Terpyridine–metal architectures (Zn, Cu, Fe) for energy storage: electrochemical analysis and theoretical modeling

The design and investigation of metal complexes (C1-C6) featuring terpyridine ligands have gained significant attention due to their promising roles in energy storage technologies. In this study, we report the electrochemical behavior of Zn(II), Cu(II), and Fe(II) complexes incorporating terpyridine-based scaffolds. This study uniquely introduces alkyl- and alkoxy-substituted terpyridine metal complexes for application in electrochemical energy storage, demonstrating that these structural modifications effectively optimize redox activity and facilitate improved charge transport characteristics. Their electrochemical behavior was evaluated using cyclic voltammetry, revealing distinct redox characteristics and favorable reversibility profiles, particularly in the Cu(II) system, which underscores its potential as a redox-active center in energy-related applications. Complementary density functional theory (DFT) calculations were performed to elucidate the electronic structures, frontier molecular orbitals, and charge distribution, offering detailed insights into their redox properties and stability. Correlation between experimental findings and computational results highlights the influence of the metal center on the electronic modulation of the terpyridine core. The integrated electrochemical and theoretical analyses suggest that these complexes hold considerable promising nature as functional materials in next-generation energy storage systems.