The electrochemical behavior of CoL (cobalt Schiff base complex) has been studied in ionic liquids. Its catalytic activity towards the reduction of PhCH₂Cl and the reaction between PhCH₂Cl and CO₂ has also been investigated. CoL shows a diffusion controlled one-electron reversible peak couple in ionic liquids. The electrochemical behavior shows that the peak potential will not be influenced by the Schiff base ligand and the anion of the ionic liquids. CoL could catalyze the reduction of PhCH₂Cl by the voltammograms. The mechanism involves a one-electron reduction and a chemical reaction followed by another one-electron reduction. And this system could also catalyze the reaction between PhCH₂Cl and CO₂. Controlled-potential electrolysis led to (PhCH₂)₂CO, indicating that CO₂ can be fixed in ionic liquids by the catalysis of CoL.

Key words: ionic liquid, electrocatalysis, benzyl chloride, carbon dioxide