First-Principles Investigation of YBa2Cu3O7 Layered Perovskite as a High-Performance Electrocatalyst for the Oxygen Evolution Reaction (OER)

This paper presents a comprehensive Density Functional Theory (DFT + U ) investigation into the potential of the layered cuprate perovskite, YBa2Cu3O7 (YBCO), as a high-performance electrocatalyst for the Oxygen Evolution Reaction (OER). Historically studied for its superconductivity, YBCO’s unique orthorhombic structure featuring highly conductive quasi-one-dimensional Cu-O chains offers intrinsic electronic advantages that bypass common conductivity limitations in standard oxide electrocatalysis. The study begins with rigorous structural validation and methodological refinement, justifying the use of DFT + U to accurately capture the strongly correlated nature of the Cu 3d electrons. Surface stability analysis under operando conditions identifies the CuO chain termination as the preferred active interface, where the B-site Cu atoms serve as the catalytic centers. By calculating the electronic descriptor, the O 2p-band center (ϵO-2p), and constructing full Gibbs free energy (ΔG) diagrams, a low theoretical OER overpotential (ηOER) is predicted. Furthermore, analysis of the material’s defect chemistry specifically the facile formation of oxygen vacancies (VO) in the Cu-O chains strongly suggests that activity is driven by the energetically favorable Lattice Oxygen Mechanism (LOM). The LOM pathway, facilitated by the high electronic conductivity of the chains, allows YBCO to circumvent the scaling constraints inherent to the conventional Adsorbate Evolution Mechanism (AEM). These findings theoretically position YBCO and similar A2B2B’O7 − δ layered structures as promising, earth-abundant alternatives to precious metal catalysts for highly efficient electrochemical water splitting.