Interfacial engineering of heterostructured CoTe@FeOOH nanoarrays with tailored d-band centers for electrocatalytic oxygen evolution

Abstract

Efficient and affordable electrocatalysts are crucial for advancing hydrogen energy. Water electrolysis for hydrogen production is the dominant energy conversion method. However, the oxygen evolution reaction (OER) faces challenges due to high activation energy. Unlike sulfides and selenides, transition metal tellurides exhibit a superior conductivity and mass transport rate. Interfacial engineering is a potential solution due to its ability to modulate physical and chemical properties. However, research on interfacial engineering for the OER remains limited. This study employed a hydrothermal method to prepare cobalt telluride (CoTe) nanoarrays supported by nickel foam. Additionally, the fast interfacial method was utilized to construct a CoTe@FeOOH nanointerface. The coupling of CoTe and FeOOH significantly enhanced the catalytic activity for the OER. The results show that CoTe@FeOOH exhibited favorable performance with a Tafel slope of up to 69.9 mV dec⁻¹ and a low overpotential of 325 mV at 100 mA cm⁻². Theoretical calculations indicated that a heterogeneous interface comprised of FeOOH and CoTe can surmount the reaction energy barriers of intermediates in the OER process. CoTe@FeOOH's small size, heterogeneous structure, and synergistic effects can be fully exploited, providing valuable insights into the design of innovative electrocatalysts.