Biophotovoltaic Systems Based on Photosynthetic Complexes

Abstract Biophotovoltaics is a young and dynamic field of green nanotechnology which utilizes photosynthetic organisms, such as cyanobacteria and algae, their photosynthetically active biological membranes, or the components of the photosynthetic apparatus to harness solar energy and convert it into electricity and solar fuels. The attractiveness of this approach stems from the use of “living solar cells” or their photochemically active components which are capable of self-assembly and self-renewing, and which have been optimized for over 3.5 billion years of evolution for efficient solar energy conversion. It is envisaged that biophotovoltaics, when optimized, will provide a viable technological alternative to costly synthetic solar-converting technologies based on the classical photovoltaics. Recently, much effort has been put into rational combining of the photoactive cells or their light-converting biocomponents with properly nanostructured, energetically compatible electrode materials to yield biophotoelectrodes, complete solar cells, and photoelectrochemical devices of significantly improved power conversion efficiencies. Here, we describe the recent advances in biophotovoltaics with emphasis on the photosystem-based devices, their operational mode, as well as the materials and nanostructuring used to achieve the highest power conversion efficiencies. We focus on the photosystem I-based systems, since much of the advanced mechanistic investigation was devoted to this macromolecular machine due its high quantum efficiency, relative stability, and easiness of structural modification for its specific nanostructuring within the solar-converting devices.