This thesis presents a mechanistic study of interface-controlled electrodeposition of both single-metal and binary alloy systems, with emphasis on substrate & electrolyte engineering. A scalable strain-induced compaction–annealing process was developed to fabricate Cu(111)-textured pellets with up to 96% texture ratio. These substrates are reported to be highly effective in regulating the growth of basal Zn(002) films, enabling planar deposition with high reversibility & long-term stability. Compared to commercially available Cu foils, textured Cu(111) substrates significantly reduced the nucleation overpotential, enhancing the Zn plating/stripping efficiency (~99% over 2000 cycles) and lower voltage hysteresis. These results are noteworthy because they are achieved under high current density. X-ray diffraction revealed a predictable correlation of Zn(002) texture ratio on the prepared Cu(111) substrates, with analysis of degradation of the electrodeposit texture as a function of Zn deposition amount, yielding correlation lengths of the order of 100 μm. Electrochemical analysis coupled with XPS, SEM-EDS studies confirmed well-aligned homogeneous Zn deposits on Cu(111) compared to the disordered growth on polycrystalline Cu foil. To investigate the superior nucleation behavior of Zn on noble substrates like Cu, the role of underpotential deposition (UPD)—a phenomenon wherein Zn atoms adsorb and nucleate on the Cu surface at potentials more positive than the Zn²⁺/Zn equilibrium potential—was examined. In this system, UPD enables the formation of a compact and stable Zn layer, energetically favored by crystallographic registry and strong interfacial bonding. Motivated by these observations, the Zn–Cu binary system was investigated to understand the role of UPD in CuZn alloy formation, given the large disparity in their standard redox potentials. At low applied potentials, UPD facilitates the formation of a Zn–Cu α-brass solid solution. In the Zn-Cu binary aqueous electrolytes, at intermediate deposition potentials ( 1.0 to –1.6 V), 3D Cu–Zn clusters form via sustained UPD, acting as nucleation scaffolds that promote dense, planar Zn growth. Having established the influence of redox asymmetry and substrate interactions in the Zn–Cu system, the study transitions to the Ni–Co binary alloy system—a compositionally symmetric pair with near-identical redox potentials and atomic radii. This transition enabled the exploration of co-deposition dynamics in the absence of UPD effects, focusing instead on phenomena such as anomalous codeposition, interfacial adsorption, and crystallographic compatibility. Together, these investigations offer a comparative framework to understand how electrochemical symmetry, nucleation energetics and substrate engineering collectively dictate alloy formation and film quality. The analysis is initially conducted in an aqueous electrolyte, where redox-inverted co deposition is observed. However, due to pronounced hydrogen evolution reaction (HER) at higher overpotentials, it becomes difficult to establish a wider optimal deposition window. To address this, the study transitions to a polar aprotic solvent—Dimethyl sulfoxide (DMSO)—which mitigates HER exhibits passivation at high overpotentials, thereby suppressing interfacial instabilities and enabling compact Ni–Co alloy deposition. Furthermore, DMSO offers a wider and practically feasible voltage window for forming uniform Ni–Co solid solutions that closely replicate the bulk electrolyte composition.