Hydrogen and oxygen evolution from water using Ag and AgCl colloids

Photolysis of silver chloride in aqueous medium resulted in the formation o f silver clusters and the evolution of oxygen from water. These silver clus ters, when photooxidized in the presence of aqueous potassium iodide soluti on resulted in hydrogen being evolved from water. Preliminary laser investi gations were carried out to confirm the proposed mechanism. The photooxidat ion process may possibly be applied to recycle silver from exposed photogra phic film wastes and as a means of converting solar energy, with simultaneo us evolution of hydrogen. (C) 1999 International Association for Hydrogen E nergy. Published by Elsevier Science Ltd. All rights reserved.