Electrospun P–Mo–W–Ni multicomponent composite oxides for hydrogen evolution reaction

Novel crystalline Ni10W12Mo12P2O87 multicomponent composite oxides were synthesized through electrospinning heteropoly acid H3PMo12O40 (PMo12), H3PW12O40 (PW12) and NiAc2-contained polyvinyl alcohol aqueous solution with a PMo12:PW12:NiAc2 ratio of 1:1:10. Then, calcination is performed under mild conditions. The characterization results of the structure, composition and morphology observed from x-ray powder diffraction, thermogravimetric analysis, field-emission high-resolution transmission electron microscopy, scanning electron microscopy, Raman spectroscopy and Fourier transform infrared illustrated that multicomponent composite oxides consisted of MoO3, WO3, NiWO4, NiMoO4 and P2O5. The electrochemical method could explain that the crystalline Ni10W12Mo12P2O87 presented better hydrogen evolution properties than those fabricated from PMo12 to NiAc2 or PW12 to NiAc2 equaling to 1:5, individually, and the corresponding Tafel slope was 40 mV/decade. In addition, the presence of NiMoO4 and NiWO4 compounds was crucial to improve the electrocatalytic hydrogen evolution properties of the catalyst.