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Zhenhai Lai

Bio: Zhenhai Lai is an academic researcher from The Chinese University of Hong Kong. The author has contributed to research in topics: Spin states. The author has co-authored 1 publications.
Topics: Spin states

Papers
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Journal ArticleDOI
TL;DR: In this article, Mn substitution was introduced to LaCoO3, which brought about lattice expansion and reduced crystalline field splitting energy, which led to the increase in the effective magnetic moment, which triggered the transfer of Co3+ from low to higher spin states.
Abstract: Designing efficient oxygen evolution reaction (OER) electrocatalysts is essential for numerous sustainable energy conversion technologies. An obstacle that impedes the development of OER electrocatalysts is the insufficient emphasis on the spin attribution of electrons. Recently, the different spin configuration of reactants and products in the OER has been recognized as the factor that slows down the reaction kinetics. In this work, Mn substitution was introduced to LaCoO3, which brought about lattice expansion and reduced crystalline field splitting energy. This led to the increase in the effective magnetic moment, which triggers the transfer of Co3+ from low to higher spin states. Thus, the hybridization of Co eg and O 2p states across the Fermi level was strengthened. Specifically, with 25 at. % Mn substitution, LaCoO3 transits from a semiconductor to a half-metal, which benefits the spin-oriented electronic transport and resultantly promotes the OER. This method paves the way for the construction of spin pathways in catalysts.

6 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper , the authors clarified the significance of regulating spin state of the active centers of transition metal oxides and discussed several characterization technologies for spin state and some recent strategies to regulate the spin state.
Abstract: Developing efficient and stable transition metal oxides catalysts for energy conversion processes such as oxygen evolution reaction and oxygen reduction reaction is one of the key measures to solve the problem of energy shortage. The spin state of transition metal oxides is strongly correlated with their catalytic activities. In an octahedral structure of transition metal oxides, the spin state of active centers could be regulated by adjusting the splitting energy and the electron pairing energy. Regulating spin state of active centers could directly modulate the d orbitals occupancy, which influence the strength of metal-ligand bonds and the adsorption behavior of the intermediates. In this review, we clarified the significance of regulating spin state of the active centers. Subsequently, we discussed several characterization technologies for spin state and some recent strategies to regulate the spin state of the active centers. Finally, we put forward some views on the future research direction of this vital field.

6 citations

Journal ArticleDOI
26 Dec 2022
TL;DR: In this article , Ru-Co spinel oxides with abundant cobalt vacancies (VCo-RCO) are successfully developed as a highly efficient electrocatalyst for OER.
Abstract: As is well known that the oxygen evolution reaction (OER) is dominant to determine water splitting, regulating the electronic structure of the electrocatalyst has been demonstrated to be an effective strategy for improving OER activity. Herein, Ru–Co spinel oxides with abundant cobalt vacancies (VCo-RCO) are successfully developed as a highly efficient electrocatalyst for OER. Interestingly, the introduction of Ru can induce the formation of cobalt vacancies, which can modulate the electronic state of VCo-RCO, optimizing the location of the d-band center and generating neighboring Ru–Co synergies, thereby improving the OER catalytic activity. As a result, the VCo-RCO exhibits a small overpotential of 240 mV at 10 mA/cm2, which is more advanced than that of Co3O4, RCO without defect, and various RuO2 catalysts. The in situ Raman analysis and density functional theory calculations further confirm the neighboring Ru–Co synergies of VCo-RCO, and this mechanism can not only facilitate fast electron transfer between Ru and Co sites through the bridging OOH but also reduce the adsorption strength of OER intermediates, leading to a significant enhancement of OER catalytic activity.

1 citations

Journal ArticleDOI
TL;DR: In this article , the authors clarified the significance of regulating spin state of the active centers of transition metal oxides and discussed several characterization technologies for spin state and some recent strategies to regulate the spin state.
Abstract: Developing efficient and stable transition metal oxides catalysts for energy conversion processes such as oxygen evolution reaction and oxygen reduction reaction is one of the key measures to solve the problem of energy shortage. The spin state of transition metal oxides is strongly correlated with their catalytic activities. In an octahedral structure of transition metal oxides, the spin state of active centers could be regulated by adjusting the splitting energy and the electron pairing energy. Regulating spin state of active centers could directly modulate the d orbitals occupancy, which influence the strength of metal-ligand bonds and the adsorption behavior of the intermediates. In this review, we clarified the significance of regulating spin state of the active centers. Subsequently, we discussed several characterization technologies for spin state and some recent strategies to regulate the spin state of the active centers. Finally, we put forward some views on the future research direction of this vital field.

1 citations

Journal ArticleDOI
TL;DR: In this article , the authors present a survey of the state of the art in bioinformatics and biomedicine research, including the following papers: http://www.firstpage
Abstract: First Page