Catalytic oxidation of hydrogen over platinum

Abstract

The oxidation of hydrogen on platinum has been studied using a microcalorimetric technique. The reaction takes place by two mechanisms depending on whether the surface is in an oxidised or reduced state. On the reduced surface, hydrogen is dissociatively adsorbed and competes with adsorbed molecular oxygen for adsorption sites. The reaction rate is higher on the oxidised surface where hydrogen molecules are weakly adsorbed and react with strongly adsorbed oxygen.