Layered Double Hydroxides Derived Prussian Blue Analogue Nanocage Confining NiCoP Nanoparticles as Efficient Bifunctional Electrocatalyst

Abstract

Designing metal electrocatalysts with excellent catalytic activity for efficient water separation is an ongoing challenge.Electrocatalytic hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal processes for efficient water electrolysis. The development of cost-effective, efficient, stable, and scalable bifunctional electrocatalysts is crucial for clean and renewable energy storage. In this study, a facile hydrothermal method followed by low-temperature phosphorylation treatment was employed to fabricate a nanocage of layered double hydroxide-derived prussian blue analogue (NiCoP@PBA), encapsulating NiCoP nanoparticles. This material was applied as a freestanding bifunctional nonprecious electrocatalyst for water splitting.The NiCoP@PBA composite exhibited outstanding catalytic properties for both HER and OER in the same alkaline medium, showcasing low overpotentials of 59 mV (HER ) and 263 mV (OER) at 10 mA cm-2. The superior HER catalytic activity was attributed to the well-dispersed NiCoP nanoparticles within the porous PBA framework. Moreover, the porous PBA skeleton not only provided abundant active sites but also served as spatial confinement, enhancing stability. The strong interfacial interaction between NiCoP and PBA accelerated charge transfer kinetics, significantly extending the electrocatalyst's service life.This study can also have excellent performance in other transition metal phosphides, which is of great significance in promoting efficient bifunctional water separation electrocatalysts and provides a broad prospect for the development of clean energy technology.

Keywords: Sustainable energy, Bifunctional electrocatalyst, Heterostructure, Overall water splitting