Another breakthrough for NREL: 24% efficiency for calcium titanite solar cells
Sep 19, 2022
NREL and a team of researchers from universities in the US have reported that the latest calcium titanite solar cell has achieved an efficiency of 24%, maintaining 87% of its original efficiency after 2,400 hours of operation at 55 degrees Celsius at double the sun's irradiance.
According to the report, this is "the highest efficiency of any cell structure of its type".
The National Renewable Energy Laboratory (NREL) and researchers from the University of Toledo, the University of Colorado at Boulder and the University of California, San Diego, placed layers on the glass substrate using a new molecule called 3-(aminomethyl)pyridine (3-APy), an architecture that differs from ordinary architectures in how the layers are deposited on the glass substrate.
The team chose the former method because of its high stability and integration into tandem solar cells. Using this architecture, the research added a new molecule called 3-(aminomethyl)pyridine (3-APy) to the surface of the chalcogenide solar cell. This molecule reacts with the amidine inside the cell to create an electric field on the surface of the chalcogenide layer.
According to Kai Zhu, a senior scientist at NREL's Centre for Chemistry and Nanoscience, "This suddenly gives a huge boost to battery performance, not only in terms of efficiency, but also stability."
Reactive surface engineering, which the researchers will refer to as 3-APy, can significantly improve inverted cell performance, and the researchers believe it can increase the efficiency of inverted cells from less than 23% to more than 25%.
Their research has been published in the scientific journal Nature under the title 'Surface reactions for efficient and stable inverted calcium titanite solar cells'.
In October 2020, NREL created a new chalcogenide material called Apex Flex, which reported a power conversion efficiency of 23.1% for 2-sided all-chalcogenide tandem solar cells on glass and 21.3% on flexible plastic substrates for vehicle applications (see 23.1% efficiency all-chalcogenide tandem solar cells).
Previously, German researchers from the University of Wuppertal announced an efficiency of 24% for a tandem calcium titanite and organic solar cell using an ultra-thin indium oxide layer (see 24% efficiency for tandem calcium titanite/organic cells).
In addition, the media reported that the team of Academician Huang Wei and Professor Chen Yonghua from the Institute of Advanced Materials at Nanjing University of Technology has been conducting research on the new solar material "chalcogenide" for seven years, with thousands of experiments, and has achieved a photovoltaic conversion efficiency of 24% for "chalcogenide solar cells". The team has achieved an international leading level of 24%.
