Cu Dope-Induced Defects for Enhanced Bifunctional Water Splitting Performance of CoFe₂O₄ and Its Forecasting Using LSTM Memory Cell

Abstract

Enhancing the efficiency of bifunctional electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is crucial for sustainable water splitting. In this study, the electrochemical performance of Cu-doped mixed spinel cobalt ferrites (CuCoFe) was systematically investigated, focusing on the role of oxygen vacancies in catalytic activity. Cu doping optimized charge transfer modulated the electronic structure and promoted oxygen vacancy formation, collectively enhancing reaction kinetics. Among the synthesized materials, CuCoFe0.5 exhibited the lowest overpotential, with 280 mV for OER and −143 mV for HER, alongside a cell voltage of 1.66 V during 20 h of continuous water splitting. The appreciable catalytic performance of CuCoFe0.5 was attributed to its enhanced electrochemically active surface area (ECSA) and abundant oxygen vacancies, which serve as active sites for HER and OER. Furthermore, its long-term stability highlights its potential as a durable electrocatalyst. The electrochemical performance forecasting (30%) was done using LSTM memory cell. Overall, study underscores the critical role of oxygen vacancies in improving catalytic efficiency, offering valuable insights for designing next-generation spinel ferrite-based electrocatalysts for water splitting.

Keywords

CuCoFe₂O₄ / induction–combustion method / LSTM forecasting / oxygen vacancy / water splitting

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2025 The Author(s). SusMat published by Sichuan University and John Wiley & Sons Australia, Ltd.