Characterization of WO3/Silicone Rubber Composites for Hydrogen-Sensitive Gasochromic Application

WO₃ and silicone rubber (SR)-based gasochromic composites were fabricated to detect hydrogen leaks at room temperature. WO₃ rod-like nanostructures were uniformly distributed in the SR matrix, with a particle size of 60-100 nm. The hydrogen permeability of these composites reached 1.77 cm³·cm/cm²·s·cm_Hg. At a 10% hydrogen concentration, the visible light reflectance of the composite decreased 49% during about 40 s, with a color change rate of 6.4% s^-1. Moreover, the composite detected hydrogen concentrations as low as 0.1%. And a color scale was obtained for easily assessing hydrogen concentrations in the environment based on the color of composites. Finally, the composite materials as disposable sensors underwent testing at several Sinopec hydrogen refueling stations.