Chemical Engineering (ChE) doctoral student Brandon Dunham has received a highly competitive $1,000 Graduate School Predissertation Research Grant from UMass Amherst to support one phase of his dissertation in progress, tentatively titled "Strategies to Improve the Performance and Stability of Planar, p-i-n Hybrid Organic-Inorganic Perovskite Solar Cells." Dunham’s dissertation research will investigate if he can inexpensively improve the efficiency and stability of perovskite solar cells, a next-generation solar material. If successful, says Dunham, his research “could change the way the world sees solar power forever.”
ChE Professor Shelly Peyton is Dunham’s graduate program director, and his dissertation supervisor/advisor is ChE Professor Christos Dimitrakopoulos.
Each year the Graduate School provides $80,000 to fund competitive Graduate School Dissertation Research Grants. This program recognizes the research and accomplishments of our outstanding graduate students and provides funds to assist recipients in completion of their dissertation. Grants are available for up to $1,000 for expenses incurred in connection with a student’s doctoral dissertation.
As Dunham explains in his predissertation grant application, with the continually increasing demand for energy as fossil fuels prove to be environmentally harmful and their sources progressively more limited, research and development activity has shifted focus to finding new and improved ways of harnessing energy from renewable sources. Generation of electricity from solar power is becoming gradually more popular due to increased efficiencies of photovoltaic devices, coupled with decreased manufacturing costs for solar panels.
“Hybrid organic-inorganic perovskites, a next-generation solar material, are of particular interest to researchers at the moment due to their excellent charge-transport properties, very strong light absorption, and low-cost solution-processability,” says Dunham. “Compared to crystalline silicon, the current commercial solar material, perovskite solar cells have exhibited similar laboratory sunlight-to-electricity, power-conversion efficiencies, and lower processing costs.”
Perovskites can also be fabricated on both flexible and rigid substrates, whereas silicon can only be fabricated on rigid substrates, since they require high-temperature processing.
However, according to Dunham, despite their advantages, perovskite solar cells continue to suffer from inherent instabilities in the presence of moisture, UV-Iight, and high-temperatures, causing them to degrade quickly to a photoinactive state. As such, improvements to stability in addition to efficiency are necessary for perovskite solar cells before they can be considered commercially viable and ultimately replace silicon on the market.
“If our efforts prove successful, and highly efficient perovskite solar cells can be mass-produced on flexible substrates using inexpensive processing, it could change the way the world sees solar power forever,” says Dunham. “Large-area panels would now be able to be wrapped around buildings, homes, or structures of various shapes, thus eliminating the need for flat panel installations of the inflexible silicon cells.”
Broadly speaking, this grant would support Dunham’s efforts to test proposed research methods for one portion of his dissertation: improving perovskite solar cell stability.
“The hope is that the critical information gathered during this phase will help to answer questions that will allow me to better understand how to proceed with the later data-collection component of this portion of my dissertation,” explains Dunham. “Specifically, this project will look to determine if single-layer or multi-layer graphene can act as a protective overlayer in a perovskite solar cell to effectively prevent moisture from diffusing into the device and causing unwanted degradation.”
Dunham expects to complete the phase of his research supported by the predissertation grant by December of 2018. (June 2018)