Perovskite Solar Cells See Advances in Efficiency, AI Tech
Two research breakthroughs in perovskite technology, one involving artificial intelligence, could pave the way for more efficient and affordable solar cells.
In renewable energy, perovskite solar cells have emerged as a potential improvement in the efficiency of conventional photovoltaic cells. The unique properties of perovskite in solar cells can lead to higher efficiency, lower-temperature processing, and lower material costs than conventional cells.
Perovskite solar cell. Image used courtesy of the U.S. Department of Energy
The solar industry has recently seen multiple notable breakthroughs from major research institutions. This article reviews two recent advancements in perovskite solar cells and the impact they may have on the industry.
What Is a Perovskite Solar Cell?
Perovskite solar cells contain the mineral perovskite, which has a crystal-like structure in its active layer. Unlike conventional silicon-based solar cells, perovskite cells are made from a hybrid organic-inorganic lead or tin halide-based material. This material offers several advantages over traditional silicon cells.
Perovskite solar cells offer some advantages over traditional cells. Image used courtesy of the US Department of Energy
One of the primary benefits of perovskite solar cells is their high power conversion efficiency, which means they can convert a larger portion of sunlight into electricity. Perovskites are known for their exceptional light absorption properties, allowing them to generate electricity even in low-light conditions. Additionally, they can be manufactured using simpler and cheaper methods than those required for silicon cells, such as solution processing techniques.
Another key advantage of perovskite cells is their tunability. The bandgap of the perovskite material can be adjusted by altering its composition, enabling the absorption of different light wavelengths more efficiently. This adaptability makes them suitable for tandem solar cells, where layers of materials are stacked to capture a broader spectrum of sunlight.
Northwestern University's Perovskite Efficiency Breakthrough
At Northwestern University, researchers have significantly improved perovskite solar cell efficiency. Perovskite materials, known for their ability to 'tune' the wavelengths of light they absorb, present a favorable alternative to traditional high-purity silicon wafers used in conventional solar cells.
Perovskite solar cell developed by Northwestern researchers. Image used courtesy of Northwestern University
The Northwestern team's innovation lies in addressing the electron loss challenges associated with perovskite solar cells. They introduced a dual-molecule solution targeting surface recombination—a process where electrons are lost due to defects on the surface—and recombination at the interface between layers. This approach led to a record-setting National Renewable Energy Lab-certified efficiency of 25.1%, a notable improvement over the previous best of 24.09%.
This development not only pushes the boundaries of perovskite cell efficiency but also marks a shift in research focus from the bulk absorber to the interfaces, crucial for enhancing both efficiency and stability of these cells.
Simultaneously, an Australian team comprising researchers from RMIT, Monash University, and the national science agency CSIRO has brought artificial intelligence (AI) into producing perovskite solar cells.
Researchers working with the automatic device characterization equipment. Image used of RMIT University
Traditionally, creating perovskite cells has been a laborious and error-prone process, often likened to alchemy rather than science. This team bypassed years of human labor by employing AI, substantially reducing human error and optimizing cell production. Their machine-learning model predicts many promising chemical recipes for new perovskite solar cells, enabling rapid innovation.
The result is a reproducible power-conversion efficiency of 16.9% without human intervention—a significant achievement considering the historical challenges in reproducing high-efficiency perovskite cells. This AI model represents a foundational step for further optimization, both in efficiency and stability, and has potential applications beyond perovskite to other solar cell types, including silicon-based and organic materials.
Future of Perovskite Cells
Both of these developments represent crucial milestones in the field of renewable energy. The increased efficiency achieved by the Northwestern University team and the innovative application of AI by the Australian researchers are reshaping the landscape of solar energy technology. As these technologies continue to evolve, they promise to enhance the viability of perovskite solar cells and play a pivotal role in the global transition toward more sustainable and cost-effective energy solutions.