Sustainable electricity generation from photo-bioelectrochemical cell based on carbon nanotubes and chlorophyll anode

This study developed a photo-bioelectrochemical cell based on CNT-chlorophylls to produce photocurrent by lighting electrodes in water-based solutions. The extracted chlorophyll from Chlorella vulgaris microalgae was used to modify carbon nanotube (CNT) as a photo-biocatalyst offering low cost and abundant resources. Furthermore, it is an excellent choice as an alternative bioenergy feedstock compared to lignocellulosic material. The physical interactions between the hydrophobic chlorophyll tail and the hydrophobic nature of the CNT induce the hydrophobic interaction. Subsequently, the CNT/chlorophyll photo-biocatalyst ink was deposited on the carbon felt and used as a photo-anode in photo-bioelectrochemical cells. With the introduction of light, the CNT/chlorophyll photo-biocatalyst is capable of generating 6 times higher photo-currents than in the dark. Also, the maximum power density produced by this device was about 9.48 mW/m2, which is eleven times greater than the CNT control. Therefore, this analysis is a promising system of generating relatively large amounts of photobioelectrochemical current by incorporating biological renewable material of chlorophyll derived from Chlorella vulgaris.