Ultrafast Charge Transfer in Operating Bulk Heterojunction Solar Cells. (13th February 2015)

• Record Type: Journal Article
• Authors: Zhong, Chengmei; Choi, Hyosung; Kim, Jin Young; Woo, Han Young; Nguyen, Thanh Luan; Huang, Fei; Cao, Yong; Heeger, Alan J.
• Is Part Of: Advanced materials. Volume 27:Number 12(2015)
• Page Start: 2036
• Page End: 2041
• Publication Date: 2015-02-13
• Subjects: bulk heterojunctions -- organic solar cells -- transient reflection spectroscopy -- ultrafast charge transfer; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201405284
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract : The ultrafast charge generation process in organic solar cell devices is investigated by transient reflection spectroscopy on five state‐of‐the‐art bulk heterojunction systems. The charge generation process in operating devices is found to be a combination of an ultrafast generation mechanism over several hundred femto­seconds and a slow process from pico­seconds to nanoseconds, limited by exciton diffusion dynamics. In addition, the lack of electric field dependence in the charge dynamics rules out geminate recombination as an important loss mechanism.