The Impact of Gelatin on the Electrodeposition Behavior and Microstructure of Copper in Industrial Electrolyte Solutions

Abstract

With the advancement of technology and the rapid rise of the battery industry, the demand for high-quality copper is gradually increasing. Additives can refine the grain structure of the deposition layer and improve the electrocrystallization behavior, thereby optimizing the structural and physicochemical properties. Gelatin, as an important additive, has a significant impact on the electrocrystallization behavior and microstructure of copper in industrial electrolytes. It regulates the copper electrodeposition process through mechanisms such as adsorption, nucleation, and complexation, enhancing the structure and performance of the deposition layer. This study employs linear sweep voltammetry (LSV), cyclic voltammetry (CV), and chronoamperometry (CA) to investigate the effect of gelatin on the electrocrystallization behavior of copper in industrial electrolytes. Scanning electron microscopy, backscattered electron diffraction, and X-ray diffraction are used to analyze the microstructure, grain size, and preferred orientation of the copper deposition layer, exploring the influence of the organic additive gelatin on the grain refinement and crystal growth orientation of the copper deposition layer in industrial electrolysis.The results show that the addition of gelatin causes a negative shift in the copper deposition potential, increases cathodic polarization, reduces nucleation relaxation time, and refines the grains in the copper deposition layer. However, gelatin does not change the nucleation or growth mechanism of copper. At a gelatin concentration of 60 mg·L-1, the overpotential is at its maximum, the nucleation rate is the fastest, and the grain size of the deposition layer is minimized to 0.69 µm with a surface roughness of 199 nm. The deposition layer exhibits dual orientation growth of the (200) and (111) crystal planes, preventing coarse grain growth in a single direction. Therefore, the optimal concentration of gelatin in industrial electrolytes is 60 mg·L-1, which can significantly improve the quality of electrolytic copper and meet industrial production requirements.