Construction of hetero-phase Mo2C-CoO@N-CNFs film as a self-supported Bi-functional catalyst towards overall water splitting

• A self-standing Mo 2 C-CoO@N-CNFs film catalyst is electrospun for both HER and OER; • Nanoscale hetero-phase Mo 2 C-CoO particles are well-distributed in N-doped carbon nanofiber film; • Mo 2 C-CoO@N-CNFs film owns good wettability, multi-pore structure and high electrical conductivity/active sites; • The Mo 2 C-CoO hetero-phase accelerates the kinetics of HER and reduces energy barrier of OER; • The bi-function Mo 2 C-CoO@N-CNFs-8 film displays superb catalytic for alkaline overall water splitting. It is an enormous challenge to develop low-cost non-noble metal bi-functional catalysts toward overall water splitting. The efficient water decomposition electrocatalysts need both intrinsic activities determined by electronic structure and superb mass transfer ability. For this, in the contribution, an efficient self-supported bi-functional catalyst, i.e. , nanoscale hetero Mo 2 C-CoO encapsulated in N-doped carbon nanofibers (Mo 2 C-CoO@N-CNFs), is designed and fabricated with facile electrospinning avenue. Density functional theory and electrochemical investigation manifest that the synergistic effect of bimetallic Mo/Co accelerates kinetics of hydrogen evolution reaction (HER) and lowers the energy barrier of oxygen evolution reaction (OER). Thanks to the structural and compositional merits, the optimized integrated Mo 2 C-CoO@N-CNFs film demonstrates remarkable catalytic activities in both OER and HER, and renders a current density of 10 mA cm −2 at 1.56 V when used for alkaline whole water cracking. The design concept here provides insights for future rational construction of advanced water decomposition catalysts.