Evaluation of Solar Conversion Efficiency in Dye-sensitized Solar Cells Using Natural Dyes Extracted from <i>Alpinia purpurata</i> and <i>Alstroemeria</i> Flower Petals as Novel Photosensitizers

Abstract

Herein, we evaluate the conversion efficiency of dye-sensitized solar cells (DSSCs) photosensitized using two different natural dyes extracted from Alpinia purpurata and Alstroemeria flower petals. The appreciable absorption capacity of the extracts in the visible light region was examined through absorption spectroscopy. The functional groups of the corresponding pigments were identified through Fourier transform spectroscopy (FTIR) technique thus indicating the presence of cyanidin 3-glycosides and piperine in the flowers of Alstroemeria and Alpinia purpurata. The extracted dyes were immobilized on TiO2 on transparent conducting FTO glass, which were used as photoanode. The dye-coated TiO2 photoanode, pt photocathode and iodide/triiodide redox electrolyte assembled into a cell module was illuminated by a light source intensity 100 mW/cm2 to measure the photovoltaic conversion efficiency of DSSCs. The TiO2 anode and Pt counter electrode surface roughness and morphological studies were evaluated using atomic force microscope (AFM) and field emission scanning electron microscopy (FESEM), respectively. Through the photoelectric characterizations, it was promising to verify that the solar conversion efficiency was calculated with the photovoltaic cell sensitized by Alstroemeria and Alpinia purpurata. This was achieved with a yield (η) of 1.74% and 0.65%, with an open-circuit voltage (Voc) of 0.39 and 0.53 V, short-circuit current density (Jsc) of 2.04 and 0.49 mA/cm2, fill factor (FF) of 0.35 and 0.40, and Pmax of 0.280 and 0.100 mW/cm2, respectively. The results are promising and demonstrate the importance of the search for new natural dyes to be used in organic solar cells for the development of devices that generate electricity in a sustainable way.

Keywords

• dye-sensitized solar cells
• natural dyes
• photosensitizers
• photovoltaics
• renewable energy