Porous Co-Mo phosphide nanotubes: an efficient electrocatalyst for hydrogen evolution

The construction of efficient and low-cost bimetallic phosphide catalysts for hydrogen evolution is still in challenge. In this work, a series of porous Co-Mo phosphide nanotubes which are synthesized via in situ phosphidation process of CoMoO4 nanorods precursor at different phosphatization temperature have been used for hydrogen evolution reaction (HER). X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy, X-ray photoelectron spectroscopy and N-2 adsorption-desorption experiments were used to characterize the as-synthesized Co-Mo phosphide nanotubes. Results indicate that the phosphatization temperature is the key factor in the formation process of tube-like structure. The possible formation mechanism of Co-Mo phosphide nanotubes was further proposed. Additionally, the as-synthesized CoMoP-600 nanotubes displayed the highest HER catalytic performance and long-time durability in 0.5 M H2SO4 solution. The high catalytic performance of CoMoP-600 catalyst may be attributed to the favorable composition and the large surface area. This study shines a light in the application of bimetallic catalysts for the HER and provides us a new way to design and synthesize porous hollow tube-like structure materials.