OER.
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| 3. |
- Fan, Lizhou, et al.
(författare)
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2D MnOx composite catalysts inspired by natural OEC for efficient catalyticwater oxidation
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Birnessite MnOx is a close inorganic model of natural oxygen-evolving complex (OEC) that hasbeen widely investigated for catalytic water oxidation, yet its activity is limited by the pooractive site exposure and sluggish charge transfer. Herein, starting from typical birnessite MnOx,we fabricated a hybrid of 2D manganese oxide nanosheets and pyridyl modified graphene(MnOx-NS/py-G) for electrocatalytic water oxidation. Benefiting from the synergy of structuralexfoliation, graphene substrate and molecular pyridyl modification, the MnOx-NS/py-G exhibitsabundant catalytically active sites exposure, fast electron transport, and promoted proton transferat catalyst surface, which imitates the key features of natural OEC. Consequently, theMnOx-NS/py-G reached over 600 times higher activity compared to the typical birnessite MnOx.Inspired by nature, this work provides a well-designed and effective strategy to develop highlyactive manganese oxide-based water oxidation catalysts.
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| 4. |
- Fan, Lizhou, et al.
(författare)
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Holistic functional biomimetics : a key to make an efficient electrocatalyst for water oxidation
- 2023
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Ingår i: Journal of Materials Chemistry A. - : Royal Society of Chemistry (RSC). - 2050-7488 .- 2050-7496. ; 11:20, s. 10669-10676
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Tidskriftsartikel (refereegranskat)abstract
- Water oxidation is the holy grail reaction of natural and artificial photosynthesis. How to design an efficient water-oxidation catalyst remains a long-term challenge for solar fuel production. The rate of water oxidation in photosystem II by the oxygen-evolving complex (OEC) Mn4CaO5 cluster is as high as 100-400 s−1. Mimicking the structures of the OEC is a straightforward strategy to design water-oxidation catalysts. However, the high efficiency of the OEC relies on not only its highly active site but also its holistic system for well-organized electron transfer and proton transport. Lacking such a holistic functional system makes δ-MnO2 a poor water-oxidation catalyst, although the local structure of δ-MnO2 is similar to that of the Mn4CaO5 cluster. Electrocatalysts simultaneously imitating the catalytically active sites, fast electron transfer, and promoted proton transport in a natural OEC have been rarely reported. The significance of the synergy of a holistic system is underrated in the design of water-oxidation catalysts. In this work, we fabricated holistic functional biomimetic composites of two-dimensional manganese oxide nanosheets and pyridyl-modified graphene (MnOx-NS/py-G) for electrocatalytic water oxidation. MnOx-NS/py-G simultaneously imitates the synergy of catalytically active sites, fast electron transfer, and promoted proton transport in a natural OEC, resulting in overall 600 times higher activity than that of typical δ-MnO2. This work demonstrates the significance of holistic functional biomimetic design and guides the development of highly active electrocatalysts for small molecule activation related to solar energy storage.
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| 5. |
- Fan, Lizhou, et al.
(författare)
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3D Core-Shell NiFeCr Catalyst on a Cu Nanoarray for Water Oxidation : Synergy between Structural and Electronic Modulation
- 2018
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Ingår i: ACS Energy Letters. - : AMER CHEMICAL SOC. - 2380-8195. ; 3:12, s. 2865-2874
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Tidskriftsartikel (refereegranskat)abstract
- Low cost transition metal-based electrocatalysts for water oxidation and understanding their structure-activity relationship are greatly desired for clean and sustainable chemical fuel production. Herein, a core-shell (CS) NiFeCr metal/metal hydroxide catalyst was fabricated on a 3D Cu nanoarray by a simple electrodeposition-activation method. A synergistic promotion effect between electronic structure modulation and nanostructure regulation was presented on a CS-NiFeCr oxygen evolution reaction (OER) catalyst: the 3D nanoarchitecture facilitates the mass transport process, the in situ formed interface metal/metal hydroxide heterojunction accelerates the electron transfer, and the electronic structure modulation by Cr incorporation improves the reaction kinetics. Benefiting from the synergy between structural and electronic modulation, the catalyst shows excellent activity toward water oxidation under alkaline conditions: overpotential of 200 mV at 10 mA/cm(2) current density and Tafel slope of 28 mV/dec. This work opens up a new window for understanding the structure-activity relationship of OER catalysts and encourages new strategies for development of more advanced OER catalysts.
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| 6. |
- Fan, Lizhou, et al.
(författare)
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Molecular Functionalization of NiO Nanocatalyst for Enhanced Water Oxidation by Electronic Structure Engineering
- 2020
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Ingår i: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 13:22, s. 5901-5909
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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.
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| 7. |
- Fan, Lizhou, et al.
(författare)
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Promoting the Fe(VI) active species generation by structural and electronic modulation of efficient iron oxide based water oxidation catalyst without Ni or Co
- 2020
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Ingår i: Nano Energy. - : Elsevier BV. - 2211-2855 .- 2211-3282. ; 72
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Tidskriftsartikel (refereegranskat)abstract
- Fe is considered as a promising alternative for OER catalysts owing to its high natural abundance and low cost. Due to the low conductivity and sluggish catalytic kinetics, the catalytic efficiency of Fe-rich catalysts is far from less abundant Ni, Co-rich alternatives and has been hardly improved without the involvement of Ni or Co. The lower activity of Fe-rich catalysts renders the real active center of state-of-the-art NiFe, CoFe catalyst in long-term scientific debate, despite of detection of Fe-based active intermediates in these catalysts during catalytic process. In the present work, we fabricated a series of sub-5 nm Fe1-yCryOx nanocatalysts via a simple solvothermal method, achieving systematically promoted high-valent Fe(VI) species generation by structural and electronic modulation, displaying highly active OER performance without involvement of Ni or Co. Detailed investigation revealed that the high OER activity is related to the ultrasmall nanoparticle size that promotes abundant edge- and corner-site exposure at catalyst surface, which involves in OER as highly reactive site; and the incorporated Cr ions that remarkably accelerate the charge transfer kinetics, providing an effective conduit as well as suitable host for high-valent active intermediate. This work reveals the structural prerequisites for efficient Fe-rich OER catalyst fabrication, inspiring deeper understanding of the structure-activity relationship as well as OER mechanism of Fe-based catalysts.
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| 8. |
- Fan, Lizhou
(författare)
-
Towards Artificial Photosynthesis: Exploration of Efficient First-Row Transition Metal-Based Water Oxidation Catalysts
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Artificial photosynthesis provides a promising strategy for sustainable energy harvesting, yet its overall efficiency is limited by the water oxidation reaction. The subject of this thesis focuses on the exploration of highly efficient cost-effective heterogeneous catalysts for water oxidation, and the investigation of essential catalyst structure-activity relationships.Chapters 1 and 2 present a brief introduction on heterogeneous catalysts for water oxidation, including selected state-of-the-art catalysts, methodologies for activity improvement, and mechanistic investigations. The characterization methods used in this thesis are also demonstrated.In chapter 3, a molecular functionalization approach is developed to rationally modify the electronic structure of NiO catalyst, by which the water oxidation activity is systematically tailored. These studies correspond to the question: “How to rationally adjust the catalytic performance of heterogeneous catalysts?”In chapter 4, to lower the catalyst cost, a Fe-based Fe0.65Cr0.35Ox nanocatalyst is fabricated by structural and electronic modulation, which shows considerable water oxidation activity. These studies target the question: “How to fabricate an efficient Fe-based water oxidation catalyst?”In chapter 5, a bio-inspired Mn-based catalyst is presented. The catalyst successfully imitates the key features of the natural oxygen evolving complex, achieving dramatically improved water oxidation activity. These studies correspond to the question: “How to improve the catalytic activity of Mn-based water oxidation catalysts?”Finally, in chapter 6, a 3D NiFeCr/Cu nanoarray electrode is constructed by structural engineering, which exhibits extremely high water oxidation activity. These studies correspond to the question: “How to fabricate an efficient catalytic electrode for water oxidation?”
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| 9. |
- Guo, Yaxiao, et al.
(författare)
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Boosting nitrogen reduction reaction by bio-inspired FeMoS containing hybrid electrocatalyst over a wide pH range
- 2019
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Ingår i: Nano Energy. - : Elsevier. - 2211-2855 .- 2211-3282. ; 62, s. 282-288
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Tidskriftsartikel (refereegranskat)abstract
- A facile preparation of bio-inspired and morphology controllable catalytic electrode FeS@MoS2/CFC, featuring a carbon fiber cloth (CFC) covered with FeS dotted MoS2 nanosheets, has been established. Synergy between the CFC as a self-standing conductive substrate and the FeS nanoparticle dotted MoS2 nanosheets with abundant active sites makes the noble-metal-free catalytic electrode FeS@MoS2/CFC highly efficient in nitrogen reduction reaction (NRR), with an ammonia production rate of 8.45 mu g h(-1) cm(-2) and excellent long-term stability at -0.5 V in pH neutral electrolyte. Further electrolysis in acidic and alkaline electrolytes revealed the overall NRR catalytic activity of this electrode over a wide pH range.
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| 10. |
- Guo, Yaxiao, et al.
(författare)
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Molybdenum and boron synergistically boosting efficient electrochemical nitrogen fixation
- 2020
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Ingår i: Nano Energy. - : Elsevier Ltd. - 2211-2855 .- 2211-3282. ; 78
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Tidskriftsartikel (refereegranskat)abstract
- Ammonia production consumes ~2% of the annual worldwide energy supply, therefore strategic alternatives for the energy-intensive ammonia synthesis through the Haber-Bosch process are of great importance to reduce our carbon footprint. Inspired by MoFe-nitrogenase and the energy-efficient and industrially feasible electrocatalytic synthesis of ammonia, we herein establish a catalytic electrode for artificial nitrogen fixation, featuring a carbon fiber cloth fully grafted by boron-doped molybdenum disulfide (B-MoS2/CFC) nanosheets. An excellent ammonia production rate of 44.09 μg h–1 cm–2 is obtained at −0.2 V versus the reversible hydrogen electrode (RHE), whilst maintaining one of the best reported Faradaic efficiency (FE) of 21.72% in acidic aqueous electrolyte (0.1 M HCl). Further applying a more negative potential of −0.25 V renders the best ammonia production rate of 50.51 μg h–1 cm–2. A strong-weak electron polarization (SWEP) pair from the different electron accepting and back-donating capacities of boron and molybdenum (2p shell for boron and 5d shell for molybdenum) is proposed to facilitate greatly the adsorption of non-polar dinitrogen gas via N≡N bond polarization and the first protonation with large driving force. In addition, for the first time a visible light driven photo-electrochemical (PEC) cell for overall production of ammonia, hydrogen and oxygen from water + nitrogen, is demonstrated by coupling a bismuth vanadate BiVO4 photo-anode with the B-MoS2/CFC catalytic cathode.
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| 11. |
- Meng, Qijun, et al.
(författare)
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Efficient BiVO4 Photoanodes by Postsynthetic Treatment : Remarkable Improvements in Photoelectrochemical Performance from Facile Borate Modification
- 2019
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Ingår i: Angewandte Chemie International Edition. - : Wiley-VCH Verlagsgesellschaft. - 1433-7851 .- 1521-3773. ; 58:52, s. 19027-19033
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Tidskriftsartikel (refereegranskat)abstract
- Water-splitting photoanodes based on semiconductor materials typically require a dopant in the structure and co-catalysts on the surface to overcome the problems of charge recombination and high catalytic barrier. Unlike these conventional strategies, a simple treatment is reported that involves soaking a sample of pristine BiVO4 in a borate buffer solution. This modifies the catalytic local environment of BiVO4 by the introduction of a borate moiety at the molecular level. The self-anchored borate plays the role of a passivator in reducing the surface charge recombination as well as that of a ligand in modifying the catalytic site to facilitate faster water oxidation. The modified BiVO4 photoanode, without typical doping or catalyst modification, achieved a photocurrent density of 3.5 mA cm−2 at 1.23 V and a cathodically shifted onset potential of 250 mV. This work provides an extremely simple method to improve the intrinsic photoelectrochemical performance of BiVO4 photoanodes.
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| 12. |
- Meng, Qijun, 1990-, et al.
(författare)
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Remarkable synergy of borate and interfacial hole transporter on BiVO4 photoanodes for photoelectrochemical water oxidation
- 2021
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Ingår i: Materials Advances. - : Royal Society of Chemistry (RSC). - 2633-5409. ; 2:13, s. 4323-4332
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Tidskriftsartikel (refereegranskat)abstract
- Bismuth vanadate (BiVO4) is one of the most fascinating building blocks for the design and assembly of highly efficient artificial photosynthesis devices for solar water splitting. Our recent report has shown that borate treated BiVO4 (B-BiVO4) results in an improved water oxidation performance. In this study, further improvement of both the photoelectrochemical (PEC) activity and stability of B-BiVO4 was successfully achieved by introducing NiFeV LDHs as an oxygen evolution catalyst and interfacial hole transporter. Benefiting from the synergistic effect of co-catalyst and borate pretreatment, the as-prepared NiFeV/B-BiVO4 exhibited a high photocurrent density of 4.6 mA cm−2 at 1.23 VRHE and an outstanding onset potential of ∼0.2 VRHE with good long-term stability. More importantly, NiFeV was found to play a pivotal role in the critically efficient suppression of charge combination on the BiVO4 surface and acceleration of charge transfer rather than a mere electrocatalyst for water oxidation.
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| 13. |
- Sheng, Xia, et al.
(författare)
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Hierarchical micro-reactor as electrodes for water splitting by metal rod tipped carbon nanocapsule self-assembly in carbonized wood
- 2020
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Ingår i: Applied Catalysis B. - : Elsevier. - 0926-3373 .- 1873-3883. ; 264
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Tidskriftsartikel (refereegranskat)abstract
- Materials design of efficient electrochemical micro-reactors is challenging, although hierarchically structured, self-standing electrodes with catalyst arrays offer promise. Herein, catalyst function in compact micro-reactor electrodes is designed by nanostructural tailoring of carbonized wood for efficient water splitting. Specifically, NiFe rod tipped, N-doped graphitic carbon nanocapsule arrays are self-assembled in hierarchical wood, and the benefit of this unique presentation and its promotive effect on accessibility of the catalyst surfaces is apparent. This report also comprises the first wood based micro-reactor electrodes for electrocatalytic water oxidation demonstrating excellent performance. The overpotential for oxygen evolution reaction was as low as 180 mV for 10 mA cm−2 current density and TOFredox was high at a level of 5.8 s−1 (at 370 mV overpotential). This hierarchical electrode can also work as bifunctional catalyst (both as anodic and as cathodic electrode) for total water splitting with a cell potential of 1.49 V for 10 mA cm−2 in alkaline solution, suggestive of their potential also in other electrochemical applications.
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| 14. |
- Zhang, Biaobiao, et al.
(författare)
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Advancing Proton Exchange Membrane Electrolyzers with Molecular Catalysts
- 2020
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Ingår i: Joule. - : Elsevier BV. - 2542-4351. ; 4:7, s. 1408-1444
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Forskningsöversikt (refereegranskat)abstract
- Molecular catalysts possess numerous advantages over conventional heterogeneous catalysts in precise structure regulation, in-depth mechanism understanding, and efficient metal utilization. Various molecular catalysts have been reported that efficiently catalyze reactions involved in artificial photosynthesis, however, these catalysts have been rarely considered in view of practical applications. With this review, firstly we demonstrate in the introduction that molecular catalysts can bring new opportunities to proton exchange membrane (PEM) electrolyzers. In the following parts, we provide an overview of molecular catalyst modified carbon materials developed for electrochemical water oxidation, proton reduction, and CO2 reduction reactions. These materials and the involved immobilization strategies as well as characterization techniques may be directly employed in the investigations of application of molecular catalysts in PEM electrolyzers. The future scientific perspectives and challenges to advance this promising, yet underdeveloped technology for solar fuel production, integrating PEM electrolyzer with molecular-level catalysis, are discussed in the conclusions.
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| 15. |
- Zhang, Biaobiao, et al.
(författare)
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Electrocatalytic Water Oxidation Promoted by 3 D Nanoarchitectured Turbostratic Δ-MnOx on Carbon Nanotubes
- 2017
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Ingår i: ChemSusChem. - : Wiley-VCH Verlag. - 1864-5631 .- 1864-564X. ; 10:22, s. 4472-4478
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Tidskriftsartikel (refereegranskat)abstract
- The development of manganese-based water oxidation electrocatalysts is desirable for the production of solar fuels, as manganese is earth-abundant, inexpensive, non-toxic, and has been employed by the Photosystem II in nature for a billion years. Herein, we directly constructed a 3 D nanoarchitectured turbostratic δ-MnOx on carbon nanotube-modified nickel foam (MnOx/CNT/NF) by electrodeposition and a subsequent annealing process. The MnOx/CNT/NF electrode gives a benchmark catalytic current density (10 mA cm−2) at an overpotential (η) of 270 mV under alkaline conditions. A steady current density of 19 mA cm−2 is obtained during electrolysis at 1.53 V for 1.0 h. To the best of our knowledge, this work represents the most efficient manganese-oxide-based water oxidation electrode and demonstrates that manganese oxides, as a structural and functional model of oxygen-evolving complex (OEC) in Photosystem II, can also become comparable to those of most Ni- and Co-based catalysts.
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| 16. |
- Zhang, Biaobiao, et al.
(författare)
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Identifying MnVII-oxo Species during Electrochemical Water Oxidation by Manganese Oxide
- 2018
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Ingår i: iScience. - : Elsevier BV. - 2589-0042. ; 4, s. 144-152
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Tidskriftsartikel (refereegranskat)abstract
- Identifying surface active intermediate species is essential to reveal the catalytic mechanism of water oxidation by metal-oxides-based catalysts and to develop more efficient catalysts for oxygen-oxygen bond formation. Here we report, through electrochemical methods and ex situ infrared spectroscopy, the identification of a MnVII = O intermediate during catalytic water oxidation by a c-disordered δ-MnOx with an onset-potential-dependent reduction peak at 0.93 V and an infrared peak at 912 cm−1. This intermediate is proved to be highly reactive and much more oxidative than permanganate ion. Therefore, we propose a new catalytic mechanism for water oxidation catalyzed by Mn oxides, with involvement of the MnVII = O intermediate in a resting state and the MnIV−O−MnVII = O as a real active species for oxygen-oxygen bond formation. Inorganic Chemistry; Surface Science; Energy Materials; Electrocatalysis.
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| 17. |
- Zhang, Biaobiao, et al.
(författare)
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Temperature dependence of electrocatalytic water oxidation : a triple device model with a photothermal collector and photovoltaic cell coupled to an electrolyzer
- 2017
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Ingår i: Faraday discussions. - : Royal Society of Chemistry. - 1359-6640 .- 1364-5498. ; 198, s. 169-179
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Tidskriftsartikel (refereegranskat)abstract
- A water oxidation electrocatalyst with high activity is essential for promoting the overall efficiency of an integrated water splitting device. Herein, by investigating the prominent temperature dependence of electrocatalytic water oxidation catalyzed by first row transition metal oxides, we present how to elevate the operating temperature of the electrolyzer as an effective and universal method to improve its electrocatalytic performance. Consequently, a triple device model combining a photothermal collector with a photovoltaic (PV) cell coupled to a water splitting device is proposed to realize the comprehensive and efficient utilization of solar energy: solar heat + PV + electrolyzer.
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| 18. |
- Zhang, Peili, et al.
(författare)
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Dendritic core-shell nickel-iron-copper metal/metal oxide electrode for efficient electrocatalytic water oxidation
- 2018
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Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Electrochemical water splitting requires efficient water oxidation catalysts to accelerate the sluggish kinetics of water oxidation reaction. Here, we report a promisingly dendritic core-shell nickel-iron-copper metal/metal oxide electrode, prepared via dealloying with an electrodeposited nickel-iron-copper alloy as a precursor, as the catalyst for water oxidation. The as-prepared core-shell nickel-iron-copper electrode is characterized with porous oxide shells and metallic cores. This tri-metal-based core-shell nickel-iron-copper electrode exhibits a remarkable activity toward water oxidation in alkaline medium with an overpotential of only 180 mV at a current density of 10 mA cm-2. The core-shell NiFeCu electrode exhibits pH-dependent oxygen evolution reaction activity on the reversible hydrogen electrode scale, suggesting that non-concerted proton-electron transfers participate in catalyzing the oxygen evolution reaction. To the best of our knowledge, the as-fabricated core-shell nickel-iron-copper is one of the most promising oxygen evolution catalysts.
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| 19. |
- Zhang, Peili, et al.
(författare)
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Paired Electrocatalytic Oxygenation and Hydrogenation of Organic Substrates with Water as the Oxygen and Hydrogen Source
- 2019
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Ingår i: Angewandte Chemie International Edition. - : Wiley-VCH Verlagsgesellschaft. - 1433-7851 .- 1521-3773. ; 58:27, s. 9155-9159
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Tidskriftsartikel (refereegranskat)abstract
- The use of water as an oxygen and hydrogen source for the paired oxygenation and hydrogenation of organic substrates to produce valuable chemicals is of utmost importance as a means of establishing green chemical syntheses. Inspired by the active Ni3+ intermediates involved in electro-catalytic water oxidation by nickel-based materials, we prepared NiBx as a catalyst and used water as the oxygen source for the oxygenation of various organic compounds. NiBx was further employed as both an anode and a cathode in a paired electrosynthesis cell for the respective oxygenation and hydrogenation of organic compounds, with water as both the oxygen and hydrogen source. Conversion efficiency and selectivity of >= 99% were observed during the oxygenation of 5-hydroxy-methylfurfural to 2,5-furandicarboxylic acid and the simultaneous hydrogenation of p-nitrophenol to p-aminophenol. This paired electrosynthesis cell has also been coupled to a solar cell as a stand-alone reactor in response to sunlight.
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