Well-defined Co–Pt–OH as “electronic pump” on Co-LDH nanocages for enhanced oxygen evolution reaction

The acceleration of electron transfer through the regulation of coordination environment of active sites is an effective way to improve reaction performances. Herein, cobalt layered double hydroxide decorated with sub-1 nm platinum clusters (Pt/Co-LDH) were synthesized for oxygen evolution reaction (OER). The integration of platinum unexpectedly induced unique nanocage structures assembled by ultra-thin LDH nanosheets via an in-situ redox process. The as-prepared Pt/Co-LDH nanocages exhibit high OER activity with a low overpotential of 265 mV at 10 mA cm−2. Experiments and density functional theory calculations indicate the high catalytic activity is mainly attributed to the strong interactions between Pt and Co-LDH, which can regulate the local coordination environment and electronic structures of cobalt. The well-defined Co–Pt−OH structures could help promote the adsorption energy of water molecules and reduce the energy barrier of rate-limiting step, benefiting from the enhanced electron transfer during the electrocatalytic process, playing the role of “electronic pump”. Furthermore, the novel in-situ redox synthetic strategy also presents a facile universality to obtain metal-doped (Pt, Au, Pd) Co-LDH nanocage structures.