Rich defects and nanograins boosted formaldehyde sensing performance of mesoporous polycrystalline ZnO nanosheets  

作　　者：Le-Xi Zhang Ming-Mei Zhao Yan-Yan Yin Yue Xing Li-Jian Bie 

机构地区：[1]School of Materials Science and Engineering,Tianjin Key Laboratory for Photoelectric Materials and Devices,Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education),National Demonstration Center for Experimental Function Materials Education,Tianjin University of Technology,Tianjin 300384,China [2]Department of Environmental Science and Engineering,Nankai University Binhai College,Tianjin 300270,China

出　　处：《Rare Metals》2022年第7期2292-2304,共13页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 21601094, 21401139 and 71804123);Tianjin Municipal Education Commission (No. 2018KJ271)

摘　　要：Comprehensive consideration of structural and electronic sensitization is of significant importance for rational design and assembly of high-performance gas sensors based on metal oxides.In this work,hierarchically mesoporous ZnO nanosheets are synthesized via a hydrothermal method followed by calcination.Material characterization reveals polycrystalline feature of these ZnO nanosheets rich in mesopores and defects.Gas sensing performance of as-synthesized ZnO nanosheets was sys-tematically investigated,taking formaldehyde as probe molecules.Compared with commercial ZnO nanoparticles,ZnO nanosheets exhibited enhanced formaldehyde sensing properties,including lower operation temperature,higher sensitivity,faster response,and smaller detection limit.Notably,the response(S=227.4)of ZnO nanosheets to 200×10^(-6) formaldehyde is about 17 times larger than that of ZnO nanoparticles(S=13.5).Excluding effects of grain size and surface area,enhanced sensing properties,especially response value,are credited in large part to synergistic actions of surface defects,grain boundaries,as well as unique structural advantage of ZnO nanosheets.Furthermore,this work offers a guideline for boosting performance of metal oxide-based gas sensors via surface defect control and grain boundary construction.

关 键 词：performance POLYCRYSTALLINE GRAIN 

分 类 号：TQ132.41[化学工程—无机化工] TB383.1[一般工业技术—材料科学与工程] TP212[自动化与计算机技术—检测技术与自动化装置]