Formaldehyde-sensing properties of LaFeO₃ particles synthesized by citrate sol–gel method

LaFeO₃ (LFO) particles were synthesized by citrate sol–gel method and characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and specific surface and pore size analysis instrument. To investigate the formaldehyde (HCHO)-sensing properties, the side-heating gas sensor based on LFO particles was fabricated. The LFO particle-based gas sensor presented high response and good selectivity to HCHO at an operating temperature of 100 °C. At the range of 1–50 ppm HCHO, the LFO particle-based gas sensor exhibits a nearly linear response, and the linear correlation coefficient is 0.99. The response time and recovery time are about 33 and 27 s, respectively. The results indicate that LFO particles synthesized by citrate sol–gel method have potential applications for fabricating high-performance and low power consumption HCHO gas sensor.