酸性氯化物体系中电沉积AsSb合金的组成与结构

Composition and structure of arsenic−antimony alloy electrodeposited from acidic chloride solution

通过电沉积法在含As(III)和Sb(III)的盐酸溶液中制备AsSb合金(0.70%~95.81%As,质量分数),并研究电解质成分、盐酸浓度和温度对AsSb合金组成和结构的影响。通过热力学分析As(III)和Sb(III)在盐酸溶液中的电还原机理。结果表明,H+浓度的增加能促进As(III)的还原,而Cl^(−)浓度的增加则显著抑制Sb(III)的还原,因此,沉积物中的As含量随电解液中HCl浓度的上升而逐渐增加,同时,产物的结构从晶态转变为非晶态。当As含量为24.55%~33.75%(质量分数),产物为AsSb晶态与非晶态的混合物。电解温度对沉积物的组成影响较小,但AsSb合金的结构随温度的降低从晶态转变为非晶态。

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.