摘要
与助催化剂形成异质结,通过调整活性位点的电子结构和电荷输运来提高Ni_(2)P的电催化活性是一种可行的方法。本文成功构建了一种高效的Cu_(3)P/Ni_(2)P异质结催化剂,其中Cu_(3)P本身仅作为助催化剂,通过调节Ni_(2)P的电子转移和表面重构来提高电催化活性。结果表明,在10 mA·cm^(-2)的电流密度下,Cu_(3)P/Ni_(2)P具有优异的析氧反应(OER)活性,过电位为213 mV。结合实验结果和理论计算可知,Cu_(3)P助催化剂可以有效调整Ni中心的电子结构,实现电荷重分布,降低反应能垒,从而显著提高OER催化活性。此外,Cu_(3)P助催化剂诱导的丰富的晶界和晶格畸变促进了表面重构,形成Ni5O(OH)9,为OER提供了有效的活性位点。本工作通过引入助催化剂构建了一种新型异质结电催化剂,为优化过渡金属磷化物的电催化性能提供了一条有效途径。
Owing to the increasingly serious environmental problems,there is an urgent need for clean energy with a high energy density and low carbon emissions.As such,electrocatalytic water decomposition has attracted significant interest as an efficient hydrogen production method.The electrolysis of water has two important half-reactions:the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER).Among these two reactions,OER is considered to be the crucial and rate-determining step due to its slower kinetic process and higher overpotential compared to HER.Although noble metal oxides such as IrO_(2)and RuO_(2)have excellent OER properties under alkaline conditions,their high cost and scarcity limit their commercial application.Therefore,it is of significant interest to develop alternative OER electrodes with excellent catalytic activity,extremely low overpotential,high durability,and low cost.Ni_(2)P has attracted interest as an electrocatalyst and has improved activity after combination with a cocatalyst.The improved activity is due to heterojunction formation changing the electronic structure and charge transport at the active site.To this end,a novel highly efficient Cu_(3)P/Ni_(2)P heterojunction catalyst has been successfully constructed,in which Cu_(3)P functions solely as a cocatalyst to enhance the electrocatalytic activity by regulating the electron transfer and surface reconstruction of Ni_(2)P.Consequently,Cu_(3)P/Ni_(2)P exhibits superior OER activity and has an ultra-low overpotential of 213 mV at a current density of 10 mAꞏcm^(-2)and a small Tafel slope of 62 mVꞏdec-1 in 1 mol·L-1 KOH.Additionally,this peculiar self-supporting electrode possesses excellent electrochemical stability and long-term durability at a current density of 10 mAꞏcm^(-2)in an alkaline medium.Through a combination of experimental results and theoretical calculations,it has been shown that the Cu_(3)P cocatalyst effectively tailors the electronic structure of the Ni center.This results in charge redistribution and a lower reaction energy barrier,thereby significantly improving the OER catalytic activity.In addition,the abundant grain boundaries and lattice distortions induced by the Cu_(3)P cocatalyst promote surface reconstruction to form Ni5O(OH)9,providing an efficient active site for OER.This work constructed a novel heterojunction electrocatalyst by introducing a cocatalyst,offering an avenue for the optimization of the electrocatalytic performance of transition metal phosphide.
作者
邢雅娟
薛辉
孙静
郭念坤
宋天山
孙佳雯
郝翊茹
王勤
Yajuan Xing;Hui Xue;Jing Sun;Niankun Guo;Tianshan Song;Jiawen Sun;Yi-Ru Hao;Qin Wang(College of Chemistry and Chemical Engineering,Inner Mongolia University,Hohhot 010021,China)
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2024年第3期31-32,共2页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(22269015)
内蒙古自治区自然科学基金(2021ZD11)资助项目。
关键词
磷化物
异质结
助催化剂
表面重构
析氧反应
Phosphide
Heterojunction
Cocatalyst
Surface reconstruction
Oxygen evolution reaction
作者简介
Corresponding authors:王勤.Emails:qinwang@imu.edu.cn(Q.W.);Corresponding authors:薛辉.Emails:hxue@imu.edu.cn(H.X.),Tel.:+86-471-4992210(Q.W.).
