C9N4 as excellent dual electrocatalyst:A first principles study  

作　　者：Wei Xu WenWu Xu Xiangmei Duan 许伟;许文武;段香梅(School of Physical Science and Technology,Ningbo University,Ningbo 315211,China;Laboratory of Clean Energy Storage and Conversion,Ningbo University,Ningbo 315211,China)

机构地区：[1]School of Physical Science and Technology,Ningbo University,Ningbo 315211,China [2]Laboratory of Clean Energy Storage and Conversion,Ningbo University,Ningbo 315211,China

出　　处：《Chinese Physics B》2021年第9期424-428,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 11574167 and 11874033);the K C Wong Magna Foundation in Ningbo University

摘　　要：We perform first principles calculations to investigate the catalytic behavior of C_(9)N_(4)nanosheet for water splitting.For the pristine C_(9)N_(4),we find that,at different hydrogen coverages,two H atoms adsorbed on the 12-membered ring and one H atom adsorbed on the 9-membered ring show excellent performance of hydrogen evolution reaction(HER).Tensile strain could improve the catalytic ability of C_(9)N_(4)and strain can be practically introduced by building C_(9)N_(4)/BiN,and C_(9)N_(4)/GaAs heterojunctions.We demonstrate that the HER performance of heterojunctions is indeed improved compared with that of C_(9)N_(4)nanosheet.Anchoring transition metal atoms on C_(9)N_(4)is another strategy to apply strain.It shows that Rh@C_(9)N_(4)exhibits superior HER property with very low Gibbs free energy change of-30 meV.Under tensile strain within~2%,Rh@C_(9)N_(4)could catalyze HER readily.Moreover,the catalyst Rh@C_(9)N_(4)works well for oxygen evolution reaction(OER)with an overpotential of 0.58 V.Our results suggest that Rh@C_(9)N_(4)is favorable for both HER and OER because of its metallic conductivity,close-zero Gibbs free energy change,and low oneset overpotential.The outstanding performance of C_(9)N_(4)nanosheet could be attributed to the tunable porous structure and electronic structure compatibility.

关 键 词：C_(9)N_(4)nanosheets dual electrocatalyst hydrogen evolution reaction oxygen evolution reaction 

分 类 号：TQ116.21[化学工程—无机化工] TQ426