10th U6+ Consortium of African Universities International Conference

As global energy demand accelerates, sustainable green energy solutions are a multifaceted priority. According to Michael Grätzel, solar energy incident on Earth far exceeds global daily requirements; however, capturing this energy efficiently and sustainably remains a challenge. While silicon-based photovoltaics dominate the market, Dye-Sensitized Solar Cells (DSSCs) offer a compelling, low-cost, biodegradable alternative. A primary bottleneck in DSSC performance is the narrow spectral response of individual natural dyes compared to synthetic ruthenium complexes. This study investigates the synergistic potential of four locally sourced botanical sensitizers: Bloodleaf (Iresine herbstii), Black Jack (Bidens pilosa), and Potato Tree berries (Solanum erianthum). Natural pigments were isolated via solvent extraction using ethanol and methanol. Optical characterization was performed via UV-Vis Spectrophotometry to evaluate absorbance and Light Harvesting Efficiency (LHE) while FTIR was used to identify critical anchoring groups (carboxyl and hydroxyl units). Initial data indicates that Bloodleaf and Potato Tree berries provide strong anthocyanin-based absorption in the 500–680 nm region, while Black Jack response spans 400–500 nm range. These experimental parameters serve as the foundation for numerical modeling using the Transfer Matrix Method (TMM) to optimize a panchromatic cocktail. It is anticipated that the optimized blend will bridge individual spectral gaps, yielding superior short-circuit current density and power conversion efficiency. This research demonstrates that strategic combinations of invasive and common plant species can effectively mimic expensive synthetic sensitizers, supporting the shift toward fully organic, biodegradable solar technology.