Gas sensors for sustainable and safe integrated gasification-FC system

Abstract Sustainability, safety and optimization of gasification systems for hydrogen production are strictly correlated to efficient monitoring devices and chemical gas sensors based on perovskite materials represent a very attractive technology for this purpose. The aim of this work is to evaluate sensing performances of LaFeO 3 based materials for the application in integrated gasification-FC systems and their possible enhancements thanks to titanium partial substitution. Two perovskites, LaTi 0.4 Fe 0.6 O 3 and LaFeO 3 , were therefore prepared via auto-combustion synthesis and tested in a bench scale reactor for CO, H 2 and H 2 S exposures. Synthesis parameters were properly defined and set to Φ = 0.45, CA/M = 2.5 and pH = 7. Transition of conductive behaviour (from p- to n-type) was observed. Titanium partial substitution provided higher sensitivity to CO at higher temperatures. Sensitivity to H 2 was greater for unsubstituted material, but titanium presence assured chemical and thermal stability. During H 2 S tests, instead, irreversible reaction with materials occurred compromising sensing performances.