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Developing a scalable artificial photosynthesis technology through nanomaterials by design

Nature Nanotechnology volume 11, pages 10101019 (2016) | Download Citation

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Abstract

An artificial photosynthetic system that directly produces fuels from sunlight could provide an approach to scalable energy storage and a technology for the carbon-neutral production of high-energy-density transportation fuels. A variety of designs are currently being explored to create a viable artificial photosynthetic system, and the most technologically advanced systems are based on semiconducting photoelectrodes. Here, I discuss the development of an approach that is based on an architecture, first conceived around a decade ago, that combines arrays of semiconducting microwires with flexible polymeric membranes. I highlight the key steps that have been taken towards delivering a fully functional solar fuels generator, which have exploited advances in nanotechnology at all hierarchical levels of device construction, and include the discovery of earth-abundant electrocatalysts for fuel formation and materials for the stabilization of light absorbers. Finally, I consider the remaining scientific and engineering challenges facing the fulfilment of an artificial photosynthetic system that is simultaneously safe, robust, efficient and scalable.

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Acknowledgements

The work described herein was enabled by support from the National Science Foundation Center for Chemical Innovation, the Department of Energy Office of Basic Energy Sciences, the Air Force Office of Scientific Research, the Department of Energy through the Joint Center for Artificial Photosynthesis, and the Gordon and Betty Moore Foundation, as acknowledged in the individual publications referenced herein, as well as for partial salary support for N.S.L. that enabled the preparation of this manuscript. M. McDowell and K. Papadantonakis are acknowledged for assistance in preparation of this manuscript. A special acknowledgment is extended to the enthusiastic, talented and dedicated cohort of graduate students, post-doctoral fellows, collaborators and colleagues for their extraordinary, enabling contributions to this research effort, as acknowledged in the publications described and referenced herein.

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  1. Division of Chemistry and Chemical Engineering, Beckman Institute and Kavli Nanoscience Institute, California Institute of Technology, Pasadena, California 91125, USA

    • Nathan S. Lewis

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The author declares no competing financial interests.

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Correspondence to Nathan S. Lewis.

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https://doi.org/10.1038/nnano.2016.194

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