Performance of dye-sensitized solar cells based on varied dye thermal extraction

Dye-sensitized solar cell (DSSC) was fabricated with seven natural dye extract; Rosella, Bawang Sabrang, Cherry Barbados, Mulberry, Ardisia, Oxalis Triangularis, and Harum Manis mango. The DSSCs are fabricated and characterized to obtain the performances of each dye under variation of extracting temperature. The dyes are extracted into water and ethanol solution at different temperatures (25⁰C, 40⁰C, 50⁰C, 75⁰C and 100⁰C) anchored to a titanium dioxide layer, TiO₂. The DSSCs is characterized and analyzed to obtain the efficiency and the difference in the absorption spectrum for the extracting solvents. Based on the detailed observation in this paper, dyes extracted into ethanol solvent produce a higher efficiency DSSCs vis-à-vis the water solvent dyes. The absorption spectrum of dyes in water shows highest peaks for Mulberry and Oxalis Triangularis dyes at about 550nm. For the dye extracted in ethanol solvent, the highest absorption peaks at 580nm, 530nm and 450nm were observed for Rosella, Mulberry and Oxalis Triangularis dyes. This paper reports on the highest efficiency of about 8.85% for Rosella dye extracted at 25°C in water. As for extracting temperature at 40°C, the best dye performance is Oxalis Triangularis with an efficiency of 1.49% and at 50°C is Ardisia with 4.34%. While for temperatures of 75°C and 100°C, Oxalis Triangularis and Harum Manis have efficiency about 2.07% and 1.87% respectively. Meanwhile the efficiency in ethanol solvent for Rosella at extracting temperature of 25°C and 100°C shows efficiency of 11.25% and 7.8% respectively. At an extracting temperature of 40°C, Cherry Barbados resulted efficiency 1.99%, followed by Ardisia and Harum Manis, which achieved an efficiency about 1.36% and 2.55%, separately. The systemic variation of temperature in different extracting solvent showed that performance of al- organic dyes involved can be manipulated. This is crucial, especially in the specific application of wavelength sensitive solar cells. This paper reveals detailed optimized fabrication process with different extracting temperatures for various organic dye based solar cells as well as proposal of causes for their myriad performances.