Enhancing durability and activity toward oxygen evolution reaction using single-site Re-doped NiFeOx catalysts at ampere-level
Xiang Lyu, Naduvile Purayil Dileep, Yulia Pushkar, Max Pupucevski, J. Lattimer, Héctor Colón-Mercado, P. Ganesan, Matthew R. Ryder, Jong K. Keum, David A. Cullen, Haoran Yu, Harry M. Meyer, Jun Yang, Alexey Serov
Abstract
NiFeO x materials are known as among the most active catalysts toward oxygen evolution reaction (OER) for hydrogen generation in alkaline media. Nevertheless, the long-term durability of NiFeO x catalysts for OER is still too far to the industrial application. Herein, we prepared a NiFeReO x catalyst with single-site Re dopants and observed that the single-site Re dopants could significantly enhance the durability without compromising the activity. A cell voltage of 1.82 V without iR correction is noted at the current density of 3000 mA cm −2 in anion-exchange membrane water electrolyzer (AEMWE) with NiFeReO x catalyst, and a very small degradation is observed under 2000 and 1000 mA cm −2 , which remarkably outperforms the pristine NiFeO x . Additionally, the overpotential of 305 mV at 10 mA cm −2 is achieved with the NiFeReO x catalyst, which is lower than 50 mV compared with the pristine NiFeOx catalyst, together with a smaller Tafel slope of 54.3 mV dec -1 . The boosted OER durability and activity of the NiFeReO x catalyst could be attributed to the strong electron-withdrawing property of Re 7+ single atoms leading to the electronic structure optimization and stabilization of Ni/Fe active sites. Our insights propose a new path for designing NiFeO x catalysts with high durability and activity toward OER.