Proceedings of International Conference on Perovskite and Organic Photovoltaics and Optoelectronics (IPEROP19)
DOI: https://doi.org/10.29363/nanoge.iperop.2019.019
Publication date: 23rd October 2018
Perovskite solar cells (PSCs) have been attracting much attention from researchers and engineers due to their high performance and low cost. As the research on PSCs proceeds, the structure has gradually evolved from the Graetzel structure to a sandwich structure which is the most widely used structure for high-performance PSCs. Behind the scenes, improvement of the perovskite crystallinity has played an important role in promoting the structural evolution. In the beginning, ultra-small perovskite crystal could only be used as a sensitizer in Graetzel structure.[1] It was not until crystal size matched film thickness that the sandwich structure became the main structure for PSCs. Recently, crystal size in perovskite thin films already reached several tens of micrometers, much larger than the thickness of the film.[2] How can we take advantage of the enlarged crystal size and further boost the efficiency of PSCs?
Here, we propose that the integrated-back-contact (IBC) structure, which has been widely used in Si photovoltaics, maybe the next-generation structure for PSCs. The IBC structure can largely reduce light loss by eliminating reflection and absorption caused by substrates. The Large crystal size of the perovskite film can help to reduce charge recombination between the two electrodes of the IBC structure. By using a numerical simulation method, we demonstrated that the IBC-PSCs would outperform sandwich-PSCs by 11%.[3] In the presentation, I will discuss detailed requirements to maximize the performance of IBC-PSCs.
This work is supported by JSPS KAKENHI Grant Number 18K14120 and Yazaki Memorial Foundation for Science and Technology.