Activated Carbon–TiO₂ Photoanodes for Enhanced Performance of Celosia Dye-sensitized Solar Cells
J. Environ. Nanotechnol., Volume 15, No 3 (September 2026) pp. 869-881
Abstract
Aiming to improve the performance of Celosia flower dye-sensitized solar cells (DSSCs), this study focuses on the development of activated carbon–TiO₂ heterostructured photoanodes to enhance both light harvesting efficiency and charge transport characteristics. Activated carbon (AC) was produced from coconut husk biomass by carbonization and characterized using XRD, FESEM, and EDAX to determine its crystalline structure, morphology, and elemental composition. The prepared AC was then incorporated into a TiO₂ matrix to form an AC–TiO₂ hetero structured photoanode, which was subsequently deposited onto a fluorine-doped tin oxide (FTO) substrate. Celosia flower (cockscomb) extract, owing to its high pigment content and environmental sustainability, was used as a natural dye sensitizer for fabricating DSSCs comprising the AC–TiO₂ photoanode, dye sensitizer, electrolyte, and counter electrode. Compared with DSSCs based solely on TiO₂, the DSSCs based on AC–TiO₂ demonstrated improved photoelectrochemical properties, including increased surface area, enhanced electron mobility, and reduced charge recombination, along with an approximately 20% increase in photovoltaic conversion efficiency. AC enabled an approximately 15% reduction in dye loading while maintaining comparable photovoltaic performance. These findings suggest that AC exerts a synergistic effect by improving light absorption and charge transfer within the DSSC. The development of an AC–TiO₂ hetero structured photoanode provides a low-cost and sustainable approach for enhancing the performance of natural dye-based solar cells. Future studies could include optimization of AC loading, development and characterization of alternative biomass-derived carbon materials, investigation of alternative natural dye sensitizers, and evaluation of long-term stability and large-scale manufacturing processes for sustainable solar energy systems.
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Reference
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