Three-dimensional ordered FeTe-SmCoO₃ nanocomposite: As efficient electrocatalyst for water oxidation

In this work, FeTe-SmCoO₃ is fabricated through a hydrothermal method and then coated on a stainless steel (SS) substrate to enhance the electrocatalytic performance. The crystal structure, surface chemical state, and morphological features of pure (FeTe and SmCoO₃) and heterogeneous catalysts (FeTe-SmCoO₃) are determined via XRD, XPS, and TEM/EDX techniques. The fabricated FeTe-SmCoO₃ electrocatalyst is attributed to the particular morphological design resulting from the synergistic effect of FeTe and SmCoO₃ phases. The as-developed high exposure level of active sites with structural transformation greatly promoted the oxidation property with an overpotential only of 199 mV to derive a current density of 10 mA/cm², also observed a small Tafel slope of 72 mVdec⁻¹ with extraordinary stability of 90 h. The modified heterogeneous catalyst provides outstanding catalytic behavior toward OER in the alkaline solution, due to flexibility and multiple accessible oxidation states of samarium, cobalt, and iron ions. The catalyst not only acquires additional reaction sites and opens up new channels through the dispersion of the metal centers, but also achieves quick electron transfer in FeTe-SmCoO₃ nanocomposite through the interconnection between two phases.