Unusual effects of vacuum annealing on large-area Ag_(3)PO_(4) microcrystalline film photoanode boosting cocatalyst-and scavengerfree water splitting  

作　　者：Qi Cao Jun Yu Yue Cao Jean-Jacques Delaunay Renchao Che 

机构地区：[1]Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,School of Energy and Environment,Southeast University,Nanjing,210096,China [2]Department of Mechanical Engineering,School of Engineering,The University of Tokyo,Tokyo,113-8656,Japan [3]Laboratory of Advanced Materials,Department of Materials Science,And Collaborative Innovation Center of Chemistry for Energy Materials(iChEM),Fudan University,Shanghai,200438,China [4]Guangdong Provincial Key Laboratory of Nano-Micro Materials Research,School of Chemical Biology and Biotechnology,Peking University Shenzhen Graduate School,Shenzhen,518055,China [5]Department of Chemistry,School of Science,The University of Tokyo,Tokyo,113-8656,Japan

出　　处：《Journal of Materiomics》2021年第5期929-939,共11页无机材料学学报（英文）

基　　金：This work was supported by Fundamental Research Funds for the Central Universities of Ministry of Education of China(Southeast University);Core-to-Core Program(Advanced Research Networks Type A)of Japan Society for the Promotion of Science(JSPS);Q.Cao acknowledges the support of China Scholarship Council(No.201506100018);the START project of Japan Science and Technology Agency(JST);R.Che thanks the support of National Basic Research Program(973 Program No.2018YFA0209102);National Science Fund for Distinguished Young Scholars(No.51725101);National Natural Science Foundation of China(Nos.11727807,51672050,and 61790581)of China.

摘　　要：Ag_(3)PO_(4) as a novel photoanode material,despite its arguably highest photoactivity,suffers for its poor light absorption and stability for photoelectrochemical(PEC)water oxidation.In this work,4.54.5 cm^(2) Ag_(3)PO_(4) microcrystalline films are grown via a room-temperature solution process,and vacuum annealing is proposed to solve the stability and light absorption issues.It is found that the major process below 400℃ of vacuum annealing is the|Recovery|process for Ag_(3)PO_(4) microcrystals,when lattice defects and Ag0 surface species get reduced.Next,|Recrystallization|stage occurs at>40℃.The recovery of native defects of silver vacancies,with both density functional theory calculation and experimental results,could simultaneously improve the light absorption and catalytic activity of Ag_(3)PO_(4).The 400℃-annealed Ag_(3)PO_(4) photoanode,with enhanced light harvesting and crystal quality,exhibits 88% increase in(Jlight-Jdark)value(1.94 mA cm^(-2))than non-annealed photoanode(1.03 mA cm^(-2)).Moreover,it retains>99% current density after a 4000-s stability test.These results suggest that vacuum annealing can substantially improve the PEC performance of Ag_(3)PO_(4) microcrystalline film photoanodes due to mitigated effects of native defects,improved light harvesting,and inhibited Ag_(3)PO_(4) decomposition during water oxidation reaction.

关 键 词：ORTHOPHOSPHATE Defect engineering Light harvesting Oxygen evolution reaction(OER) Hydrogen production POST-ANNEALING 

分 类 号：TQ116.2[化学工程—无机化工] TQ426