2026-10-14T18:53:10Z https://www.scidb.cn/oai

10.57760/sciencedb.02876 2022-09-29T17:44:54Z

2022-09-29 Boosting Electrical Response toward Trace Volatile Organic Compounds Molecules via Pulsed Temperature Modulation of Pt Anchored WO3 Chemiresistor doi:10.57760/sciencedb.02876 en Insufcient limit of detection (LoD) toward volatile organic compounds (VOCs) hinders the promising applications of metal oxide chemiresistors in emerging air quality monitoring and/or breath analysis. There is an inherent limitation of widely adopted strategies of creating sensitive chemiresistors then operating at the optimized temperature via a continuous heating (CH) mode. Herein, a strategy combining Pt single atoms anchoring (chemical sensitization) with pulsed temperature modulation (PTM, physical sensitization) is proposed. Apart from generating abundant surface asymmetric oxygen vacancy (Pt-VO-W) active sites at pulsed high temperature (HT) stage, inward diffusion of trace target VOCs across the sensing layer at pulsed low temperature stage (driven by PTM induced concentration gradient), can greatly enhance the charge interaction probability between the generated surface active species and the surrounding VOCs, and thus offers a novel avenue on addressing the bottleneck issue of low LoD by PTM. Triggered by HT of 300 °C, the responses of Pt anchored WO3 chemiresistor to 1 ppm trimethylamine (TMA) and xylene can be drastically boosted from 1.9 (CH) to 6541.5 (PTM) and 1.5 (CH) to 1001.1 (PTM), respectively. And ultralow theoretic LoD of 0.78 ppt (TMA) and 0.18 ppt (xylene) are successfully achieved, respectively. asymmetric oxygen vacancy defects; inward gas diffusion; oxide chemiresistors; pulsed temperature modulation; trace VOCs detection Tiantian Dai Zhi Yan Meng Li Yulei Han Zanhong Deng Shimao Wang Ruyang Wang Xiaohong Xu Lei Shi Wei Tong Jun Bao Zhenhua Qiao Liang Li Gang Meng PUBLIC https://creativecommons.org/licenses/by/4.0/ dataset http://www.doi.org/10.1002/smtd.202200728 Science Data Bank