Self-Doped, n-Type Perylene Diimide Derivatives as Electron Transporting Layers for High-Efficiency Polymer Solar Cells

4 years ago

Self-Doped, n-Type Perylene Diimide Derivatives as Electron Transporting Layers for High-Efficiency Polymer Solar Cells

Zengqi Xie, Yuguang Ma, Wenqiang Zhang, Fei Huang, Yong Cao, He Yan, Zhenfeng Wang, Nannan Zheng

Perylene diimide (PDI) with high electron affinities are promising candidates for applications in polymer solar cells (PSCs). In addition, the strength of π-deficient backbones and end-groups in an n-type self-dopable system strongly affects the formed end-group-induced electronic interactions. Herein, a series of amine/ammonium functionalized PDIs with excellent alcohol solubility are synthesized and employed as electron transporting layers (ETLs) in PSCs. The electron transfer properties of the resulting PDIs are dramatically tuned by different end-groups and π-deficient backbones. Notably, electron transfer is observed directly in solution in self-doped PDIs for the first time. A significantly enhanced power conversion efficiency of 10.06% is achieved, when applying the PDIs as ETLs in PTB7-Th:PC71BM-based PSCs. These results demonstrate the potential of n-type organic semiconductors with stable n-type doping capability and facile solution processibility for future applications of energy transition devices. Serials self-doped perylene diimides (PDIs) are investigated and applied as electron transporting layer in high-efficiency polymer solar cells. Variations of both the π-deficient PDI cores and the electron-donating amine/ammonium end-groups induce electronic interactions between them in different intensity, which facilitates the management of the electron transfer properties for applications in organic electronics.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/aenm.201700232