Promotional effect of nitric acid treatment on CO sensing properties of SnO2/MWCNT nanocomposites

In this paper, SnO2/MWCNT nanocomposites with different types of MWCNTs, namely as-received, acid treated and Ag-decorated, were synthesized via a facile method and their CO gas sensing properties were investigated. Microstructure and phase formation of the synthesized composites were studied using FE-SEM and XRD, respectively. Fourier transform infrared spectroscopy (FTIR) was employed to study the functional groups on the surface of MWCNTs after acid treatment. CO gas sensing results showed that the samples containing 0.8 wt.% MWCNT with 2 h acid treatment by HNO3 have the best response to CO gas.