Hydrogen energy is an important energy carrier,which is an ideal choice to meet energy demand and reduce harmful gas emissions.The green recycling of hydrogen energy depends on water electrolysis and hydrogen fuel cel...Hydrogen energy is an important energy carrier,which is an ideal choice to meet energy demand and reduce harmful gas emissions.The green recycling of hydrogen energy depends on water electrolysis and hydrogen fuel cells,which involves hydrogen oxidation reaction(HOR)and hydrogen evolution reaction(HER).The activity of HER/HOR in alkaline electrolyte,however,exhibits a significantly lower magnitude(2–3 orders)compared to that observed in an acidic medium,which hinders the development of alkaline water electrolysis and alkaline membrane fuel cells.Therefore,comprehending the characteristics of HOR/HER activity in alkaline electrolytes and elucidating its underlyingmechanismis a prerequisite for the designof advanced electrocatalysts.Based on this background,this reviewwill briefly summarize the explanations and controversies about the basic HOR mechanism,including bifunctional mechanismand hydrogen binding energy theory.Moreover,the crucial affecting factors of theHOR kinetics,such as dband center theory,interfacial water recombination,alkali metal cations and electronic effects,are discussed.Thus,based on the above theories,the design principle,catalytic performance,and latest progress ofHOR electrocatalysts are summarized.An outlook and future research perspectives of advanced catalysts for hydrogen energy recycling are addressed.This reviewis helpful to understand the latest development ofHORmechanismand design cost-effective and high-performance HOR electrocatalysts towards the production of clean renewable energies.展开更多
基金supported by the National Natural Science Foundation of China(22234005 and 21974070)the Natural Science Foundation of Jiangsu Province(BK20222015)Young Academic Leaders of the Qing Lan Project of Jiangsu Province(SUJIAOSHIHAN[2022]No.29).
文摘Hydrogen energy is an important energy carrier,which is an ideal choice to meet energy demand and reduce harmful gas emissions.The green recycling of hydrogen energy depends on water electrolysis and hydrogen fuel cells,which involves hydrogen oxidation reaction(HOR)and hydrogen evolution reaction(HER).The activity of HER/HOR in alkaline electrolyte,however,exhibits a significantly lower magnitude(2–3 orders)compared to that observed in an acidic medium,which hinders the development of alkaline water electrolysis and alkaline membrane fuel cells.Therefore,comprehending the characteristics of HOR/HER activity in alkaline electrolytes and elucidating its underlyingmechanismis a prerequisite for the designof advanced electrocatalysts.Based on this background,this reviewwill briefly summarize the explanations and controversies about the basic HOR mechanism,including bifunctional mechanismand hydrogen binding energy theory.Moreover,the crucial affecting factors of theHOR kinetics,such as dband center theory,interfacial water recombination,alkali metal cations and electronic effects,are discussed.Thus,based on the above theories,the design principle,catalytic performance,and latest progress ofHOR electrocatalysts are summarized.An outlook and future research perspectives of advanced catalysts for hydrogen energy recycling are addressed.This reviewis helpful to understand the latest development ofHORmechanismand design cost-effective and high-performance HOR electrocatalysts towards the production of clean renewable energies.
