Self-adaption of Zn introduced Ni-Fe layered double hydroxide for efficient and durable oxygen evolution reaction electrocatalysis

NiFe-based layer double hydroxides (NiFe-LDHs) have been widely considered to boost oxygen evolution reaction (OER) in alkaline solutions owing to their flexible layered structure and multi-functionality. We report on a class of M (M = Zn, Cu, Al, Cr, and Mn) introduced NiFe-x (x = 2-8) to further enhance the OER performance. The introducing element M is believed to play a decisive role in promoting the OER performance of NiFeM-4. As a result, the NiFeZn-4 exhibits low OER overpotential (204 mV to reach @10 mA cm(-2)) and turnover frequency (TOF, 0.572 s(-1)), respectively. Meanwhile, with the surface composition tuning, the obtained NiFeZn-4 appeared to underlie the high endurance of NiFeM-4, which can undergo 56 h i-t test with negligible activity loss and no apparent micromorphology and composition changes. Under long-term operation and periodic accelerated LSV tests, the NiFeZn-4 undergoes an adaptive process that helps optimize the impedance and introduced an OER durability enhancement (similar to 3.3 %).

Automated summary

NiFe-based layer double hydroxides (NiFe-LDHs) have been widely recognized for their ability to enhance the oxygen evolution reaction (OER) in alkaline solutions. In this study, the introduction of different elements (M = Zn, Cu, Al, Cr, and Mn) into NiFe-x (x = 2-8) is investigated to further improve the OER performance. The introduction of element M, particularly Zn, significantly contributes to the OER performance, with NiFeZn-4 demonstrating low overpotential and high endurance. Long-term operation and accelerated testing further optimize the impedance and enhance the OER durability of NiFeZn-4.