2026/04/16 by Yifan Cui, Yonghui Wang, Bo Li +9 · 1 voice
Energy · Engineering · Materials Science · #Electrocatalysts for Energy Conversion #Hydrogen Storage and Materials #Subcritical and Supercritical Water Processes
paper · pdf · doi:10.1007/s40820-026-02172-1
openalex created_date 2026/04/16 · openalex publication_date 2026/04/16 · openalex updated_date 2026/07/29
The scarcity of energy resources presents a significant obstacle to achieving sustainable development in modern society [ 1 , 2 , 3 ]. The electrolysis of water for hydrogen production serves as a highly promising energy storage method and has been widely employed to store intermittent energy sources such as wind and solar power [ 4 , 5 , 6 , 7 ]. Water electrolysis involves the oxygen evolution reaction (OER) at the anode and the hydrogen evolution reaction (HER) at the cathode [ 8 , 9 , 10 ]. Compared to the HER, the OER exerts a more significant influence on the overall efficiency of water splitting, due to its higher energy barrier and the intrinsic complexity of the four-electron transfer process [ 11 , 12 ]. During the OER, oxygen intermediates (OI) (e.g., OH*, O*, and OOH*) are formed, among which the adsorption strength of OH* is generally considered a key factor governing catalytic activity [ 13 , 14 ]. A moderate adsorption strength for OI is crucial for enhancing the overall water splitting activity of a catalyst. Significant research in recent years has focused on developing electrocatalysts for water splitting, with particular emphasis on reducing the overpotential ( ŋ ) [ 15 , 16 , 17 ], lowering costs [ 18 , 19 , 20 ], and enhancing stability [ 21 , 22 ]. Various oxides [ 23 , 24 , 25 , 26 ], hydroxides [ 27 , 28 ], and transition metal alloys [ 29 , 30 , 31 , 32 , 33 , 34 ] have demonstrated excellent performance in water splitting. In practical industrial applications, the operating performance of electrolyzers and the purity of the produced gases are strongly influenced by the quality of the feed water [ 35 , 36 ]. Meanwhile, regions hosting large-scale wind and solar energy harvesting systems frequently suffer from water scarcity [ 37 , 38 ]. Consequently, improving the stability of electrocatalysts under fluctuating current densities supplied by intermittent energy sources, while mitigating the adverse effects of water quality on catalytic performance, is pivotal for the practical deployment of hydrogen production via water splitting as an energy storage route.