Abstract:

The article demonstrates for the first time that α-arbutin is a highly efficient, persistent inhibitor of zinc in concentrated alkaline electrolyte. The bifunctional architecture integrates a glucose unit that enhances solubility and interfacial assembly with a phenolic segment that firmly binds to zinc, resulting in a dense protective coating. In gravimetric and electrochemical experiments conducted in 6 M KOH, α-arbutin achieves a maximum inhibition of 96.5% at 140 ppm, with polarization and impedance data demonstrating concurrent suppression of anodic dissolution and cathodic hydrogen evolution. Langmuir-type adsorption and a ΔGads of around −33.8 kJ/mol suggest spontaneous mixed physisorption and chemisorption, corroborated by film development detected using SEM/EDX, FT-IR, and XPS analyses. Density-functional calculations reveal that hydroxyl and phenolic sites are the primary donors, corroborating the experimentally determined binding mechanism. In addition to corrosion control, α-arbutin boosts the performance of Zn–air cells by enhancing discharge stability and cycling durability under practical current loads. Collectively, these findings establish α-arbutin as a dual-purpose additive that combines green corrosion protection with enhanced performance in alkaline zinc energy systems.