Redox Tweaks and Charge Transfer Alterations: Mn 2+ vs. Cu 2+ Doping for Enhancing OER Activity of CoFe‐LDH

ABSTRACT Designing self‐supported and durable layered double hydroxide (LDH) electrocatalysts is essential for enhancing alkaline oxygen evolution reaction (OER) development. In this study, we show a direct comparison of two fundamentally different dopant functions, Mn 2+ ‐driven “redox tweaks” and Cu 2+ ‐driven “charge‐transfer enhancement” achieved by controllably integrating both cations into CoFe‐LDH nanosheets by a simple electrodeposition approach. Complete structural and compositional analyses (XRD, FT‐IR, SEM‐EDS, HR‐TEM, and XPS) reveal uniform lattice interaction without secondary phase formation, as well as apparent morphological evolution. The Mn 2+ ‐doping enhances redox‐state tuning by enriching Co 3+ /Co 2+ redox centers enhancing metal–oxygen covalency and improving OH* and O* adsorption energies. This results in a higher electrochemically active surface area and significantly faster OER kinetics. On other side, Cu 2+ has higher intrinsic conductivity and lower uncompensated resistance but its weaker O/OH − interaction causes slower interfacial charge transfer and limited catalytic activity. The Mn (0.35 M) ‐doped CoFe‐LDH is a highly effective catalyst requiring only 279 mV to reach 100 mA cm −2 with a Tafel slope of 78 mV dec −1 . It outperforms Cu‐doped equivalents, pristine CoFe‐LDH and RuO 2 controls. After 100 h of continuous electrolysis, the nanosheet architecture and oxidation states remained unchanged, demonstrating exceptional structural durability. Overall, this study demonstrates that redox‐tweak dopant engineering can outperform conductivity‐centered techniques in regulating alkaline OER pathways providing a rational blueprint for the future design of transition‐metal LDH electrocatalysts.