Enhancing DMC sensing performance of perovskite LaFeO3 via oxygen vacancies modulation by A-site Sr doping

The safety issues caused by the leakage of lithium-ion batteries (LIBs) electrolyte have attracted growing attention. Due to the volatile, flammable, and explosive nature, even minor electrolyte leakage can lead to serious safety risks. Real-time detection of dimethyl carbonate (DMC), a primary electrolyte component, is essential for preventing LIB-related accidents. This study presents a gas sensor based on Sr-doped LaFeO 3 hollow microspheres for DMC detection. Sr doping introduces additional oxygen vacancies, leading to a significant enhancement in sensor performance. The LaFeO 3 -Sr-5 sensor with a Sr doping concentration of 5 at% exhibited the best performance, including a high response value (∼53.9–1 ppm DMC), excellent sensitivity (obvious response to 10 ppb DMC), outstanding selectivity, and good stability at an operating temperature of 110℃. Density functional theory (DFT) calculations confirmed that the adsorption capacity of DMC on the surface of LaFeO 3 material was significantly increased after Sr 2 + doping. In simulated LIB electrolyte leakage scenarios, the sensor shows rapid and distinct responses, demonstrating its potential for practical application in battery safety monitoring.