Fractal growth of copper electrodeposits

Black dendritic growths of copper were electrodeposited in steady-state diffusion-limited conditions onto an initially point-like cathode. Their spatial extent R was inferred from the increased current and their mass M from the total charge transferred. Fractal behaviour M∝RD was observed with D = 2.43 ±0.03, in good agreement with computer simulations of diffusion-limited aggregation.