Through a combination of advanced in situ and ex situ characterization techniques, as well as theoretical calculations, Huang demonstrated that these open Zn−N2 sites chemisorb hydroxyl groups from alkaline electrolytes under operational conditions, forming high-valence HO−Zn−N2 active sites.
The introduction of HO−Zn−N2 sites significantly reduced the overpotential for HER from 0.31 V (ZIF-8) to 0.07 V at 10 mA cm−2, substantially enhancing the electrocatalytic efficiency. Furthermore, the presence of these active sites decreased the band gap of the material, enabling visible light activity compared to the UV-limited ZIF-8. Density functional theory (DFT) simulations supported these findings, revealing that the HO−Zn−N2 sites facilitated water adsorption and dissociation, thus improving the overall HER performance. His work offers a promising pathway for designing advanced materials with optimized catalytic properties for energy-related applications.
The paper was recently published Open Access in Angewandte chemie and can be assessed through the following link: https://doi.org/10.1002/anie.202419913, opens an external URL in a new window