Supramolecular strategies in artificial photosynthesis

Artificial photosynthesis is a major scientific endeavor aimed at converting solar power into a chemical fuel as a viable approach to sustainable energy production and storage. Photosynthesis requires three fundamental actions performed in order; light harvesting, charge-separation and redox catalysis. These actions span different timescales and require the integration of functional architectures developed in different fields of study. The development of artificial photosynthetic devices is therefore inherently complex and requires an interdisciplinary approach. Supramolecular chemistry has evolved to a mature scientific field in which programmed molecular components form larger functional structures by self-assembly processes. Supramolecular chemistry could provide important tools in preparing, integrating and optimizing artificial photosynthetic devices as it allows precise control over molecular components within such a device. This is illustrated in this perspective by discussing state-of-the-art devices and the current limiting factors - such as recombination and low stability of reactive intermediates - and providing exemplary supramolecular approaches to alleviate some of those problems. Inspiring supramolecular solutions such as those discussed herein will incite expansion of the supramolecular toolbox, which eventually may be needed for the development of applied artificial photosynthesis.