Composition and structure of arsenic-antimony alloy electrodeposited from acidic chloride solution
(College of Materials Science and Engineering, Zhejiang University of Technology, Hangzhou 310014, China)
Abstract: AsSb alloy (0.70-95.81 wt.% As) was prepared by electrodeposition in As(III) and Sb(III) contained electrolytes. The influence of electrolyte composition, hydrochloric acid concentration, and temperature on the composition and structure of AsSb deposits was studied. The electroreduction mechanism of As(III) and Sb(III) in hydrochloric acid solution was revealed via thermodynamic analysis. The results show that the increase of H+ concentration promotes the reduction of As(III), while the increase of Cl- concentration significantly inhibits the reduction of Sb(III). As a result, the As content in deposits increases gradually with the increase of hydrochloric acid concentration. Simultaneously, the phase structure of AsSb deposits evolves from crystalline to amorphous. When the As content is 24.55-33.75 wt.%, AsSb mixed crystal is obtained. The electrolysis temperature has little effect on the deposits composition, but the structure of deposits evolves from crystalline to amorphous with decreasing the temperature.
Key words: AsSb alloy; composition; phase structure; hydrochloric acid; thermodynamic analysis