Dual-functional amphiphilic copolymer for enhanced dispersion and humidity tolerance of high-performance SnO2/Pd hydrogen sensors

The development of reliable hydrogen sensors with high sensitivity, selectivity, and environmental stability is essential for the widespread adoption of hydrogen-based energy technologies. Herein, we report a highperformance chemiresistive hydrogen sensor based on uniformly dispersed SnO2/Pd nanoparticles using a comb-structured amphiphilic copolymer, poly(2, 2, 3, 3-tetrafluoropropyl methacrylate)-co-poly(oxyethylene methacrylate) (PTPO). The incorporation of PTPO effectively prevents aggregation of nanoparticles, enabling the formation of uniform, porous sensing films with improved interfacial contact and enlarged active surface area. In addition, the presence of PTPO layer improves humidity-tolerance of the sensor by hindering interactions between water molecules and the SnO2 surface. At an optimal PTPO content of 10 wt%, the sensor exhibits more than a twofold increase in response, along with faster response and recovery times compared to the pristine SnO2/Pd sensor. Furthermore, the SnO2/Pd/PTPO sensor demonstrates enhanced selectivity, long-term operational stability, and outstanding performance under high humidity conditions. The facile addition of the PTPO copolymer serves as both an effective dispersant and a humidity-resistant layer, offering a promising and scalable strategy for the fabrication of advanced metal oxide-based gas sensors. This approach demonstrates significant potential for practical hydrogen detection in industrial and environmental monitoring, where superior reliability and humidity tolerance are crucial.