Influence of the type of electrolyte on the morphological and crystallographic characteristics of lead powder particles

Abstract

Lead electrodeposition processes from basic (nitrate) and complex (acetate) electrolytes were mutually compared by scanning electron microscopy and X-ray diffraction investigation of the produced powder particles. The shape of dendritic particles strongly depended on the type of electrolyte. Dendrites composed of a stalk and weakly developed primary branches (the primary type) were predominantly formed from the basic electrolyte. Ramified dendrites composed of a stalk and of both primary and secondary branches (the secondary type) were mainly formed from the complex electrolyte. In both types of powder particles, Pb crystallites were predominantly oriented in the (111) plane. The formation of powder particles of different shapes with strong (111) preferred orientation is discussed and explained by consideration of the general characteristics of the growth of crystals in electrocrystallization processes.

Procesi elektrohemijskog taloženja olova iz osnovnog (nitratnog) i kompleksnog (acetatnog) elektrolita su bili međusobno upoređeni tehnikom skenirajuće elektronske mikroskopije i rendgensko-difrakcionom analizom proizvedenih čestica praha. Oblik dendritičnih čestica je snažno zavisio od tipa elektrolita. Dendriti sastavljeni od stabla i slabo razvijenih grana (primarni tip) su bili predominantno formirani iz osnovnog elektrolita. Razgranati dendriti sastavljeni od stabla i od primarnih i sekundarnih grana (sekundarni tip) su bili uglavnom formirani iz kompleksnog elektrolita. U oba tipa praškastih čestica kristaliti olova su bili dominantno orijentisani u (111) ravni. Formiranje praškastih čestica sa strogom (111) orijentacijom je bilo diskutovano i objašnjeno razmatranjem opštih karakteristika rasta kristala u procesima elektrokristalizacije.