Cobalt Phthalocyanine-Ketjen Black Hybrid Electrocatalyst for Efficient and Stable Alkaline Water Splitting

Abstract

The study aims to develop a sustainable energy framework focused on the evolution of energy conversion and storage applications with excellent performance, using lower-cost materials. Some of the electrochemical methods include water electrolysis (the hydrogen evolution reaction [HER] and oxygen evolution reaction [OER]), fuel cells, and metal–air batteries, which are eco-friendly in the production of hydrogen and electricity from sustainable sources, and are not only catalytically efficient but also have higher durability. Therefore, the purpose of this research is to develop novel metal-based molecular electrocatalysts for applications in clean energy production. A hybrid electrocatalyst, synthesized from 2, 10, 16, 24-tetrakis {4-((2-benzhydrylamino) phenyl) amino)-2-isocyanobenzonitrile} cobalt phthalocyanine (CoTBPc) supported on Ketjen Black (KB), was prepared and comprehensively characterized by using FTIR, NMR, Raman, UV–Vis, SEM–EDS, XPS, and other analytical methods. The CoTBPc+KB composite exhibits excellent hydrogen evolution reaction (HER) activity, with an overpotential of 229 mV at 10 mA cm-2 in 1.0 M KOH. The oxygen evolution reaction (OER) shows an overpotential of 289 mV, exhibits balanced bifunctional catalytic performance. The conductive KB framework facilitates rapid electron transfer and optimally exposes Co–N4 active sites. The catalyst also retains excellent operational stability for 47 hours (HER) and 52 hours (OER) during continuous electrolysis. These outcomes make CoTBPc+KB a durable and promising candidate in alkaline water-splitting applications.