Studies on the Spectrophotometric Determination, Electrochemical Behavior of Heavy Lanthanide ions in Nonaqueous System and Heavy Chelates Complexes with Bidendate Ligands () Electrochemical Behavior of Heavy Lanthanide Ions in Acetonitrile

摘要

Voltammetric behavior of heavy lanthanide ions has been investigated by the DC, DPP and CV in acetonitrile solution. The reduction of Gd3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+ and Lu3+ proceed by three-electron change to the metallic state with totally irreversibility in 0.1M tetraethylammonium perchlorate. However, the reduction of Yb(￥2) proceeds in two steps (Yb3+ ￡? e- ?? Yb2+ and Yb2+ ￡? 2e- ?? Yb0). The first reduction of Yb(￥2) showed quasi reversible behavior, but the second reduction was irreversible in cyclic voltammetry. The cathodic peak current showed adsorptive properties in high concentration with lower sweep rate. The electroreduction of heavy lanthanides in water-acetonitrile mixture has been studied. In water-acetonitrile mixture, the negative shift of the peak potential and the decrease peak current were observed increasing water concentration. Also the Yb(￥2) reduction to Yb(￥2) has been deviated from quasi-reversible character with increase water amount. These results drive from the high solvation abilities of water which has high donor number.