Evolution of reaction center mimics to systems capable of generating solar fuel

Abstract

Capturing and converting solar energy via artificial photosynthesis offers an ideal way to limit society's dependence on fossil fuel and its myriad consequences. The development and study of molecular artificial photosynthetic reactions centers and antenna complexes and the combination of these constructs with catalysts to drive the photochemical production of a fuel helps to build the understanding needed for development of future scalable technologies. This review focuses on the study of molecular complexes, design of which is inspired by the components of natural photosynthesis, and covers research from early triad reaction centers developed by the group of Gust, Moore, and Moore to recent photoelectrochemical systems capable of using light to convert water to oxygen and hydrogen.

Recent progress in homogeneous multielectron transfer photocatalysis and artificial photosynthetic solar energy conversion

“…While modelling important functions of photosynthetic reaction centers such as light-absorption across the visible spectrum, excitation energy transfer and subsequent generation of charge separated states with high quantum yields has already reached a considerable level within the last decades [18], the development of complete artificial photosynthetic model systems capable of converting light energy into solar fuels still remains a major challenge [18,19]. One of the most serious problems encountered is to couple photoinduced charge separated states to functional building blocks acting as efficient catalysts for multielectron transfer (MET) and proton coupled electron transfer (PCET) steps, which are required to achieve permanent energy storage in sufficiently stable chemical bonds (Scheme 1).…”

Quantum modeling of ultrafast photoinduced charge separation

“…They have smaller dimensions than natural reaction centers, and therefore a small CT exciton radius and limited delocalization extension. They may be considered as models for nano-sized photovoltaic devices, and synthesis protocols exist for testing them as potential light-harvesters, artificial reaction centers, or solar fuels generators [49].…”

Biomimetic Complexes for Production of Dihydrogen and Reduction of CO2

“…This understanding of natural photosynthesis and attempts to reengineer it have served as inspiration for artificial photosynthetic systems [124]; see Fig. 15 for a schematic view of the components and functional requirements for an artificial photosynthetic system.…”

“…15 for a schematic view of the components and functional requirements for an artificial photosynthetic system. Although artificial constructs capable of emulating certain aspects of photosynthesis, such as light-driven generation of a long-lived chargeseparated state, have been described [124][125][126][127], developing complete systems for efficient utilization of light energy to produce fuel remains a significant challenge. More than a hundred molecular catalysts for electrocatalytic proton reduction have been described; in contrast, relatively few molecular systems for photocatalytic hydrogen production have been reported [128].…”