Bi-doping induced oxygen vacancy engineering in LaFeO₃ porous nanospheres for low-temperature and highly selective...

Bi-doped LaFeO₃ porous microspheres with competitive gas-sensing performance toward n-butanol were successfully synthesized through a simple glutamic acid-assisted solvothermal method. This approach effectively regulated the oxygen-vacancy concentration in the material. Comprehensive characterization confirmed that Bi³⁺ was successfully incorporated into the LaFeO₃ lattice, promoting partial Fe³⁺/Fe⁴⁺ conversion and generating abundant oxygen vacancies. Based on the optimized La_0.94Bi_0.06FeO₃ sensor, the optimal operating temperature was significantly reduced to 150 ℃. At this temperature, the response to 10 ppm n-butanol reached 21, approximately seven times higher than that of pristine LaFeO₃, with a detection limit as low as 101 ppb. Furthermore, the sensor demonstrated competitive selectivity, long-term stability, and humidity resistance. The improved sensing performance is likely associated with several factors, including oxygen vacancies, surface electronic modulation, and porous structure. This work presents an effective strategy for developing gas sensors based on high-performance perovskites by way of A cation doping.