Pb-doped NiFe layered double hydroxide for efficient and durable seawater oxidation at high current densities
Yifan Wu, Shengjun Sun, Tong Li, Chaoxin Yang, Zhengwei Cai, Zixiao Li, Yuchun Ren, Dongdong Zheng, Yongsong Luo, Fatma A. Ibrahim, Mohamed S. Hamdy, Xuefei Liu, Yang Luo, Yanqin Lv, Xuping Sun, Bo Tang
Abstract
Seawater electrolysis holds great promise for sustainable green hydrogen production, but it is challenged with chloride-induced corrosion. Herein, we demonstrate the hydrothermal preparation of Pb-doped NiFe layered double hydroxide on Ni foam (Pb-NiFe LDH/NF) for alkaline seawater oxidation electrocatalysis. Our Pb-NiFe LDH/NF requires a low overpotential of only 381 mV to attain a current density of 1000 mA cm<sup>−2</sup>, superior to its NiFe LDH/NF counterpart (423 mV). Additionally, it operates continuously for 1000 h with negligible performance degradation and minimal active chlorine production. In situ Raman spectroscopy analysis reveals that Pb incorporation facilitates catalyst surface reconstruction, thereby enhancing oxygen evolution reaction activity. Importantly, Pb selectively adsorbs free Cl<sup>−</sup> to form stable Pb-Cl species under the influence of an applied electric field. This process creates a Cl<sup>−</sup>-free layer near the anode surface, thereby enhancing the catalyst’s chlorine corrosion resistance.