An Alternative Approach for the Coffee Husk Dye-Sensitized Solar Cell

Abstract

INTRODUCTION

Sustainable energy forms became the focus of attention now as issues for non-renewable energy sources increases. To address these problems, sustainable sources such as solar power are established. In order to harness the solar energy, a type of solar cell called dye-sensitized solar cell (DSSC) that utilizes organic dyes such as coffee husk dye was developed. It is easy to make, but the problem lies with the availability of materials. This study attempts to increase the electrical output of the DSSC by using alternative materials.

METHODS

Experimental method of research was used in this study. Coffee husks was immersed in water and ethanol to extract the anthocyanin pigment. The conductive glass was made using SnCl2 (stannous chloride)and (NH4) HF2 (ammonium bifluoride) solution. The anode was made by applying a TiO2 (titanium dioxide) paste made from TiO2 and vinegar in three conductive glasses. It was dried and immersed in the extracted dye. The cathode was made by rubbing a pencil lead in another conductive glass. A lugol's iodine electrolyte solution was sandwiched between the anode and cathode. The fabricated solar cell was tested using a digital multimeter.

RESULTS

The fabricated conductive glass demonstrated a resistance with a value of 4.48kΩ. In direct sunlight, the average voltage produced is 423.6 mV. The power output is 3.27E-03 mW/cm2. In diffused sunlight, the average voltage produced is 406.7 mV. The power output is 3.02E-03 mW/cm2 In artificial light, the average voltage produced is 396.2 mV. The power output is 2.86E-03 mW/cm2. Using the obtained and calculated data, the solar energy to electrical energy conversion efficiency is 0.02023%.

DISCUSSIONS

The study showed that the harvested solar energy can be converted into electricity using a dye-sensitized solar cell that utilized alternative materials. It was shown that the power output is comparable to the DSSCs fabricated in the laboratories. Since the voltage does not depend on the resistance, it can be inferred that the improvement of the voltage output came from the lugol's iodine electrolyte and the graphite catalyst. In order to improve the power output and efficiency, it is recommended to use a readily fabricated conductive glass that has a low resistance.