Impressed-Current Corrosion towards Phase-Engineered Nickel-Iron Hydroxide Heterostructures for Prominent Oxygen Evolution Reactions

Abstract

Under harsh industrial operating conditions, nickel/iron layered double hydroxides (NiFe-LDH) are a highly promising electrocatalyst for oxygen evolution reaction (OER). However, the catalyst's activity and stability remain challenging. In this study, an oxygen vacancies NiFe-LDH/FeOOH heterostructure catalyst with a smaller interlayer spacing and amorphous structure was prepared using the impressed-current corrosion method. The growth of FeOOH was controlled, forming a heterogeneous structure catalyst with a large heterogeneous interface area, which increased the active area of the catalyst. Meanwhile, the heterojunction induces critical interfacial electronic modulation, leading to significantly enhanced catalytic activity and stability. Moreover, it was revealed that the impressed-current corrosion method can be used to prepare superior electron transfer NiFe-LDH catalysts, enhancing the catalyst's activity and the speed of current response. Under alkaline conditions, at a current density of 1000 mA cm−2, the OER has a low overpotential of only 309 mV and can operate stably for 14000 h (more than one year). Additionally, in the case of current fluctuations, this catalyst can respond quickly and has a durability of 450 h. This preparation method and a comprehensive understanding can provide guidance for the design of high-performance NiFe-LDH electrocatalysts.

Keywords: Electrocatalysts, Interface Engineering, Oxygen evolution reaction, Layer double hydroxide (LDH), Corrosion Engineering