# Single‐Junction Organic Photovoltaic Cells with Approaching 18% Efficiency

“Single‐Junction Organic Photovoltaic Cells with Approaching 18% Efficiency” (2020), by Yong Yan Cui et al. Engineering research paper. Original abstract below, unchanged. No free PDF was found.

- Authors: Yong Yan Cui, Huifeng Yao, Jianqi Zhang, Kaihu Xian, Tao Zhang, Ling Hong, Yuming Wang, Ye Xu, Kangqiao Ma, Cunbin An et al.
- Published: March 29, 2020
- Field: Engineering
- DOI: https://doi.org/10.1002/adma.201908205
- Source: https://doi.org/10.1002/adma.201908205

## Abstract

Optimizing the molecular structures of organic photovoltaic (OPV) materials is one of the most effective methods to boost power conversion efficiencies (PCEs). For an excellent molecular system with a certain conjugated skeleton, fine tuning the alky chains is of considerable significance to fully explore its photovoltaic potential. In this work, the optimization of alkyl chains is performed on a chlorinated nonfullerene acceptor (NFA) named BTP-4Cl-BO (a Y6 derivative) and very impressive photovoltaic parameters in OPV cells are obtained. To get more ordered intermolecular packing, the n-undecyl is shortened at the edge of BTP-eC11 to n-nonyl and n-heptyl. As a result, the NFAs of BTP-eC9 and BTP-eC7 are synthesized. The BTP-eC7 shows relatively poor solubility and thus limits its application in device fabrication. Fortunately, the BTP-eC9 possesses good solubility and, at the same time, enhanced electron transport property than BTP-eC11. Significantly, due to the simultaneously enhanced short-circuit current density and fill factor, the BTP-eC9-based single-junction OPV cells record a maximum PCE of 17.8% and get a certified value of 17.3%. These results demonstrate that minimizing the alkyl chains to get suitable solubility and enhanced intermolecular packing has a great potential in further improving its photovoltaic performance.

Canonical page: https://nerdi.pages.dev/paper/W3013363765
Read three real papers a day in Nerdi (iPhone): https://apps.apple.com/app/apple-store/id6813826387?pt=128757794&ct=web-paper&mt=8