ELECTROCATALYTIC REDUCTION OF CARBON-DIOXIDE BY SUBSTITUTED PYRIDINE AND PYRAZOLE COMPLEXES OF PALLADIUM

A series of [PdCl(2)L(2)] complexes (L=substituted pyridine and pyrazo le) has been tried as an electrocatalyst for the reduction of CO2 in a cetonitrile (AN) containing 0.1M tetraethylammonium perchlorate (TEAP) at glassy carbon or Pt electrodes. The complexes working as the catal yst were [PdCl(2)L(2)] (L=Pyrazole (Pyra), 4-Methylpyridine (4-Mpy) an d 3-methylpyrazole (3-Mpyra)) at an applied potential of -1.10V vs Ag/ 10mM Ag+ and the reduction products were formic acid and H-2 with no C O. The current efficiency for the formation of formic acid were 10, 20 and 10.2% for Pd complexes of Pyra, 4-Mpy and 3-Mpyra, respectively. The current efficiency for the hydrogen evolution were 31-54%, and the source of the formate proton and hydrogen was from the added water (4 % by volume). Copyright (C) 1996 Elsevier Science Ltd.