Medium-entropy oxides are commonly employed as electrocatalysts for the oxygen evolution reaction(OER)in electrolysers aimed at producing sustainable hydrogen.However,their poor conductivity poses a significant obstac...Medium-entropy oxides are commonly employed as electrocatalysts for the oxygen evolution reaction(OER)in electrolysers aimed at producing sustainable hydrogen.However,their poor conductivity poses a significant obstacle to further enhancing their electrocatalytic activity.It is therefore imperative to develop stable and highly active non-precious metal electrocatalysts for the advancement of sustainable energy technologies.CeO_(2)is incorporated into the FeNiMnO_(4)medium-entropy spinel oxide system as an“electron pump”to facilitate electron transfer from FeNiMnO_(4)to CeO_(2).Benefiting from the heterogenous interface and medium-entropy system,the medium-entropy spinel oxide FeNiMnO_(4)/CeO_(2)heterojunction electrocatalyst exhibits exceptional activity and stability for the alkaline OER.It requires an overpotential of 241 mV to reach the benchmark current density of 10 mA cm^(−2)with a lower Tafel slope of 44.8 mV dec^(−1).Theoretical calculations indicate that the incorporation of CeO_(2)effectively lowers the barriers for the potential-determining steps in the OER,and optimizes the electronic structure to facilitate the OER process.The present study demonstrates that constructing medium-entropy heterojunction materials represents a crucial approach towards developing efficient and durable OER electrocatalysts.展开更多
基金supported by the Key Research and Development Program of Jiangsu Provincial Department of Science and Technology of China(BE2022605)the Fundamental Research Funds for the Central Universities(14380163).
文摘Medium-entropy oxides are commonly employed as electrocatalysts for the oxygen evolution reaction(OER)in electrolysers aimed at producing sustainable hydrogen.However,their poor conductivity poses a significant obstacle to further enhancing their electrocatalytic activity.It is therefore imperative to develop stable and highly active non-precious metal electrocatalysts for the advancement of sustainable energy technologies.CeO_(2)is incorporated into the FeNiMnO_(4)medium-entropy spinel oxide system as an“electron pump”to facilitate electron transfer from FeNiMnO_(4)to CeO_(2).Benefiting from the heterogenous interface and medium-entropy system,the medium-entropy spinel oxide FeNiMnO_(4)/CeO_(2)heterojunction electrocatalyst exhibits exceptional activity and stability for the alkaline OER.It requires an overpotential of 241 mV to reach the benchmark current density of 10 mA cm^(−2)with a lower Tafel slope of 44.8 mV dec^(−1).Theoretical calculations indicate that the incorporation of CeO_(2)effectively lowers the barriers for the potential-determining steps in the OER,and optimizes the electronic structure to facilitate the OER process.The present study demonstrates that constructing medium-entropy heterojunction materials represents a crucial approach towards developing efficient and durable OER electrocatalysts.
