Nitrogen-doped carbon microfibers decorated with palladium and palladium oxide nanoparticles for high-concentration hydrogen sensing

Hydrogen (H2) sensing materials with tuned geometrical shapes and dopants may contribute to H2 sensing performance, however, their synthetic approaches need further exploring. Here, shape -controlled nitrogen -doped carbon microfibers decorated with palladium and palladium oxide nanoparticles (Pd/PdO NPs@C/N MFs) have been prepared by combined electrospinning, annealing and chemical deposition. Typically, the C/N MFs of -224 nm in diameter are observed with amorphous crystallization, around which the Pd/PdO NPs (-20 nm in diameter) are randomly decorated. Beneficially, Pd/PdO NPs@C/N MFs present high -concentration sensing toward 0.01-30 v/v% H2 at room temperature. Theoretically, the nitrogen dopants in PVP contribute to anchoring the growth of Pd/PdO NPs, leading to stable decoration on the surface of MFs. The excellent sensing performance might be interpreted as the synergistic effect that Pd/PdO NPs@C/N MFs expose more adsorption sites, Pd adsorbs H2 to form PdHx intermediates, PdO alters the electronic state of Pd to assist the adsorption of H2, and C/N MFs serve as the support and boost the electron transfer. Practically, the simulation utilizing Pd/ PdO NPs@C/N MFs to detect H2 leakage has been conducted with reliable sensing.