Ag-Modified Porous Perovskite-Type LaFeO₃ for Efficient Ethanol Detection

Abstract

Perovskite (ABO3) nanosheets with a high carrier mobility have been regarded as the best candidates for gas-sensitive materials arising from their exceptional crystal structure and physical–chemical properties that often exhibit good gas reactivity and stability. Herein, Ag in situ modified porous LaFeO3 nanosheets were synthesized by the simple and efficient graphene oxide (GO)-assisted co-precipitation method which was used for sensitive and selective ethanol detection. The Ag modification ratio was studied, and the best performance was obtained with 5% Ag modification. The Ag/LaFeO3 nanomaterials with high surface areas achieved a sensing response value (Rg/Ra) of 20.9 to 20 ppm ethanol at 180 °C with relatively fast response/recovery times (26/27 s). In addition, they showed significantly high selectivity for ethanol but only a slight response to other interfering gases. The enhanced gas-sensing performance was attributed to the combination of well-designed porous nanomaterials with noble metal sensitization. The new approach is provided for this strategy for the potential application of more P-type ABO3 perovskite-based gas-sensitive devices.

Keywords

• perovskite
• Ag/LaFeO₃
• ethanol sensing
• gas sensor