ELECTROOXIDATION OF FORMIC-ACID ON PALLADIUM ELECTRODEPOSITS IN THE SULFURIC-ACID ELECTROLYTES

Kinetic parameters of the HCOOH electrooxidation on Pd electrodeposits (average Tafel slopes, pH dependence of the reaction rate, and reacti on order) are determined under steady-state conditions. A reaction sch eme is put forward that explains, to the first approximation, the expe rimental data. It is assumed that the catalytic reaction of dehydrogen ation of adsorbed HCOOH molecules is the slow stage of the steady-stat e process. It is shown that the structure of electrodeposited Pd affec ts the HCOOH oxidation kinetics. For example, strongly chemisorbed pro ducts accumulated on the Pd surface deposited from sulfuric acid solut ions and were absent on PD deposited from hydrochloric acid solutions.