Molybdate intercalated CoFe-layered double hydroxides for overall water splitting

The exploration of bifunctional electrocatalysts with abundant resources and excellent catalytic performances is currently one of the fundamental conditions for the development and promotion of hydrogen energy technology. In this work, an extremely simple one-step hydrothermal strategy was proposed for the preparation of CoFe-layered double hydroxide nanosheets intercalated with molybdate (CoFe-LDH-MoO42-). The well-designed electrocatalyst exhibits outstanding catalytic activity due to the adjustability of two-dimensional layered materials, synergistic effects of Co and Fe, as well as expanded inter-layer distance, which necessitates overpotential of 74 and 92 mV at 10 mA cm−2 for HER and OER, respectively. When the CoFe-LDH-MoO42- is assembled in a two-electrode system, it requires a cell voltage of 1.50 V to drive 10 mA cm−2. The innovative exploration of this work offers a novel approach to construct multifunctional electrocatalysts for efficient and stable total water splitting.