A low temperature nano-structured SrTiO3 thick film oxygen gas sensor

A low temperature nano-structured Strontium Titanate (SrTiO3) thick film oxygen gas sensors were obtained by high-energy ball milling technique and thick-film screen-printing technique. SrTiO3 nano-sized powders of around 20 nm were produced from commercial SrTiO3 and synthesized SrTiO3. The material micro-structural properties and sensor oxygen sensing properties were characterized using X-ray diffraction (XRD) and gas sensing measurements respectively. Experimental results show that the sensing property of the synthesized SrTiO3 sensors with an annealing temperature of 400 °C is much better than the commercial SrTiO3 sensors (both milled and not milled materials). Especially, their optimal operating temperature of around 40 °C is the lowest reported value for such metal oxide semiconductor gas sensors ever achieved.