| 1. |
- Han, Ning, et al.
(författare)
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Achieving Efficient Electrocatalytic Oxygen Evolution in Acidic Media on Yttrium Ruthenate Pyrochlore through Cobalt Incorporation
- 2023
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Ingår i: Advanced Functional Materials. - : Wiley. - 1616-301X .- 1616-3028. ; 33:20
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Tidskriftsartikel (refereegranskat)abstract
- The development of electrocatalysts for the oxygen evolution reaction (OER) especially in acidic media remains the major challenge that still requires significant advances, both in material design and mechanistic exploration. In this study, the incorporation of cobalt in Y2-xCoxRu2O7−δ results in an ultrahigh OER activity because of the charge redistribution at eg orbitals between Ru and Co atoms. The Y1.75Co0.25Ru2O7−δ electrocatalyst exhibits an extremely small overpotential of 275 mV in 0.5 m H2SO4 at the current density of 10 mA cm−2, which is smaller than that of parent Y2Ru2O7−δ (360 mV) and commercial RuO2 (286 mV) catalysts. The systematic investigation of the composition related to OER activity shows that the Co substitution will also bring other effective changes, such as reducing the bandgap, and creating oxygen vacancies, which result in fast OER charge transfer. Meanwhile, the strengthening of the bond hybridization between the d orbitals of metal (Y and Ru) and the 2p orbitals of O will intrinsically enhance the chemical stability. Finally, theoretical calculations indicate that cobalt substitution reduces the theoretical overpotential both through an adsorbate evolution mechanism and a lattice oxygen-mediated mechanism.
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| 2. |
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| 3. |
- Zhang, Wei, et al.
(författare)
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Balancing Adsorption, Catalysis, and Desorption in Cathode Catalyst For Li–S Batteries
- 2023
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Ingår i: Advanced Energy Materials. - 1614-6832 .- 1614-6840. ; 13:43
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Tidskriftsartikel (refereegranskat)abstract
- The complicated electrochemical catalytic conversion process of polysulfides in metal–sulfur batteries involves three steps: adsorption, catalysis, and desorption process. Even as huge efforts are made for the understanding of the separate steps (especially for the adsorption and catalysis process), research focusing on the entire process is still scarce. Herein, a series of cobalt phosphides (CoP, CoP2, and CoP3) is employed with identical hollow morphology as model electrocatalysts to investigate the significance of the desorption process and discuss the balancing among the adsorption, catalysis, and desorption of lithium polysulfides (LiPSs). The experimental data demonstrate that, compared to CoP and CoP3, CoP2 exhibits moderate adsorption of LiPSs, which enhances the reduction kinetics of S8 to Li2S and regulates the desorption of short-chain LiPSs. Theoretical calculations further confirm that CoP2 with moderate adsorption of LiPSs exhibits better redox kinetics of LiPSs compared to CoP and CoP3. Moderate adsorption enables the CoP2-based sulfur cathode to deliver excellent stability with 86% capacity retention (2.6 and 2.0 times higher than CoP and CoP3, respectively) over 1000 cycles at 1 C. All these results indicate that in the adsorption-catalysis-desorption chain for LiPSs, all steps need to be considered rather than just focusing on one step of the process.
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| 4. |
- Chai, Jiali, et al.
(författare)
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Insights on Titanium-based chalcogenides TiX2 (X = O, S, Se) as LIBs/SIBs anode materials
- 2023
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947 .- 1873-3212. ; 453
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Forskningsöversikt (refereegranskat)abstract
- Ti-based chalcogenides TiX2 (X = O, S, Se) are widely used in the research of battery electrode materials due to its excellent rate performance and good chemical stability. In this paper, in order to improve the electrochemical performance of lithium-ion batteries (LIBs) and sodium ion batteries (SIBs), and further improve the application prospect of batteries, the strategies for design and preparation of LIBs/SIBs anode materials for Ti-based chalcogenides TiX2 (X = O, S, Se) are reviewed. The effects of the internal morphology modification, surface structure vacancy and composite with other material of TiX2 (X = O, S, Se) as LIBs/SIBs anode materials are analyzed in detail. On this basis, the application prospect of TiX2 (X = O, S, Se) as LIBs/SIBs anode is prospected, it is expected to fill the research of diversified applications of LIBs/SIBs anode materials.
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