Over 12%efficient kesterite solar cell via back interface engineering  

作　　者：Yunhai Zhao Zixuan Yu Juguang Hu Zhuanghao Zheng Hongli Ma Kaiwen Sun Xiaojing Hao Guangxing Liang Ping Fan Xianghua Zhang Zhenghua Su 

机构地区：[1]Shenzhen Key Laboratory of Advanced Thin Films and Applications,Key Laboratory of Optoelectronic Devices and Systems,College of Physics and Optoelectronic Engineering,Shenzhen University,Shenzhen 518060,Guangdong,China [2]CNRS,ISCR(Institut des Sciences Chimiques de Rennes)UMR 6226,Univ Rennes,Rennes F-35000,France [3]School of Photovoltaic and Renewable Energy Engineering,UNSW Sydney,Sydney NSW 2052,Australia [4]Shenzhen University Institute of Microscale Optoelectronics,Shenzhen University,Shenzhen 518060,Guangdong,China

出　　处：《Journal of Energy Chemistry》2022年第12期321-329,I0008,共10页能源化学（英文版）

基　　金：supported by the National Key R&D Program of China(no.2018YFE0203400);the National Natural Science Foundation of China(no.62074102);the Guangdong Basic and Applied Basic Research Foundation(no.2022A1515010979);the Science and Technology plan project of Shenzhen(nos.JCYJ20190808120001755 and 20220808165025003)。

摘　　要：Kesterite Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)has attracted considerable attention as a non-toxic and earthabundant solar cell material.During selenization of CZTSSe film at high temperature,the reaction between CZTSSe and Mo is one of the main reasons that result in unfavorable absorber and interface quality,which leads to large open circuit voltage deficit(VOC-def)and low fill factor(FF).Herein,a WO_(3)intermediate layer introduced at the back interface can effectually inhibit the unfavorable interface reaction between absorber and back electrode in the preliminary selenization progress;thus high-quality crystals are obtained.Through this back interface engineering,the traditional problems of phase segregation,voids in the absorber and over thick Mo(S,Se)_(2)at the back interface can be well solved,which greatly lessens the recombination in the bulk and at the interface.The increased minority carrier diffusion length,decreased barrier height at back interface contact and reduced deep acceptor defects give rise to systematic improvement in VOCand FF,finally a 12.66%conversion efficiency for CZTSSe solar cell has been achieved.This work provides a simple way to fabricate highly efficient solar cells and promotes a deeper understanding of the function of intermediate layer at back interface in kesterite-based solar cells.

关 键 词：Cu_(2)ZnSn(S Se)_(4) WO_(3)intermediate layer Crystal growth Minority carrier diffusion length Interface contact quality 

分 类 号：TB383.2[一般工业技术—材料科学与工程] TM914.4[电气工程—电力电子与电力传动]