Effect of temperature on mechanism and kinetics of electrochemical nucleation of copper in ChCl-based deep eutectic solvents

Study of Copper Electrodeposition at a Very Low Temperature near the Freezing Point of Electrolyte

“…The growth process of deposited metal includes the following steps: the diffusion of solution metal ions to the vicinity of cathode, the electrochemical process of reduction through the interface between the cathode metal and the solution, and the electrocrystallization process of nucleation and growth of the reduced metal atoms on the cathode surface. Decreasing the temperature increases the electrolyte viscosity [19][20][21][22][23] and cathode surface diffusion layer thickness [5]. At the same time, it will reduce the diffusion coefficient of copper ions and copper atoms and the electrochemical reaction rate constant, which will decrease the adsorption of copper ions [24], the reduction [23][24][25], the surface diffusion of copper atoms [25,26], and other electrochemical processes of copper deposition.…”

“…As the temperature changes, the equilibrium potential moves in a positive direction, and the overpotential required for nucleation on the electrode surface decreases sharply. The author uses these factors to improve the threedimensional nucleation of copper and to obtain denser deposits [21]. M. D. Groner et al alternately exposed Al(CH 3 ) 3 and H 2 O to the low temperature electrodeposition state and found that the film density of Al 2 O 3 was low at a lower deposition temperature, the film surface was very smooth, the roughness value was also low, and it had good electrical properties after measurement.…”