Hydrogen gas sensing properties of microwave-assisted 2D Hybrid Pd/rGO: Effect of temperature, humidity and UV illumination

A novel microwave assisted two-dimensional (2D) hybrid material based on nanostructured reduced graphene oxide (rGO) doped with Pd nanoparticles (Pd/rGO) has been synthesised to investigate its hydrogen sensing performance at different operational conditions. The sensing performance has been evaluated at various operating temperatures (room temperature up to 120 °C), hydrogen concentrations (up to 1%), and relative humidity (up to ~44%). The material characterization of the hybrid Pd/rGO analysed by different techniques which confirms homogeneous distribution of Pd NPs (<35 nm) on the multi-layered porous structure of the rGO nanosheets (NSs) and forming the hybrid Pd/rGO NSs. Moreover, the fundamental hydrogen sensing mechanism as well as recovery enhancement by ultraviolet (UV) light are investigated. This work offers an environmentally friendly and energy-saving synthesis approach for hydrogen sensing with excellent control over experimental parameters which can lead to fabrication of a highly selective and sensitive hydrogen sensor.