Room temperature LPG sensing of highly responsive Ag-doped CuO: SnO2 nanocomposite film

Abstract

The designed nanocomposite film of self-assembled 2D Ag-doped CuO:SnO₂ nanoflakes have been successfully synthesized through facile one-step hydrothermal technique. The fabricated sensor film is developed to detect liquefied petroleum gas (LPG) at room temperature. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and UV–visible spectroscopy comprehensively characterize the film's microstructure, morphology, element composition, and optical properties. The LPG sensing outcomes reveal that the Ag-doped CuO:SnO₂ film based sensor exhibits exceptional response and excellent repeatability towards LPG at room temperature. This is predominantly due to formation of CuO: SnO₂ interface, sensitized by doping silver (Ag) that drastically increases the carrier concentration of the NC sensor film and provides superior ability to detect LPG across a range of concentrations at room temperature. The sensor response increases from 300 % for 0.5 vol% LPG to a maximum of 414 % at 2.0 vol%. Notably, the sensor demonstrates fast response and recovery times (21 s and 30 s for 0.5 vol% LPG). These promising attributes position the NC sensor film as a strong candidate for real-world LPG sensing applications. Additionally, the research proposes a comprehensive mechanism explaining the NC sensor film's detection performance.