Regulating photocatalytic overall water splitting of ferroelectric heterostructures by size effect  

作　　者：Zixing Ye Daifu Yu Ruian Zhang Fei Qin Yiran Sun Jie Huang Zhanqi Zhou He Tian Gaorong Han Zhaohui Ren Gang Liu 

机构地区：[1]State Key Laboratory of Silicon and Advanced Semiconductor Materials,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China [2]Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China [3]Center of Electron Microscopy,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China

出　　处：《Nano Research》2024年第9期8000-8006,共7页纳米研究（英文版）

基　　金：supported by the National Key R&D Program of China(No.2021YFA1500800);the National Natural Science Foundation of China(Nos.52425201,52272129,and 12125407);the Natural Science Foundation of Zhejiang Province,China(No.LR21E020004);the ShanxiZheda Institute of Advanced Materials and Chemical Engineering(No.2021SX-FR007);the Joint Funds of the National Natural Science Foundation of China(No.U21A2067).

摘　　要：In the past decade,ferroelectric materials have been intensively explored as promising photocatalysts.An intriguing ability of ferroelectrics is to directly sperate the photogenerated electrons and holes,which is believed to arise from a spontaneous polarization.Understanding how polarization affects the photocatalytic performance is vital to design high-efficiency photocatalysts.In this work,we report a size effect of ferroelectric polarization on regulating the photocatalytic overall water splitting of SrTiO_(3)/PbTiO_(3)nanoplate heterostructures for the first time.This was realized hydrothermally by controlling the thickness and thus spontaneous polarization strength of single-crystal and single-domain PbTiO_(3)nanoplates,which served as the substrate for selective heteroepitaxial growth of SrTiO_(3).An enhancement of 22 times in the photocatalytic overall water splitting performance of the heterostructures has been achieved when the average thickness of the nanoplate increases from 30 to 107 nm.A combined experimental investigation revealed that the incompletely compensated depolarization filed is the dominated driving force for the photogenerated carrier separation within heterostructures,and its increase with the thickness of the nanoplates accounts for the enhancement of photocatalytic activity.Moreover,the concentration of oxygen vacancies for negative polarization compensation has been found to grow as the thickness of the nanoplates increases,which promotes oxygen evolution reaction and reduces the stoichiometric ratio of H_(2)/O_(2).These findings may provide the opportunity to design and develop high-efficiency ferroelectric photocatalysts.

关 键 词：single-domain nanoplates size effect ferroelectric polarization screening photocatalytic overall water splitting 

分 类 号：O644.1[理学—物理化学]