Promoting effect of interfacial hole accumulation on photoelectrochemicalwater oxidation in BiVO_(4) and Mo-doped BiVO_(4)  

作　　者：Xiaofeng Wu Freddy E.Oropeza Shixin Chang Marcus Einert Qingyang Wu Clément Maheu Julia Gallenberger Chuanmu Tian Kangle Lv Jan P.Hofmann 

机构地区：[1]Surface Science Laboratory,Department of Materials-and Geosciences,Technical University of Darmstadt,Peter-Grünberg-Straße 4,64287,Darmstadt,Germany [2]Photoactivated Processes Unit,IMDEA Energy Institute,Parque Tecnológico de Móstoles,Avda.Ramón de La Sagra 3,28935,Móstoles,Madrid,Spain [3]Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education,College of Resources and Environment,South-Central Minzu University,Wuhan,430074,China [4]Nantes Université,CNRS,Institut des Matériaux Jean Rouxel,IMN,F-44000,Nantes,France

出　　处：《Advanced Powder Materials》2024年第6期26-32,共7页先进粉体材料(英文)

基　　金：support of the China Scholarship Council,affiliated to the Ministry of Education of the P.R.of China(Scholarships no.201708420159,202208320036 and 202008420222);JG and JPH acknowledge financial support from the German Ministry of Education and Research BMBF under project 03HY105H;Dr.Marcus Einert and Dr.Clément Maheu acknowledge funding from the German Research Foundation(DFG)under projects 469377211 and 423746744,respectively。

摘　　要：Hole transfer at the semiconductor-electrolyte interface is a key elementary process in(photo)electrochemical(PEC)water oxidation.However,up to now,a detailed understanding of the hole transfer and the influence of surface hole density on PEC water oxidation kinetics is lacking.In this work,we propose a model for the first time in which the surface accumulated hole density in BiVO_(4)and Mo-doped BiVO_(4)samples during water oxidation can be acquired via employing illumination-dependent Mott-Schottky measurements.Based on this model,some results are demonstrated as below:(1)Although the surface hole density increases when increasing light intensity and applied potential,the hole transfer rate remains linearly proportional to surface hole density on a log-log scale.(2)Both water oxidation on BiVO_(4)and Mo-doped BiVO_(4)follow first-order reaction kinetics at low surface hole densities,which is in good agreement with literature.(3)We find that water oxidation active sites in both BiVO_(4)and Mo-doped BiVO_(4)are very likely to be Bi^(5+),which are produced by photoexcited or/and electroinduced surface holes,rather than VO_(x)species or Mo^(6+)due to their insufficient redox potential for water oxidation.(4)Introduction of Mo doping brings about higher OER activity of BiVO_(4),as it suppresses the recombination rate of surface holes and increases formation of Bi^(5+).This surface hole model offers a general approach for the quantification of surface hole density in the field of semiconductor photoelectrocatalysis.

关 键 词：Water splitting Bismuth vanadate Rate law analysis Surface holes PHOTOELECTROCHEMISTRY 

分 类 号：O61[理学—无机化学]