Signi cant Enhancement in Built-in Potential and Charge Carrier Collection of Organic Solar Cells using 4-(5-hexylthiophene-2-yl)-2,6-bis(5-tri uoromethyl)thiophen-2-yl)pyridine as a Cathode Bu er Layer
- Received Date: 2014-05-08
- Organic solar cells, Cathode buffer layer, Built-in potential, Charge carrier collection, Optical spacer effect
Abstract: An electron transporting material of TFTTP (4-(5-hexylthiophene-2-yl)-2,6-bis(5-trifluoromethyl)thiophen-2-yl)pyridine) was investigated as a cathode buffer layer to enhance the power efficiency of organic solar cells (OSCs) based on subphthalocyanine and C60. The overall power conversion efficiency was increased by a factor of 1.31 by inserting the TFTTP interfacial layer between the active layer and metallic cathode. The inner mechanism responsible for the performance enhancement of OSCs was systematically studied with the simulation of dark diode behavior and optical field distribution inside the devices as well as the characterization of device photocurrent. The results showed that the TFTTP layer could significantly increase the built-in potential in the devices, leading to the enhanced dissociation of charge transfer excitons. In addition, by using TFTTP as the buffer layer, a better Ohmic contact at C60/metal interface was formed, facilitating more efficient free charge carrier collection.
|Citation:||Yue Zang, Kang-li Cao, Jiang Huang, Qing Zhang, Jun-sheng Yu. Signi cant Enhancement in Built-in Potential and Charge Carrier Collection of Organic Solar Cells using 4-(5-hexylthiophene-2-yl)-2,6-bis(5-tri uoromethyl)thiophen-2-yl)pyridine as a Cathode Bu er Layer[J]. Chinese Journal of Chemical Physics , 2014, 27(5): 593-599. doi: 10.1063/1674-0068/27/05/593-599|