Ultralow‐Overpotential Acidic Oxygen Evolution Reaction Over Bismuth Telluride–Carbon Nanotube Heterostructure with Organic Framework

Abstract The state‐of‐the‐art iridium and ruthenium oxides‐based materials are best known for high efficiency and stability in acidic oxygen evolution reaction (OER). However, the development of economically feasible catalysts for water‐splitting technologies is challenging by the requirements of low overpotential, high stability, and resistance of catalysts to dissolution during the acidic oxygen evolution reaction . Herein, an organometallic core–shell heterostructure composed of a carbon nanotube core (CNT) and bismuth telluride (Bi 2 Te 3 ) shell (denoted as nC–Bi 2 Te 3 ) is designed and use it as a catalyst for the acidic OER. The proposed catalyst achieves an ultralow overpotential of 160 mV at 10 mA cm −2 (geometrical), thereby outperforming most of the state‐of‐the‐art precious‐metal‐based catalysts. The low Tafel slope of 30 mV dec −1 and charge transfer resistance (R CT ) of 1.5 Ω demonstrate its excellent electrocatalytic activity. The morphological and chemical compositions of nC–Bi 2 Te 3 enable the generation of ─OH functional group in the Bi─Te sections formed via a ligand support, which enhances the absorption capacity of H + ions and increases the intrinsic catalytic activity. The presented insights regarding the material composition–structure relationship can help expand the application scope of high‐performance catalysts.