A-site deficiency and Mn doping synergistically tailored LaFeO3 for high-performance H2S sensor

The detection of H 2 S, a highly toxic and corrosive gas prevalent in industrial processes, is imperative for safety and environmental monitoring. This necessitates the development of sensors exhibiting excellent sensitivity, quick response/recovery time, and superior selectivity. In this work, hollow and porous nanowires were fabricated via an ultrasound-assisted electrospinning method. By synergistically combining A-site deficiency engineering and B-site doping, a sensing material with high specific surface area and increased surface-adsorbed oxygen was achieved at a Mn doping level of 0.2. Operating at 130 °C, the gas-sensing material displays a high response of 113.5 toward 100 ppm H 2 S, approximately 15 times greater than that of pure LaFeO 3 along with rapid response/recovery time, respectively. The sensor also exhibits outstanding repeatability, selectivity, long-term stability, and humidity resistance. Moreover, it maintains remarkable sensing performance even at temperatures as high as 500 °C, indicating its potential for applications across a broad temperature range. Combined with theoretical calculations and experimental studies, the superior gas-sensing properties originate primarily from the synergistic effect between the nonstoichiometric behavior induced by A-site defects and the lattice distortion along with the increased active sites resulting from B-site doping. These findings pave the way for developing high-performance H 2 S sensing materials.