Polymeric Ionomer-Mediated Electrodeposition of Mn(OH) 2 Nanonets on Carbon Nanofibers toward Enhanced Electrochemical Performance

Engineering metal hydroxide–carbon interfaces with controlled microstructure is critical for optimizing electrochemical performance, yet conventional fabrication strategies often suffer from non-uniform deposition and weak interfacial coupling. Herein, we report an electrodeposition-driven strategy to construct Mn(OH) 2 -decorated carbon nanofiber (CNF) electrodes with tunable morphology and enhanced electrochemical activity. Importantly, polymeric ionomer (Nafion) is employed as a microenvironment-regulating medium, functioning as a binder to govern Mn(OH) 2 growth. Specifically, systematic modulation of Nafion concentration induces distinct Mn(OH) 2 deposition morphologies, which in turn give rise to pronounced differences in electrical conductivity and interfacial charge-transfer kinetics. The optimized Mn(OH) 2 /CNF electrodes exhibit the enhanced oxygen evolution reaction activity with lowered charge-transfer resistance, demonstrating the strong correlation between deposition microenvironment, morphological evolution, and electrochemical performance.