Ag-SnO2 nanofibers with lattice oxygen activation for high performance triethylamine gas sensor

Ag-loaded SnO 2 nanofibers were successfully fabricated via electrospinning combined with an in situ reduction strategy. • The Ag loading activates the lattice oxygen in SnO 2 , enabling it to participate in the gas sensing process. • The response value of SnO 2 with 2 mol% Ag to 100 ppm is 79 times that of pure SnO 2 . • The enhanced sensing mechanism is systematically elucidated through XPS, EPR, and DFT calculations. TEA is a highly flammable and neurotoxic volatile organic compound; prolonged exposure can lead to emphysema and even immediate death, making the development of rapid, highly responsive TEA gas sensors an urgent priority. Although tin dioxide (SnO 2 )-based sensors have been extensively studied, they suffer from low sensitivity and high operating temperatures. In this study, silver-loaded tin dioxide nanofibers (Ag-SnO 2 NFs) with a porous hollow structure were fabricated using electrospinning combined with in-situ reduction technology. The Schottky junction at the Ag-SnO 2 interface triggers interfacial electron redistribution, thereby activating lattice oxygen (O L ) in SnO 2 and converting it into adsorbed oxygen species, which enhances the gas-sensing performance for TEA. At 200℃, the AS-2 sensor exhibited a response value of 2163.6 for 100 ppm of TEA, which is 79 times that of pure SnO 2 , and demonstrated fast response and recovery times (48 s/44 s). In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density functional theory (DFT) calculations further elucidated this mechanism. This study provides a new mechanistic insight into how noble metal modification activates lattice oxygen and converts it into adsorbed oxygen to enhance gas sensing performance, offering rational design principles for advanced gas sensors targeting harmful volatile compounds. Download: Download high-res image (151KB) Download: Download full-size image