Oriented interlayered charge transfer in NiCoFe layered double hydroxide/MoO3 stacked heterostructure promoting the oxygen-evolving behavior

Oxygen evolution reaction (OER), the rate-limiting half reaction of water electrolysis, plays as a crucial role in improving the overall efficiency of the coupled hydrogen evolution. To date, earth-abundant OER catalysts have been extensively studied, while unfortunately their catalytic activity and operational stability still need to be further optimized. In this work, we fabricated a highly efficient OER catalyst based on two-dimensional (2D) NiCoFe layered double hydroxide (LDH)/MoO3 stacked heterostructure with enriched active sites and optimal electronic structure via an electrostatic-driven self-assembly process. The rough surface of the 2D heterostructure could offer abundant reactive sites for the pre-oxidation reaction, thereby leading to fast generation of the high-valence active species for OER, and the multi-metal synergy and oriented interlayered charge transfer could further enhance the intrinsic OER activity, finally resulting in enhanced OER performance with low overpotential, large current density, high intrinsic activity and excellent operational stability.