Study of collective efforts of catalytic activity and photoactivation to enhance room temperature response of SnO2 thin film sensor for methane

Room temperature response characteristics of SnO2 thin film sensors loaded with palladium catalyst clusters of varying thickness are investigated for methane under the exposure of ultraviolet radiation. The SnO2-Pd cluster sensor structures have been prepared using rf sputtering. Combined effect of UV radiation exposure (lambda =365 nm) and presence of Pd catalyst clusters (10 nm thick) on SnO2 thin film sensor surface is seen to lead to an enhanced sensing response (S= (R-a - R-g)R-g =252.3) for the detection of methane (200 ppm) at room temperature which is higher to that obtained (S = (R-a - R-g)/R-g = 158) without UV illumination at elevated temperature of 220 degrees C. The present study therefore investigates the twin effect of UV illumination and the catalytic activity of palladium clusters on methane sensing characteristics of SnO2 thin film sensors. Obtained results are encouraging for commercial realization of room temperature SnO2 based thin film sensor for methane gas with enhanced response. (C) 2013 Elsevier B.V. All rights reserved.