Electrochemical investigation of thin films of cobalt phthalocyanine and cobalt-4,4′,4″,4′″-tetracarboxyphthalocyanine and the reduction of carbon monoxide, formic acid and formaldehyde mediated by the Co(I) complexes

✍ Scribed by Kousuke Kusuda; Ryuichi Ishihara; Hidemasa Yamaguchi; Ikuichiro Izumi

• Publisher: Elsevier Science
• Year: 1986
• Tongue: English
• Weight: 765 KB
• Volume: 31
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(86)87032-3

✦ Synopsis

Cyclic voltammetric investigations of thin films of cobalt(I1) phthalocyanine(1) and cobalt(II)-4,4',4",4"-tetracarboxyphthalocyanine(2)

in Nz-saturated 1 M sulfuric acid solution revealed that both compounds gave irreversibly semi-stable reduction products, R-l and R-2, at around -0.7OV vs see. Reductions of CO, formaldehyde and formic acid by R-l or R-2 were conducted with vibrating carbon fiber electrode (cfe) modified with 1 or 2. Products of the reduction of CO were mainly formaldehyde and a small amount of methanol. In the reduction of CO, R-2/cfe was ca 17 times more efficient than R-l/cfe, which was however more efficient than the former in the reduction of formaldehyde. Reduction of formic acid by R-2 and R-l seemed to be difficult under the conditions. Reduction of CO on the 2/cfe polarized with rectangular potential pulse (-0.659V for 5s and 0.2OV vs Ag/AgCl for 85s) produced nearly quantitative yield of formaldehyde and small amount of methanol.