Construction of Pt Single-Atom and Cluster/FeOOH Synergistic Active Sites for Efficient Electrocatalytic Hydrogen Evolution Reaction

The design of efficient catalysts that synergistically promote *H2O decomposition, H2 formation, and desorption is critical to accelerate hydrogen evolution reaction (HER) kinetics but remains a significant challenge. Herein, we design an efficient catalyst of Pt/FeOOH@NiFe LDHs with Pt single-atom and cluster distribution induced by amorphous FeOOH. The Pt/FeOOH@NiFe LDHs with a low Pt content of 2 wt % exhibit ultralow HER overpotentials of 20 and 85 mV in alkaline media (5 and 40 mV in acidic media) to achieve the current densities of 10 and 100 mA cm–2. The overpotentials of specific activity normalized by the electrochemically active surfaces (ECSA) are 100 mV@0.2 mA cmECSA–2 and 140 mV@0.4 mA cmECSA–2. The Tafel slope is 51 mV dec–1, and the HER process follows the Volmer-Hyrovsky mechanism. Moreover, the overall water splitting requires only low voltages of 1.46 V@10 mA cm–2 and 1.61 V@100 mA cm–2, which are better than most reported catalysts. Experimental and theoretical studies show that the amorphous FeOOH can induce the formation of Pt single-atom and cluster with electron redistribution, and the formed Pt single-atom and cluster/FeOOH synergistic active sites exhibit superior HER performance. The amorphous FeOOH in Pt/FeOOH@NiFe LDHs facilitates the adsorption and activation of H2O, and the Pt single-atom and cluster play a key role in the formation and desorption of H2, synergistically accelerating the HER kinetics.