Effect of thiourea and lead acetate on the deposition of electroless nickel

Thiourea and lead acetate were selected for comparison of their effects on deposition rate, crystallinity, surface morphology, and phosphorus content of electroless nickel deposit. In the investigated pH range 4–5, thiourea gives rise to higher deposition rates yet lower phosphorus contents than lead acetate. The results of SEM and AFM investigation show that coarse nodule and relatively rough surface morphology are obtained in the presence of thiourea. A higher pH value as well as a greater thiourea concentration tends to enhance the crystallization of the electroless nickel deposit.