Electronic modulation of amorphous/crystalline NiFe LDH by atomic Pt loading enabling industrial hydrogen production in alkaline water and seawater

The reasonable development and design of high-efficiency and low-cost electrocatalysts for hydrogen evolution reaction (HER) under industrial current densities are imperative for achieving carbon neutrality, while also posing challenges. In this study, an efficient electrocatalyst is successfully constructed through electrodeposition methods, which consists of monodispersed Pt loaded on amorphous/crystalline nickel–iron layered double hydroxide (Pt-SAs/ac-NiFe LDH). The Pt-SAs/ac-NiFe LDH demonstrates an elevated mass activity of 17.66 A mg_Pt⁻¹ and a significant turnover frequency of 17.90 s⁻¹ for HER in alkaline conditions under the overpotential of 100 mV. Meanwhile, for alkaline freshwater and seawater, Pt-SAs/ac-NiFe LDH exhibits ultra-low overpotentials of 141 and 138 mV to reach 1000 mA cm⁻², respectively. Remarkably, it maintains stable operation for 100 h at 500 mA cm⁻², showcasing its robustness and reliability. In situ Raman spectra reveal that Pt single atoms (Pt-SAs) accelerate interfacial water dissociation, thereby enhancing the HER kinetics in Pt-SAs/ac-NiFe LDH. Furthermore, theoretical calculation results show significant electronic interaction between the Pt-SAs and the ac-NiFe LDH support. The interaction significantly enhances water adsorption and dissociation, and balances the adsorption/desorption of hydrogen intermediates, ultimately improving HER performance. This research provides a viable method for designing efficient HER catalysts for water electrolysis in alkaline freshwater and seawater under industrial current densities.