Tailored Assembly of Molecular Water Oxidation Catalysts onto Photoelectrodes for Artificial Photosynthesis

Abstract

Solar-to-chemical energy conversion, or so-called artificial photosynthesis, is a promising technology enabling sustainable production and use of various chemical compounds such as H-2, CO, CH4, HCOOH, CH3OH, and NH3. For practical applications, it is necessary to improve the interfacial properties of light-harvesting semiconductors through modification with proper electrocatalysts, by trying to overcome their intrinsic limitations such as rapid recombination, sluggish reaction kinetics, and photocorrosion. Compared to their heterogeneous counterparts, molecular electrocatalysts have a higher catalytic activity and more flexibility in their design/synthesis and integration with semiconducting materials. In this article, we review recent efforts on the tailored assembly of molecular electrocatalysts to address the above issues for artificial photosynthesis, especially those for oxygen evolution reactions on semiconductor photoelectrodes for photoelectrochemical water oxidation. One can expect that the strategies and methods developed for the tailored assembly and integration of molecular electrocatalysts on water oxidation photoanodes can provide insights for the design and fabrication of various forms of photosynthetic devices due to the similarity between their underlying principles.