Boron-modified cobalt iron layered double hydroxides for high efficiency seawater oxidation

• DOI: 10.1016/j.nanoen.2021.105838
• Publication Date: 2021-01-30T12:22:05Z
• Authors: Libo Wu; Luo Yu; Qiancheng Zhu; Brian McElhenny; Fanghao Zhang; Chunzheng Wu; Xinxin Xing; Jiming Bao; Shuo Chen; Zhifeng Ren
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract Developing efficient and stable oxygen evolution reaction (OER) catalysts that can work well at high current densities for seawater electrolysis is desirable but remains a significant challenge. Here a novel and scalable strategy is developed to synthesize partially amorphous boron-modified cobalt iron layered double hydroxides (B-Co2Fe LDH). Benefiting from enhanced electronic kinetics and abundant active sites, this hierarchical nanosheet-nanoflake-structured B-Co2Fe LDH catalyst shows superb OER catalytic activity, requiring overpotentials of 205 and 246 mV to drive current densities of 10 and 100 mA cm−2, respectively, in 1 M KOH, along with a small Tafel slope of 39.2 mV dec−1. Its partial amorphousness feature leads to enhanced stability and corrosion resistance, which help the B-Co2Fe LDH catalyst to work well in the critical seawater condition. It requires overpotentials of 310 and 376 mV to drive current densities of 100 and 500 mA cm−2, respectively, in 1 M KOH seawater and can work continuously for 100 h without producing any hypochlorite. This work can enable the development of LDH catalysts for highly selective seawater oxidation using a general approach.