Fabrication of Dye-Sensitized Solar Cell using Natural Dyes from Lawsonia Inermis (Henna), Mangifera Indica (Mango), and Terminalia Catappa (Tropical Almond) Leaves with Polyaniline/Graphite as A Counter Electrode

This study used extracts from Lawsonia inermis L. (Henna), Terminalia catappa L. (Tropical Almond), and L. (Mango) as for dye-sensitized solar .
The mango and tropical almond extracts were extracted using while the henna extract was gotten using alkaline extraction.

The choice of extraction solvent was based on the ability to permeate the plant membranes and toxicity of the solvent. This study used TiO₂ as the semiconductor material, iodide/triiodide as the redox electrolyte, and PANI/Graphite couple as the counter electrode.

From the results gotten from the study, the henna extract produced the highest voltage and current when tested under projector light (57.6mV and 0.018mA) and sunlight (0.188V and 0.282mA).

In contrast, the mango extract produced the lowest results under the same conditions (no electricity under projector light; 0.892mV and 0.0164mA under sunlight).

Introduction

Background of Study

Electricity is a form of energy that improves the quality of human life to a great extent. Its demand has increased exponentially over the years thereby causing a strain on its sources.

Currently, the major source of electricity is burning of fossil fuels. The usage of fossil fuels as a source of electricity results in the emission of greenhouse gases such as carbon dioxide (CO₂) and methane (CH₄).

These gases are very harmful to the environment as they contribute to global warming. Furthermore, during mining and exploration of fossil fuels, the environment in which they are mined usually gets polluted or degraded.

Research shows that this may lead to acid rain, drastic climate change, pollution of aquatic life, spread of diseases that can kill both humans and animals, and other unfavorable and uncontrollable conditions that damage the ecosystems.¹

There is also concern that fossil fuel reserves are quickly depleting and may not actually be limitless.
Another energy source that is being used to generate electricity is nuclear energy. Nuclear power is mostly used in developed countries.

Nuclear energy is advantageous because it generates electricity through a self-sustained reaction; however, disposal of nuclear waste is a major challenge.

Also, in the event of an accident at the power plant, radioactive components are released to the environment. Nuclear radiation is very hazardous to humans, plants, animals, and the environment at large.

References

Godfrey, K.; Patrick, G. D.; Vincent, O. N. International Journal of Energy Research,2014, 2014, 1-19
Helmut, H.; Oda, B.; Mycle, S.; Antony, F. Estudos Avancados 21, 2007, 59, 253- 257.
Liao, S. K.; Chang, Y. H.; Wu, C. T.; Lai, Y. R.; Chen, W. Y. Journal of CO₂ Utilization. 2017, 21, 513-520
Haehnlein, S.; Bayer, P.; Blum, P. Renewable and Sustainable Energy Reviews, 2010,14, 2611–2625.
Solangi, K. H.; Islam, M. R.; Saidur, R.; Rahim, N. A.; Fayaz, H. Renewable and Sustainable Energy Reviews, 2011, 15, 2149–2163.
George, W. C.; Nathan, S. American Institute of Physics, 2007, 4,