Optical Interactions in Bio-Electricity Generation from Photosynthesis in Microfluidic Micro-Photosynthetic Power Cells

Within the realm of renewable energy sources, biological-based power systems have emerged as pivotal players particularly suited for low- and ultra-low-power applications. Unlike microbial fuel cells (MFCs), which invariably rely on external carbon feedstock, micro-photosynthetic cells (mu PSCs) exhibit a unique feature by operating independently of organic fuel. They harness the principles of photosynthesis and respiration to generate electricity in both illuminated and dark settings through water-splitting reactions. Here, we present a viable, easy, and cost-effective method to fabricate mu PSCs. We meticulously examined the performance of a fabricated mu PSC under varying illuminations and even in the absence of light. With an electrode surface area spanning 4.84 cm2, the mu PSC achieved its peak power output of 200.6 mu W when exposed to an illumination of 2 mu molm-2s-1 (equivalent to 147 lux). Of the three light intensities studied, 2 mu molm-2s-1, 8 mu molm-2s-1 (595 lux), and 20 mu molm-2s-1 (1500 lux), the mu PSC exhibited its optimal performance at a light intensity of 2 mu molm-2s-1, establishing this as the ideal operational illumination. Furthermore, intermittent toggling of the illumination had no discernible impact on the mu PSC's performance. However, subjecting it to a dark environment for 30 min resulted in a reduction in the maximum power to 81 mu W, marking a significant 119% decrease when compared to the peak power output achieved under 2 mu molm-2s-1 illumination.