Tuesday, May 20, 2008 - 1:30 PM
Medical Arts Building, Rm M-146 (Queensborough Community College)
441

Computational Studies of Artificial Photosynthesis

James T. Muckerman and Etsuko Fujita. Brookhaven National Laboratory, Upton, NY

Artificial photosynthesis is an area of research that seeks to replicate the natural process of photosynthesis that coverts sunlight, water and carbon dioxide into carbohydrates and oxygen. The visible-light driven splitting of water into hydrogen and oxygen and even the targeting of methanol as the product of CO2 reduction are sometimes included in the definition. There are two distinct approaches to realizing the goal of artificial photosynthesis: structural models vs. functional models of the natural systems. We are pursuing theoretical and experimental studies of functional models as exemplified in recent work on hydrogenase-inspired catalysts for H2 oxidation and proton reduction. But this is only one aspect of the complicated set of processes that replicate natural photosynthesis. We will present examples from our recent work in a number of aspects of artificial photosynthesis. We will discuss how the function of the chlorophyll arrays in plants might be replaced with a suitable band-gap-narrowed semiconductor photoanode in a photoelectrochemical cell, possibly with the aid of a molecular multi-electron water oxidation catalyst. We will also describe how the role of a reduced nicotinamide adenine dinucleotide phosphate (NADPH) co-factor as the carrier and donor of two electrons and a proton might be replaced by a photogenerated hydride donor to carry out the function of Photosystem I.