Comparison of Pd, Pt and Pt/Pd as Catalysts for Hydrogen Sensor Films

Hydrogen has been attracting much interest recently as a source of clean and sustainable energy. However, the volatility of hydrogen, its tendency to explode at concentrations as low as 4 %2in air, requires a reliable sensing technology for safe hydrogen utilization. An optical hydrogen safety sensor based on gasochromic thin films can detect a change in color of the film upon exposure to hydrogen gas in an area where a hydrogen leak is suspected. In this study, we compared the sensitivity and the durability of hydrogen sensor films of Pd/WO(3), Pt/WO(3), and Pt/Pd/WO(3). The change in the optical transmittance of the films was measured as these films were repeatedly exposed to hydrogen and air.