Single Pt atom-based gas sensor: Break the detection limit and selectivity of acetone

Abstract

To improve gas sensing performance of oxide semiconductor is a collective goal of science community, due to that gas sensor is a class of pivotal component of environmental monitoring, the Internet of things and medical equipment. We introduced isolated single platinum atoms on the defective WO3−x nanosheets (SA-Pt/WO3−x), and investigated the status of single atoms by XPS, HAADF-STEM and in situ FT-IR and so forth. The SA-Pt/WO3−x based sensor exhibits high response level (Ra/Rg=43.4 to 5 ppm), exceptional ultrahigh selectivity (Sbest/Ssecond=2.8) and ultimate detection limit (Ra/Rg=4.3 to 0.1 ppm) in acetone gas sensing. In addition, the counterparts of WO3 and Pt nanoparticles were utilized as comparison to investigate the synthesis and gas sensing mechanism thoroughly. This work illustrates the research to fit the needs of ultralow concentration gas sensor application.