Electroless, diffusion limited aggregation of lead dendrites

Abstract

• Lead dendrites with fractal characteristics deposit from lead nitrate gel solutions using metallic zinc. • The mechanism of lead fractal formation is explained in the Diffusion Limited Aggregation context. • Fractal dimension and percent coverage of the aggregates have similar variation trend. Two-dimensional lead Pb dendritic systems are prepared by electroless deposition from a lead nitrate gel solution and a zinc Zn metal cylinder in a circular cell. The box counting method is used to confirm that the lead dendritic structures obtained have fractal character. Results show that the fractal dimension of the dendrites formed is affected by the lead nitrate concentration and the medium properties which is varied by changing the percentage of gelatin in the solution. Both variables affect migration and aggregation of the lead particles and hence the physical emergence of the system. It was found that the fractal dimension has a maximum value for the aggregate formed from 0.06 M Pb(NO 3 ) 2 in 5 % gelatin. In addition, the percent coverage of the lead deposits was determined and showed analogous variation with the fractal dimension over the range of Pb(NO 3 ) 2 concentration and gelatin percentage studied.