Humidity-independent highly selective H₂S sensor based on ruthenium doped In₂O₃ synthesized using bio-template method

Highly selective hydrogen sulfide sensor based on 3 wt% Ruthenium doped In₂O₃ obtained by biotemplate synthesis was fabricated. For this, purified cellulose was impregnated with a solution containing Indium acetate In(CH₃COO)₃ and Ruthenium acetylacetonate Ru(C₅H₇O₂)₃, dried and calcined at 600 ^оС. Nanomaterial obtained using this method consists of sintered 15 - 20 nm grains. The limit of Н₂S detection of the sensor is much below 100 ppb. The sensor characteristics of the sensor were determined both at stationary temperature and at the pulse heating of the sensor from 100 to 450 ^оС with 15 s period. Sensor response to 10 ppm of Н₂S at 150 ^оС is equal to 52, while the response in the pulsing heating regime exceeds the value of 185. The selectivity coefficient of the sensor with respect to carbon monoxide, hydrogen and ammonia gas at 150 ^оС is of about 100, this coefficient increases up to ∼1000, when temperature modulation is used for sensor operation. The response of the sensor doesn't decrease in humid atmosphere.