The reduction of carbon dioxide at illuminated p-type semiconductor electrodes in nonaqueous media

✍ Scribed by I. Taniguchi; B. Aurian-Blajeni; J.O'M. Bockris

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 837 KB
• Volume: 29
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(84)87137-6

✦ Synopsis

The photo-electrochemical reduction of CO2 has been examined on a number of p-type semiconductors. The (I 00) plane of CdTe gave the best results: CO was the main product. The most used solution was DMF with 5 oA water. The onset potential was ca. -1.00 V US see. Reaction order with respect to CO1 was one. The faradaic efficiency for CO formation was > 80 % in DMF solutions containing water up to 25 7" and currents were stable for 24h. Tetraalkylammonium salts were suitable electrolytes. DMSO and PC were also useful solvents. Increase of teMpcXatUre shifted the onset potential to more negative potentials. In and Pb coatings reduced and Pt, Ru and Ni increased co-reduction of H,O to Hz. Limiting photocurrents were proportional to light intensity. Taking into account the CO dissolved in the solutions increases the current efficiency to 90 %. CO2 + e -*COT, followed by CO, +CO,+e-CO+CO:and CO; +2H* +e*CO+H20,