Facile lotus-leaf-templated synthesis and enhanced xylene gas sensing properties of Ag-LaFeO3 nanoparticles

Abstract

For developing highly sensitive, selective and stable gas sensing materials for the detection of volatile organic compounds, we report porous micro/nano-level structure Ag-LaFeO₃ nanoparticles which have been successfully synthesized using a lotus leaf as a bio-template via a sol–gel process. Combined with the molecular imprinting technique, the selectivity of the gas sensor can be altered and enhanced gas-sensing properties are obtained due to the unique molecular recognition and large specific surface area. The Ag-LaFeO₃ nanoparticles are found to exhibit an ultrahigh xylene response (R_g/R_a = 16.76 to 10 ppm), fast gas response and recovery (68 and 36 s) and superior selectivity against the other tested interfering gases at a relatively low operating temperature of 125 °C. They also exhibit excellent humidity stability and long-term stability with small deviations, and this result may deliver a new approach that enables the stable detection of xylene gas.