A reusable and attachable hydrogen leak detector based on a nanoporous gasochromic Pd-WO3-Nafion film

A transparent nanoporous Pd-WO 3 -Nafion film is developed for gasochromic H 2 leak detection. • The Nafion overlayer significantly boosts the transmittance variation and response kinetics. • A semi-enclosed attachable H 2 leak detector with a top vent ensures the safe upward release of H 2 . • The reusable and detachable detector allows precise visual localization of leaks in H 2 systems. Hydrogen (H 2 ) is a promising clean energy carrier, but its high leakage risk and explosive nature demand safe and reliable detection technology. Here, we present a reusable and attachable H 2 leak detector based on a transparent gasochromic Pd-WO 3 -Nafion film. The film consists of a nanoporous WO 3 layer decorated with an ultrathin Pd (2 nm) catalyst and a Nafion overlayer. It exhibits a transmittance variation of approximately 59% (from 75% to 16%) upon exposure to 4% H 2 , with a coloring time of 69 s and a bleaching time of 117 s. Notably, the Nafion coating significantly enhances the transmittance variation and response kinetics compared to Nafion-free films. Building on this material, we design a semi-enclosed detector with a top vent for safe upward H 2 release and clear visual detection. Its detachable configuration enables repeated use and precise leak localization across complex systems, providing a cost-effective, visually intuitive solution for H 2 infrastructure. Download: Download high-res image (214KB) Download: Download full-size image