The US National Renewable Energy Laboratory (NREL) and team of researchers from University of Toledo, the University of Colorado–Boulder, and the University of California–San Diego have reported a 'record' 24% certified stabilized efficiency for perovskite solar cell using inverted architecture.
An inverter architecture differs from a normal architecture in terms of how the layers are deposited on the glass substrate. The team chose the former method for its high stability and integration into tandem solar cells.
Using the inverter architecture, they added a new molecule called 3-(Aminomethyl) pyridine (3-APy) to the perovskite solar cell surface. The molecule reacted to the formamidinium within the cell to create an electric field on the surface of the perovskite layer.
"That suddenly gave us a huge boost of not only efficiency but also stability," said Senior Scientist in the Chemistry and Nanoscience Center at NREL, Kai Zhu.
They were able to achieve 24% efficiency under 1-sun illumination, making it the 'highest reported of its kind'. The highly efficient cell also retained 87% of its original efficiency after 2,400 hours of operation at 55 degrees Celsius, explained NREL.
Calling 3-APy reactive surface engineering as an effective approach to significantly enhance the performance of inverted cells, the researchers believe it can improve the efficiency of an inverted cell from less than 23% to greater than 25%.
Their research has been published in scientific journal Nature under the title Surface Reaction for Efficient and Stable Inverted Perovskite Solar Cells.
In October 2020, NREL created a new perovskite material called Apex Flex to report 23.1% power conversion efficiency for 2-terminal all-perovskite tandem solar cells on glass and 21.3% on flexible plastic substrates, suitable for vehicular applications (see 23.1% Efficiency For All-Perovskite Tandem Solar Cells).
Previously, German researchers from the University of Wuppertal announced 24% efficiency for perovskite and organic tandem solar cells using ultra-thin layer of indium oxide (see 24% Efficiency For Perovskite/Organic Tandem Cell).