Abstract
Gas sensors fabricated by metal oxide semiconductors (SMOs) exhibited promising prospect for acetone detection due to their high sensitivity, small sizes, simple operation, facile fabrication and low cost. However, the current SMOs still face diverse challenges involving high power consumption, low response, poor anti-interfering ability and weak repeatability. In this work, in order to meet the ever-increasing requirements for acetone detection, Pt nanoparticles (NPs) were embedded into ZIF-8 templates then loaded on porous SnO2 nanofibers (NFs) via electrospinning and subsequent annealing process with a control of heating rate. The gas sensing characteristics of pristine SnO2, SnO2-ZnO, and Pt-ZnO-SnO2 porous NFs were investigated. The Pt-ZnO-SnO2 porous NFs displayed an ultrahigh response (R-a/R-g = 104.26-100 ppm at 170 degrees C), high selectivity and low detection limit (200 ppb) to acetone during dynamic measurements. In this study, the advanced sensing behavior can be ascribed to the multi-heterojunctions construction at the interface of SnO2-ZnO, ZnO/PtO2 and SnO2/PtO2, the increasement of oxygen vacancies, as well as the electronic and chemical sensitization of Pt NPs. The well-dispersed and ultrasmall-sized Pt NPs (similar to 3 nm) functionalized on porous SnO2 NFs also play an essential role in fabricating high-performance acetone sensors. (C) 2021 Elsevier B.V. All rights reserved.
NSTL
Elsevier