Integrated iron phosphides and cobalt oxide electrocatalyst for enhanced hydrogen and oxygen evolution reactions: A study on activity and stability factors

The development of long-lasting, cost-effective, and efficient electrocatalysts is critical for obtaining exceptionally productive electrocatalytic hydrogen evolution and oxygen evolution reactions via water splitting in industrial settings, particularly for the generation of renewable hydrogen (H₂). In this study, the homogeneous integrated electrode (FeP/Co₃O₄/CF) is successfully produced using a facile pre-oxidation process that turns porous foams made of cobalt into a separate cobalt supply. The resultant materials are characterized via different analytical techniques like X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), elemental mapping and BET to confirm the structural, morphological, elemental and textural properties. This well-built integrated electrode is made of chemically connected FeP, Co₃O₄, and Co foam, making it an extremely active, long-lasting, and adaptable catalyst. The FeP/Co₃O₄/CF nanocomposite electrode has obtained 10, 500, and 1000 mAcm⁻² current densities at overpotentials of 52, 148, and 356 mV respectively for hydrogen evolution reaction (HER) and 192, 278, and 336 mV, respectively for the oxygen evolution reaction (OER). The exceptional performance can be attributed to the creation of an in situ tightly bound heterojunction between FeP and Co₃O₄. As a result, the FeP/Co₃O₄/CF integrated electrode is a highly promising choice for widespread application in industrial water electrolysis. Its self-supporting construction, integrated design, incorporation of phosphides, capacity to manage large current densities, and remarkable performance even when subjected to high-temperature electrolysis conditions are notable features.