Supercapacitive Biosolar Cell Based on

Nanoimprinted Gold Electrodes

Photobioelectrical systems are arising green energy producing technologies, where photosynthetic biomaterials in combination with an electronic conductor are used to convert solar energy into electrical energy [1]. Various photosynthetic biological species, both of subcellular and cellular character, have being employed to transform solar energy into the electrical energy, such as photosynthetic reaction centers (PSI and PSII), thylakoid membranes, chloroplasts, cyanobacteria or green algae [1, 2], having their advantages and disadvantages depending on the particular application. A key challenge in the design of photobioelectrodes is to boost the electrical communication between biocatalysts and electrode surfaces. However, nanoimprint lithography (NIL) approach, which assures well-controlled nanostructured geometry of electrodes [3], has not been used for photosynthetic electricity production so far, though, other nanostructuration methods have been already exploited [4, 5]. Nano-imprinted electrodes allow efficient accommodation of photo-biocatalysts inside the three-dimensional nanostructures [4] ensuring by that enhanced contact area with the electrode surface and facile electron transfer. Therefore, in this work we introduce a novel design of dual feature photobioanode based on nanoimprinted gold electrodes modified with thylakoids for photosynthetic electricity production in combination with a capacitive part made of a planar gold substrate modified with conductive polymer for enhancement of charge storing capabilities, taking advantages of the earlier disclosed principle of simultaneous energy conversion and storage in a singular module [6, 7], and, finally, combine it with NIL based biocathode to form a supercapacitive biosolar cell.

References:

[1] Hasan, K., et al., Photobioelectrocatalysis of Intact Chloroplasts for Solar Energy Conversion. ACS Catal., 2017. 7(4): p. 2257-2265.

[2] McCormick, A.J., et al., Biophotovoltaics: oxygenic photosynthetic organisms in the world of bioelectrochemical systems. Energy Environ. Sci., 2015. 8(4): p. 1092-1109.

[3] Pankratov, D., et al., Scalable, high performance, enzymatic cathodes based on nanoimprint lithography. Beilstein J. Nanotechnol., 2015. 6: p. 1377-1384.

[4] Ryu, D., et al., Thylakoid-Deposited Micro-Pillar Electrodes for Enhanced Direct Extraction of Photosynthetic Electrons. Nanomaterials (Basel), 2018. 8(4).

[5] Patole, S., et al., Interference lithographic nanopatterning of plant and bacterial light-harvesting complexes on gold substrates. Interface Focus, 2015. 5(4): p. 20150005.

[6] Pankratova, G., et al., Supercapacitive Photo-Bioanodes and Biosolar Cells: A Novel Approach for Solar Energy Harnessing. Adv. Energy Mater., 2017. 7(12): p. n/a.

[7] Gonzalez-Arribas, E., et al., Solar biosupercapacitor. Electrochem. Commun. 2017. 74: 9