摘要
The role of bathophenanthroline (Bphen) as a buffer layer inserted between fullerene (C60) and Ag cathode in organic photovoltaic (OPV) cell was discussed. By introducing Bphen as a buffer layer with thicknes from 0 to 2.5 nm, the power conversion efficiency of the OPV cell based on copper phthalocyanine (CuPc) and C60 was increased from 0.87% to 2.25% under AM 1.5 solar illumination at an intensity of 100 mW/cm^2, which was higher than that of bathocuproine used as a buffer layer. The photocurrent-voltage characteristics showed that Bphen effectively improves electron transport through C60 layer into Ag electrode and leads to balance charge carrier transport capability. The influence of Bphen thickness on OPV cells was also investigated. Furthermore, the absorption spectrum shows that an additional Bphen layer enhances the light harvest capability of CuPc/C60.
基金
ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.60736005 and No.60425101-1), the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (No.60721001), the Provincial Program (No.9140A02060609DZ0208), the Program for New Century Excellent Talents in University (No.NCET- 06-0812), the Project Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (No.GGRYJJ08P 05), and the Young Excellence Project of Sichuan (No.09ZQ026-074).