Photoelectrocatalyst Discovery Using High-Throughput Methods and Combinatorial Chemistry

Abstract

In spite of decades of work by hundreds of talented researchers a cost-effective means of transforming the sun's energy into electricity, or, storable fuels or chemicals has not been found. Of the known semiconductors that might be used in photoelectrochemical processes none have been shown to be cost effective; however, there are an enormous number of formulations that could be created from earth abundant non-toxic elements, and only a tiny fraction have been synthesized and studied. Unfortunately, we do not have the basic knowledge or theory to predict in advance the existence of a suitable material system or what the composition should be. Combinatorial chemistry is the synthesis and screening of large numbers of different materials from different combinations of chemical variables in a systematic and deliberate manner to explore their composition–structural-property relationships and discover, by induction, an otherwise unpredictable material with specific desirable properties. In the absence of a thorough a prior understanding of the many interdependent properties and relationships between components, the components are combined in a large number of different ways and from observations of specific properties of the different combinations the fundamental interdependent relationships are inductively determined. High-throughput experimentation methods using robotics and computers allows the use of combinatorial methods at high speed to increase the rate of discovery and understanding of complex materials.