Discipline: Ecology Environmental and Earth Sciences
Subcategory: Chemical/Bimolecular/Process Engineering
Session: 4
Room: Exhibit Hall A
DeAnte' Fuller - Livingstone College
Co-Author(s): Anaiah Hooker Livingstone College, Gordon Miller Livingstone College, Josette Wilkes Livingstone College
For decades predictions were made that the amount of fossil fuel is limited and we would exhausts them in the near future. As it has happened, while we have found ways of extracting ever larger amounts of fossil fuels, it is the waste generated by their consumption that will limit our use of carbon based fuels. With climate change becoming an ever increasing concern we must shift our generation of energy to clean, carbon-free, renewable sources. It is the economic challenge that has stalled this shift. Solar power is among several options for renewable energy, and is one with potential to meet a large fraction of our need for energy. Currently, solar energy is expensive when compared to fossil fuels. Perovskite photovoltaic cells are easily assembled with relatively inexpensive materials and have the potential of becoming a real game changer in the pursuit of affordable solar energy. While there are several issues that need to be addressed with perovskite solar cells, this study addressed the issue of longevity. Eventually a perovskite cell with a lifetime of months was developed. FTO (Fluorine-doped Tin Oxide) glass is transparent conductive metal oxide that can be used in the fabrication of transparent electrodes for thin film photovoltaics. Onto this base a TiO2 (Titanium Dioxide) solution was deposited and annealed. TiO2 was used because it is cheap, non-toxic, easy to assemble, and is a semiconductor. It holds onto the perovskite solution when deposited on top. The perovskite solution was composed of Methylammonium lead halide (CH3NH3PbI3). This was the light based absorber material. The final layer is used as the hole transport material, Copper thiocyanate (CuSCN). CuSCN enhanced the performance of the solar cell by having a high stability, high hole mobility and suitable energy levels. This cell served as our control and we altered the deposition techniques for these layers and altered the material in selected layers as our experiments. The poly (3-hexylthiophene) Polymer (P3HT) was used as the hole transport material because of its solubility in various solvents. The crystallization of P3HT improves the efficiency of the solar cell and charge transport efficiency. The surface of the FTO glass was heated to a specific temperature. Then each layer was applied, and allowed to cool to room temperature after each annealing process. After the last solution cooled, a voltmeter was used to measure the voltage of the cell. Each layer helped the electrons pass through the solar cell and make a voltage. Depending on what hole transport material was used, you may get a different voltage. Therefore, the hole transport material was switched to P3HT because it extended the solar cell life span and increased output voltage from 50 mV to 200-300 mV. With the success of P3HT as a hole transport material future work will include altering the TiO2 layer, altering the composition of the perovskite layer, and testing new application techniques.
Funder Acknowledgement(s): NSF Support HBCU-UP
Faculty Advisor: Gordon Miller, gmiller@livingstone.edu
Role: The assembly of the perovskite solar cell, making the solutions, and measuring the voltage of the perovskite solar cell.