Self-assembly of novel cobalt iron phosphate nanoparticles for the solid-state supercapattery and high-performance hydrogen evolution reaction

In this article, we report the preparation of novel cobalt iron phosphate nanoparticles which are self-assembled for energy storage, energy conversion, and sustainability. The self-assembled nanoparticles provide an efficient pathway for the transfer of electrons from the bulk of the materials to the interface of the electrode. This hypothesis has been derived from the analysis based on the electrochemical results for the supercapacitor-based energy storage and hydrogen evolution. The electrode consisting of self-assembled nanoparticles exhibits a maximum specific capacity of 280 C g-1 at a specific current of 1 A g-1. The cyclic voltammetric results suggest the prominent charge storage is by the faradaic reaction which has been concluded from Dunn's approach. The supercapattery device utilizing activated carbon (AC) as the negative electrode and cobalt iron phosphate as the positive electrode exhibit a specific capacity of 210 C g-1 at 2 A g-1 while the specific energy of 47.6 Wh kg-1 at 1.6 kW kg -1. Furthermore, the electrode actively catalyzes the electrochemical hydrogen evolution reaction and it can be lowering the overpotential required by the hydrogen generation. It exhibits the overpotential of 197 mV while the electrode represents the long-time (24 h) consistency for hydrogen production. Theseresults indicate that the novel cobalt iron phosphate nanoparticles could be a potential candidate for energy storage and conversion purposes.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

In this article, we report the preparation of self-assembled cobalt iron phosphate nanoparticles for energy storage and conversion. These nanoparticles provide an efficient pathway for electron transfer and exhibit high specific capacity and energy. The electrode composed of self-assembled nanoparticles also shows excellent catalytic activity for the hydrogen evolution reaction and long-time consistency for hydrogen production. These findings suggest that the novel cobalt iron phosphate nanoparticles have great potential for energy storage and conversion applications.