Cai, Z., Zhou, D., Wang, M., Bak, S. M., Wu, Y., Wu, Z., Tian, Y., Xiong, X., Li, Y., Liu, W., Siahrostami, S., Kuang, Y., Yang, X. Q., Duan, H.*, Feng, Z.*, Wang, H.*, Sun, X.*
Angew. Chem. Int. Ed. 2018, 57, 9392-9396.
Exploring materials with regulated local structures and understanding how the atomic motifs govern the reactivity and durability of catalysts are a critical challenge for designing advanced catalysts. Herein we report the tuning of the local atomic structure of nickel–iron layered double hydroxides (NiFe-LDHs) by partially substituting Ni2+ with Fe2+ to introduce Fe-O-Fe moieties. These Fe2+-containing NiFe-LDHs exhibit enhanced oxygen evolution reaction (OER) activity with an ultralow overpotential of 195 mV at the current density of 10 mA cm−2, which is among the best OER catalytic performance to date. In-situ X-ray absorption, Raman, and electrochemical analysis jointly reveal that the Fe-O-Fe motifs could stabilize high-valent metal sites at low overpotentials, thereby enhancing the OER activity. These results reveal the importance of tuning the local atomic structure for designing high efficiency electrocatalysts.