Photo induced NO2 sensing properties of bismuth triiodide (BiI3) nanoplates at room temperature

Herein we report on the growth of layered BiI3 nanoplates materials and their sensing properties of NO2 under violet light illumination. The BiI3 nanoplates were grown on a glass substrate using a chemical vapor deposition (CVD) system, with an average thickness of 30 nm and the lateral dimension of 150-170 nm. Their photo-induced sensing response for 20 ppm NO2 and the response/recovery time are approximately similar to 11.2% and 18/36 s, respectively. The limit of detection (LOD) of NO2 for the BiI3 sensor is 25 ppb. A possible light-induced gas-sensing mechanism was proposed and investigated for the BiI3 nanoplate. (C) 2019 Published by Elsevier Ltd on behalf of Acta Materialia Inc.