Construction of defective MnCo-LDH nanoflowers with high activity for overall water splitting

Manganese-cobalt layered double hydroxide (MnCo-LDH) is a kind of layered bimetallic hydroxide with good catalytic performance and stability for water decomposition. In this paper, a series of defective MnCo-LDH materials with different Mn/Co molar ratio was prepared by hydrothermal method. The results show that the MnCo-nanoflowers containing Mn and Co elements are successfully prepared, and all of them contain N, O, Mn and Co elements. The hydrogen evolution reaction (HER) catalytic performance of Co vacancy (VCo)-MnCo-LDH is better than that of commercial electrode Pt/C, and oxygen evolution reaction (OER) catalytic performance of Mn vacancy (VMn)-MnCo-LDH is better than that of commercial electrode RuO2. Two-electrode overall water splitting (OWS) test showed that the overpotential required by VMn-MnCo-LDH/NF||VCo-MnCo-LDH/NF and Pt/C/NF||RuO2/NF were 1.56 V and 1.72 V respectively at the current density of 10 mA cm−2, and the catalytic activity of the prepared defective MnCo-LDH is excellent bifunctional electrocatalysts for both HER and OER.