Ultrasensitive gas sensor based on Pd/SnS2/SnO2 nanocomposites for rapid detection of H2

Abstract

With the emergence of hydrogen economy worldwide and the increase of safety problems caused by the highly flammable and explosive characteristics of hydrogen (H2), it is urgent to develop the portable sensors that can sensitively and quickly detect H2 leaks. In this work, the H2 sensing characteristics of Pd/SnS2/SnO2 nanocomposites synthesized via hydrothermal route as well as impregnation route were systematically investigated for the first time. The influence of different SnS2 and Pd loading on the H2 sensing performances of SnO2 nanoparticles was revealed by varying the addition levels of thiourea and palladium chloride. The H2 sensing experimental results demonstrated that SnS2 and Pd modification can greatly enhance the sensing capabilities of SnO2, where 1.0 at% Pd/SnS2/SnO2 sensor exhibited high response (95) and rapid response/recovery time (1/9 s) to 500 ppm H2 at 300 ℃, thus outperforming the current reported sensing performances of SnO2-based H2 sensors. The superior sensing characteristics of Pd/SnS2/SnO2 were attributed to the simultaneous synergistic effect of the three components. This study will supply a rational strategy for designing high sensitive and rapid response H2 sensors.