Fast response-recovery time toward acetone by a sensor prepared with Pd doped WO3 nanosheets

Ke He; Zhao Jin; Xiangfeng Chu; Wenjie Bi; Wu Wang; Chao Wang; Shantang Liu

doi:10.1039/c9ra04429a

Fast response-recovery time toward acetone by a sensor prepared with Pd doped WO₃ nanosheets

RSC Adv. 2019 Sep 10;9(49):28439-28450. doi: 10.1039/c9ra04429a. eCollection 2019 Sep 9.

Authors

Ke He¹, Zhao Jin¹, Xiangfeng Chu², Wenjie Bi¹, Wu Wang¹, Chao Wang¹, Shantang Liu¹

Affiliations

¹ Key Laboratory for Green Chemical Process of Ministry of Education, School of Chemistry and Environmental Engineering, Wuhan Institute of Technology Xiongchu Avenue Wuhan 430073 China stliu@wit.edu.cn.
² School of Chemistry and Chemical Engineering, Anhui University of Technology Maanshan 243002 Anhui P. R. China.

Abstract

Pd-WO₃ nanosheets were synthesized through a one-step hydrothermal method using Na₂PdCl₄ solution as the palladium source and sodium tungstate as the tungsten source, and were used to detect acetone. After being characterized by TEM, XRD, BET and XPS, it was found that Pd doped on the surface of WO₃ nanosheets was mainly present as metal palladium, and the specific surface area increased after doping. In addition, the effect of Pd doping on gas sensing properties was studied. When the Pd-doped amount was 2 at%, sensors fabricated with the composites had the best gas sensing performance. Under a 100 ppm acetone atmosphere, the response time was 1 s and the recovery time was 9 s. The detection limit for acetone was 50 ppb at the optimum working temperature of 300 °C, and the selectivity for acetone was excellent under 100 ppm atmosphere (S _acetone/S _ethanol = 5.06). The excellent gas sensing properties of this material are mainly attributed to the high catalytic activity and the catalytic spill-over effect of the Pd nanoparticles, which provided additional active sites for the sensitive materials.