Hybrid bio-photo-electro-chemical cells for solar water splitting

• Published in: Nature communications Vol. 7; no. 1; p. 12552
• Main Authors: Pinhassi, Roy I, Kallmann, Dan, Saper, Gadiel, Dotan, Hen, Linkov, Artyom, Kay, Asaf, Liveanu, Varda, Schuster, Gadi, Adir, Noam, Rothschild, Avner
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 23.08.2016; Nature Portfolio
• Subjects: Algorithms; Alternative energy sources; Cyanobacteria; Energy consumption; Hydrogen; Hydrogen - metabolism; Land area; Oxidation; Oxidation-Reduction - radiation effects; Oxygen - metabolism; Photochemical Processes; Photosynthesis; Photosynthesis - radiation effects; Photovoltaic cells; Solar Energy; Spinacia oleracea - metabolism; Spinacia oleracea - radiation effects; Sunlight; Thylakoids - metabolism; Thylakoids - radiation effects; Water - metabolism; Israel
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms12552

Photoelectrochemical water splitting uses solar power to decompose water to hydrogen and oxygen. Here we show how the photocatalytic activity of thylakoid membranes leads to overall water splitting in a bio-photo-electro-chemical (BPEC) cell via a simple process. Thylakoids extracted from spinach are introduced into a BPEC cell containing buffer solution with ferricyanide. Upon solar-simulated illumination, water oxidation takes place and electrons are shuttled by the ferri/ferrocyanide redox couple from the thylakoids to a transparent electrode serving as the anode, yielding a photocurrent density of 0.5 mA cm(-2). Hydrogen evolution occurs at the cathode at a bias as low as 0.8 V. A tandem cell comprising the BPEC cell and a Si photovoltaic module achieves overall water splitting with solar to hydrogen efficiency of 0.3%. These results demonstrate the promise of combining natural photosynthetic membranes and man-made photovoltaic cells in order to convert solar power into hydrogen fuel.