Formation of nanograined Ag-Co3O4 core@shell structure to achieve enhanced xylene sensing characteristics

초록

Xylene (C8H10) is a volatile organic compound as well as a pollutant which needs to be detected for various demands and applications. Herein, we report a unique core@shell (C-S) structure with core noble metal particles to incorporate catalytic elemnts. A nanograined Ag-Co3O4 C-S structure was prepared using a chemical synthesis method. Systematic xylene sensing studies were undertaken to prove the excellence of nanograined C-S structure. Various characterization techniques were used to confirm the synthesis of desired products with the expected features. The pristine sensor offered the highest performance to xylene at 350 degrees C, whereas nanograined Ag-Co3O4 C-S structure gas sensor worked at a lower temperature namely 250 degrees C. In addition, the maximum response of the pristine sensor to 50 ppm-xylene was about 1.26, whereas that of the nanograined Ag-Co3O4 C-S structure gas sensor was 2.47. Moreover, the latter sensor showed higher selectivity to xylene than the former sensor. The improved xylene sensing characteristics of the nanograined Ag-Co3O4 C-S structure gas sensor were caused by its high surface area, formation of Ag-Co3O4 heterojunctions, and catalytic effects of Ag nanoparticles. This study demonstrates the potential of this new system for sensing of xylene.

키워드