Heterostructured MoO<sub>3</sub> Anchored Defect‐Rich NiFe‐LDH/NF as a Robust Self‐Supporting Electrocatalyst for Overall Water Splitting
Hualin Jiang, Yunjie Yu, Xueqing Duan, Pinghua Chen, Shuai Wang, Xianhua Qiu, Long Ye, Xinman Tu
Abstract
Abstract The rational design of inexpensive metal electrocatalysts with exciting catalytic activity for overall water splitting (OWS) remains a significant challenge. Heterostructures of NiFe layered double hydroxides (NiFe‐LDHs) with abundant oxygen defects and tunable electronic properties have garnered considerable attention. Here, a self‐supporting heterostructured catalyst (named MoO 3 /NiFe‐NF) is synthesized via a hydrothermal method to grow NiFe‐LDH with oxygen vacancies (O V ) in situ on inexpensive nickel foam (NF). Subsequently, MoO 3 is anchored and grown on the surface of NiFe‐LDH by electrodeposition. The obtained catalysts achieved outstanding oxygen/hydrogen evolution reaction (OER/HER, 212 mV/85 mV@10 mA cm −2 ) performance in 1 m KOH. Additionally, when MoO 3 /NiFe‐NF is utilized as the cathode and anode in OWS, a current density of 10 mA cm −2 can be obtained as an ultralow battery voltage of 1.43 V, a significantly lower value compared to the commercial electrolyzer incorporating Pt/C and IrO 2 electrode materials. Finally, density functional theory (DFT) calculations and advanced spectroscopy technology are conducted to reveal the effects of heterojunctions and O V on the internal electronic structure of the electrical catalysts. Mainly, the present study provides a novel tactic for the rational design of remarkable, low‐cost NiFe‐LDH electrocatalysts with heterostructures for OWS.