Crystalline/Amorphous Mo-Ni(OH)₂/Fe_xNi_y(OH)_3x+2y hierarchical nanotubes as efficient electrocatalyst for overall...

The development of efficient bifunctional catalysts for overall water splitting is highly desirable and essential for the advancement of hydrogen technology. In this work, Mo-Ni(OH)₂/Fe_xNi_y(OH)_3x+2y with hierarchical nanotube structure is constructed on flexible carbon cloth (CC) through simple electrochemical deposition and hydrothermal method. The hollow tube-structure is in favor of both exposing active sites and enhancing mass transfer capability. Moreover, the doping of Mo can enhance the electronic conductivity of heterostructures. The interfacial interaction between amorphous and crystal can enhance effectively the charge transfer kinetics across the interface. Therefore, Mo-Ni(OH)₂/Fe_xNi_y(OH)_3x+2y can achieve a low overpotential of 57 mV for hydrogen evolution reaction (HER) and 229 mV for oxygen evolution reaction (OER) at 10 mA·cm^-2. In addition, Mo-Ni(OH)₂/Fe_xNi_y(OH)_3x+2y needs a potential of only 1.54 V at 10 mA·cm^-2 for overall water splitting, and retains for a long period of time (60 h) reliable. The work will provide a valuable approach to the construction of highly efficient electrocatalysts for overall water splitting.