In-situ anchoring of Pt single atoms on CoFeLDH for efficient alkaline hydrogen evolution reaction

The development of active single-atom catalysts for the alkaline hydrogen evolution reaction (HER) offers a promising strategy for lowering the cost of green hydrogen. Pt single atoms were in-situ anchored on layered double hydroxide (CoFeLDH) nanosheets using CV scanning electrodeposition with an optimal 40 cycles. The HAADF-STEM analysis confirmed the monoatomic dispersion of Pt in the CoFeLDH-Pt40cls catalyst, whereas XAFS showed that Pt was coordinated with four oxygens. Density functional theory calculation revealed a drop in the reaction energy barrier of the rate-limiting Volmer step during water splitting over the CoFeLDH-Pt40cls catalyst from 2.28 to 1.78 eV. Additionally, the free energy for hydrogen desorption decreased from 1.52 to −0.02 eV. The CoFeLDH-Pt40cls catalyst demonstrated excellent HER kinetics by achieving a −10 mA/cm2 current density at 45 mV overpotential. It also exhibited sustained high activity for around 100 h in stability studies.