A team of scientists led by Professor Michael Grätzel at EPFL and Dr. Dong Suk Kim at the Korea Institute of Energy Research has developed an innovative way of using quantum dots to boost perovskite solar cell efficiency and scalability.
Perovskites are hybrid compounds made from metal halides and organic constituents. They have considerable potential in a variety of applications, such as LED lights, lasers, and photodetectors. Still, their most significant contribution is in solar cells, where they are poised to eclipse silicon counterparts.
One of the challenges in commercializing perovskite solar cells is that when they scale up, their power-conversion efficiency and operational stability decrease, making it difficult to maintain good performance in a whole solar cell.
Peroxide solar cells have made significant development in recent years, but there is still much space for improvement. A layer of quantum dots has now been added to the mix, resulting in a more stable solar cell with near-record efficiency.
Peroxide materials make good solar cells for a variety of reasons. Their films absorb the full visible light spectrum efficiently, are affordable to produce, lightweight, and flexible.
However, this type of battery has a number of flaws, one of which is a lack of stability. It may decline in real-world settings, resulting in a considerable reduction in conversion efficiency.
Scientists have attempted to add bulky molecules, old pigments, two-dimensional additives, or capsicum compounds to boost stability in the past.
In the latest study, researchers from EPFL and the Korea Energy Research Institute investigated a new component called quantum dots. When lighted, these small particles generate a certain color of light, and they’re starting to show up in items like televisions and solar cells.
In this example, the device’s electron transport layer was built of quantum dots made of a sort of tin oxide. This layer carries the peroxide-generated electrons to the electrodes, allowing the energy to be utilized.
Quantum dots, as opposed to the titanium dioxide substance commonly employed for the layer, improve the device’s ability to catch the light while reducing the impacts between the two layers.
Overall, the study discovered that peroxide solar cells with quantum dot layers were as efficient as 25.7 percent, narrowly missing the current peroxide record of 0.08 square centimeters (0.01 inches). 0.1% of the population.
The efficiency of the larger solar cells was equally good: the 1-square-centimeter (0.2-inch) cell had a 23.3 percent efficiency, the 20-square-centimeter (3.1-inch) cell had a 21.7 percent efficiency, and the 64-square-centimeter (9.9-inch) cell had a 20.6 percent efficiency.
