We present the results of applying multi-layer graphene (MLG) films as transparent conductive electrodes in organic photovoltaic devices (OPVs). The MLG films synthesized at different growth temperatures by chemical vapor deposition were applied to OPVs. The performance of OPVs with 1000 °C-grown MLG films was found to be the best with a power conversion efficiency (PCE) of ∼1.3%. The PCE was further enhanced when a hole-blocking TiOX layer was inserted in the device structure, resulting in a PCE of ∼2.6% which is a significantly higher efficiency compared to other previously reported graphene-adopted photovoltaic cells. Our demonstration of the PCE-increase in the graphene-electrode OPVs may foster the application of the fast-progressing graphene technology toward more practical OPV technology.
Bibliographical noteFunding Information:
This work was supported by the National Research Laboratory Program, the National Core Research Center grant, the World Class University program, and the National Research Foundation of Korea (Grant No. 20090093869 ) from the Korean Ministry of Education, Science and Technology, and the Program for Integrated Molecular System at GIST. The authors thank Yun Chang Park at the National Nanofab Center for his comments and assistance in analyzing and obtaining the TEM images.
- Chemical vapor deposition
- Transparent electrode