Atomic-level design of Pd-anchored NiFe-double-hydroxides with enhanced electronic effects for efficient water...

Water splitting is a cornerstone technology for a zero‑carbon society, yet its large-scale implementation is hindered by the inefficient oxygen evolution reaction (OER). Exploring low-cost, highly efficient, and kinetically favorable electrode materials is essential for advancing green hydrogen production. Additionally, current non-precious-metal catalysts suffer from sluggish charge-transfer kinetics, high intermediate adsorption barriers, and poor durability. Overcoming these fundamental kinetic and stability limitations remains the primary challenge for advancing sustainable water-splitting technologies. Herein, a facile one-step cationic lattice-regulation strategy is employed to obtain heterogeneous single-atom Pd-coupled NiFe-layered-double-hydroxides (NiFe-LDHs) with a typical PdO₄ coordination environment, strong d-p orbital state electronic interactions, and oxygen-related defects, enabling efficient bifunctional water splitting. Experiments and theoretical calculations have revealed the unique PdO₄ local coordination structure and strong d-p orbital state interaction, which synergistically enhance the mechanisms of oxygen and hydrogen evolution reaction and optimize the reaction pathway. Additionally, the unique geometric architecture accelerates electron transfer at the honeycomb edges, thereby enhancing electrochemical reactions, and facilitates proton diffusion while preserving electrocatalytic stability within the atomic-level two-dimensional layered framework of the catalyst.