A tandem solar biofuel cell: Harnessing energy from light and biofuels
Angew. chem; int. ed. engl
We report on a photobioelectrochemical fuel cell consisting of a glucose oxidase modified BiFeO 3 photobiocathode and a quantum dot sensitized inverse opal TiO 2 photobioanode linked to FAD glucose dehydrogenase via a redox polymer. Both photobioelectrodes are driven by enzymatic glucose conversion. Whereas the photobioanode can collect electrons from sugar oxidation at rather low potential, the photobiocathode shows reduction currents at rather high potential. The electrodes can be arranged sandwich-like due to the semi-transparent nature of BiFeO 3 , which also guarantees a simultaneous excitation of the photobioanode when illuminated via the cathode side. This tandem cell can generate electricity under illumination and in the presence of glucose and provides an exceptionally high OCV of about 1 V. The developed semi-artificial system has significant implications on the integration of biocatalysts in photoactive entities for bioenergetic purposes and opens a new way for the generation of electricity from sun light and (bio-)fuels.