Fabrication of a flexible H2 sensor based on Pd nanoparticles modified polypyrrole films

Novel flexible H2 gas sensors were fabricated by self-assembling the Pd-based complex and polypyrrole (PPy) thin films layer-by-layer on a plastic substrate and then reducing in-situ Pd-based complex thin film to a Pd-PPy thin film. Microstructural observations revealed that Pd nanoparticles (Pd NPs) formed on the surface of the PPy film. The effect of the amount of decorated Pd NPs on the response and stability of the Pd NPs-PPy thin film was investigated. The response of the PPy thin film was improved by the Pd NPs, supplying catalytically active sites for H2 gas molecules. The flexible H2 sensor that was made of Pd NPs-PPy thin film had a high performance with strongest response, good stability and high flexibility at room temperature. The flexible H2 gas sensor exhibited a strong response that was greater than that of sensor that was made of Pt-PPy at room temperature.