Electroless plated SnO2–Pd–Au composite thin film for room temperature H2 detection

• DOI: 10.1016/j.electacta.2011.04.116
• Publication Date: 2011-05-10T03:58:42Z
• Authors: Xuguang Wen; Min Wang; Cen Wang; Jianzhong Jiang
• Keywords: Thermal Stability

Abstract Extremely thin SnO 2 nanosheets with high surface area were fabricated through a one-pot hydrothermal method. In this work, gas sensing property of the SnO 2 nanosheets was studied. SnO 2 –Pd–Au mixed thin films were prepared by electroless deposition of Pd, Au, and nanostructured SnO 2 onto the surface of a high resistance alumina substrate. The whole fabrication process was carried out at room temperature without any thermal treatment required. The films deposited on the alumina substrate were characterized by SEM and EDS. The co-deposited Au improved the electric conductance of the sensing film. A relatively large amount of Pd (Pd/Sn ratio around 1:1) was obtained for the film instead of the usually low doping value of Pd (∼0.1% level) for SnO 2 hydrogen sensor. It has been found that the SnO 2 –Pd–Au composite film sensor has fast response in the range of 134–1469 ppm toward hydrogen gas at room temperature. The sensor also shows good stability and repeatability. Effects of annealing condition of the sensing film on H 2 gas sensing performance was investigated as well. A possible machnism for SnO 2 –Pd room temperature hydrogen sensing is proposed.