In-situ construction of 3D hetero-structured sulfur-doped nanoflower- like FeNi LDH decorated with NiCo Prussian blue analogue cubes as efficient electrocatalysts for boosting oxygen evolution reaction

At present, it is urgent for us to develop non-noble metal-based catalysts with abundant reserves and high efficiency towards oxygen evolution reaction (OER) in water electrolysis devices. Herein, cubic NiCo-Prussian blue analogue (PBA)/ flower-like FeNi layered double hydroxide (LDH) heterostructure was facilely in-situ formed on porous nickel foam (NF) via hydrothermal strategy coupled by subsequent sulfurizing treatment (named as S-FeNi LDH@PBA/NF), showing largely facilitated electron transfer over homogeneous counterpart. Also, we investigated the effects of different Fe/Ni feeding ratios on their catalytic properties in some detail. The as-prepared S-FeNi LDH@PBA/NF demonstrated the superior OER activity (e.g. only 243 mV of overpotential required for 50 mA cm2) and stability. Accordingly, using the catalyst as anode, the home-assembled S-FeNi LDH@PBA/NF//Pt/C/NF electrolyzer exhibited small Tafel slope (83.1 mV dec1) and ultra-stability, showing the potential feasibility in practical water electrolysis. This strategy provides a hopeful model to enhance the OER performance by effectively constructing advanced catalyst with promising heterostructure and optimal electronic structure. (c) 2021 Elsevier Inc. All rights reserved.

Automated summary

It is currently urgent to develop non-noble metal-based catalysts with abundant reserves and high efficiency for the oxygen evolution reaction (OER) in water electrolysis devices. In this study, a cubic NiCo-Prussian blue analogue/flower-like FeNi layered double hydroxide heterostructure was successfully formed in-situ on porous nickel foam via a hydrothermal strategy coupled with subsequent sulfurizing treatment. The catalyst demonstrated superior OER activity and stability, providing a hopeful model for enhancing OER performance.