PM6:Y6 based solar cells have recently experienced a rapid increase of performance, achieving some of the highest power conversion efficiencies (PCEs) of organic solar cells reported so far. Moreover, under optimized fabrication conditions, PM6:Y6 blends have shown outstanding photo- and storage stability.<br/>Still, direct comparisons of different device structures and their effects on the solar cell degradation under continuous illumination in operating conditions have been hardly reported.<br/>In this work, we studied the influence of the device architecture on PM6:Y6 solar cells by examining the conventional and inverted structure, in combination with the processing of the photoactive blend with and without the additive chloronaphthalene. For each configuration, the electronic properties, maximum power point (MPP) tracking, as well as the absorber layer morphology were investigated.<br/>We found that the presence of the additive did not significantly affect the performance of the solar cells with conventional structure, leading to PCEs of approximately 14.5% in both cases. After 16 hours under continuous illumination and MPP tracking, 95% and 92% of the initial PCEs were retained in the devices with and without additive, respectively. On the contrary, inverted solar cells typically reached PCEs of 12% with and 13% without additive. However, regarding the decrease of the PCE during the MPP tracking, similar aging curves were observed, and the efficiencies dropped below 90% of their initial values. Further analyses revealed that the different degradation trends could be linked to a change in the crystallinity of Y6 and to its interaction with the interlayers.<br/>This study contributes to a better understanding of the aging mechanisms of PM6:Y6 solar cells, which will lead to improved electronic characteristics and longer device lifetimes.

Influence of device architecture on efficiency and stability of PM6:Y6 organic solar cells

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.