PdPtAgCuNi high-entropy alloy functionalized SnO2 nanorods sensor for highly selective detection of hydrogen

Hydrogen (H 2 ) is a promising clean energy carrier, making reliable hydrogen sensors essential for safety monitoring and energy applications. A PdPtAgCuNi high-entropy alloy (HEA) was integrated with SnO 2 nanorods to enhance hydrogen sensing performance. The resulting HEA-SnO 2 sensor exhibited a response of 1961.5 toward 200 ppm H 2 and a low detection limit of 20 ppb. The sensor also exhibited rapid response and excellent hydrogen selectivity. Experimental results and density functional theory (DFT) calculations indicate that the enhanced sensing behavior originates from the combined electronic and catalytic effects of the HEA. The interfacial Schottky barrier enhances electron depletion layer modulation, while the HEA surface promotes hydrogen activation and dissociation. This study demonstrates the potential of HEAs as effective sensitizers for high-performance hydrogen sensors.