Surface engineering of 1D Na-doped Pd/WO3 nanorods for chemiresistive H2 sensing

The design of novel functional nanostructures for advanced chemical engineering field is of great importance. In this work, Pd-modified Na-doped WO 3 nanorods are rationally designed for rapid and detection of hydrogen, which is a green and clean energy in modern industry. Notably, and H + as well as citrate ions play an important role in the formation of 1D nanorods, and the morphology formation mechanism is explored. Here, inspired by the novel Pd-modified Na-doped WO 3 nanorods structure, the Pd-400-Na/WO 3 NRs exhibit high sensing ability with ultra-high response to hydrogen (R a /R g = 218@25 ppm) and fast response time (3 s). The combination of experimental and theoretical results shows that Na doping effectively modulates the d-band center of Pd and enhances activation and desorption of H 2 on the Pd surface. The 1D porous structure also facilitates the diffusion of H 2 within the framework, and accelerate the charge transformation. Meanwhile, the surface Pd 0 sites are assigned as the surface active sites for H 2 adsorption and activation, and Pd 2+ sites facilitate the desorption process. Our work paves the new insights for the design of high performance H 2 sensing materials.