Artificial Leaf Technology Advancing

Beyond photovoltaics, solar driven hydrogen extraction has been coming on fast.  (E.g., this or this.)  the idea is simple: input sun, air, and water; output hydrogen or other useful chemicals.

This concept is sometimes called ‘artificial photosynthesis”, though that’s a bit misleading because the processes are different.  And, by extension, there are a number of light and thin devices that are tagged “artificial leaves”.

The attraction is obvious, especially for marine applications.  “Leaves” float on water in the sunlight, and out comes H2 that can be used as fuel.  Problem solved!

This summer, researchers at Cambridge University report on a new, light weight artificial leaf that generates hydrogen or syngas [1].  The basic principle has been under development for more than a decad, but the new research addresses the useability [2].  The goal is to match the size and weight of a natural leaf, with similar or better productivity.

The details are out of my specialty area, but if I understand correctly, the units can produce a couple of grams of H2 per hour per gram of device.  So, covering a swimming pool sized area of water might produce a kilogram or two of hydrogen each day (I think).  This could be enough to fuel a boat or vehicle for a day. 

Which would be cool.

This technology depends on the catalyst used, so productivity could potentially improve, possibly a lot.

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1. Virgil Andrei, Geani M. Ucoski, Chanon Pornrungroj, Chawit Uswachoke, Qian Wang, Demetra S. Achilleos, Hatice Kasap, Katarzyna P. Sokol, Robert A. Jagt, Haijiao Lu, Takashi Lawson, Andreas Wagner, Sebastian D. Pike, Dominic S. Wright, Robert L. Z. Hoye, Judith L. MacManus-Driscoll, Hannah J. Joyce, Richard H. Friend, and Erwin Reisner, Floating perovskite-BiVO4 devices for scalable solar fuel production. Nature, 608 (7923):518-522, 2022/08/01 2022. https://doi.org/10.1038/s41586-022-04978-6
2. Prachi Patel, Floating Artificial Leaf Turns CO2 Into Fuel, in IEEE Spectrum – Energy, August 25, 2022. https://spectrum.ieee.org/artificial-leaf-hydrogen-syngas