Lee, Jaehyeon Shim, Jaeho Lee, Joo Song Choi, Chel-Jong Yim, Sang-Youp Jin, Yeonghoon Yu, Kyoungsik Park, Young Jae Ahn, Seokhoon Son, Dong Ick 2024-01-19T13:32:50Z 2024-01-19T13:32:50Z 2022-01-10 2021-10-07 2050-7526 https://pubs.kist.re.kr/handle/201004/116267 Recently, research on the use of additives in photoactive layers to improve the efficiency of solar cells has continued to be conducted. Among them, carbon-based additives serve to increase a device's efficiency by simply and effectively improving the carrier movement. In this work, inverted polymer solar cells (iPSCs) are fabricated based on a blend of PTB7-Th:PC71BM and PTB7:PC71BM bulk heterojunction as photoactive materials using mixed additives of 4Cl-carbon-based contorted hexabenzocoronene (4Cl-cHBC). The 4Cl-cHBC additives, a kind of contorted polycyclic aromatic hydrocarbon, added to bulk heterojunction in the iPSC devices, provide a cocrystal modifier and effective charge separation to enhance device performance. The reason for this efficiency improvement is that cocrystal is formed due to a combination between 4Cl-cHBC and the PTB7-Th:PC71BM bulk heterojunction, which reduces bimolecular recombination in the device and significantly increases short-circuit current and fill factor. The R-S and R-Sh values of iPSCs based on PTB7-Th:PC71BM with and without the 4Cl-cHBC additives decreased from 7.0 omega cm(2) to 4.0 omega cm(2), and increased from 813 omega cm(2) to 1226 omega cm(2), respectively. The calculated average carrier lifetimes at 500 nm for PTB7-Th:PC71BM and PTB7-Th:PC71BM with 4Cl-cHBC additives are 4.46 ps and 3.06 ps, respectively. The carrier lifetimes show that the charge separation of PTB7-Th:PC71BM with 4Cl-cHBC additives is more than 45% faster. As a result, the iPSCs based on the blend of PTB7-Th:PC71BM and PTB7:PC71BM with 4Cl-cHBC additives showed maximum power conversion efficiencies of 9.46 and 8.62%, which were 20.6 and 19.95% higher than those of the reference, respectively. English ROYAL SOC CHEMISTRY NANOPARTICLES MORPHOLOGY EFFICIENCY NANOSHEETS AG Improving the performance of photovoltaic cells based on nanocomposites with contorted polycyclic aromatic hydrocarbon additive in bulk heterojunction Article 10.1039/d1tc02932k 1 JOURNAL OF MATERIALS CHEMISTRY C, v.9, no.38, pp.13081 - 13089 JOURNAL OF MATERIALS CHEMISTRY C 9 38 13081 13089 scie scopus 000700207000001 2-s2.0-85116915909 Materials Science, Multidisciplinary Physics, Applied Materials Science Physics Article NANOPARTICLES MORPHOLOGY EFFICIENCY NANOSHEETS AG photovoltaic cells hydrocarbon bulk heterojunction contorted hexabenzocoronene bimolecular recombination