Carbon nanotube based flexible counter electrode for quasi-solid state dye sensitized solar cells

Abstract

Low temperature fabrication of carbon nanotube based conductive composite polymer (CNT-CCP) film on conductive flexible substrate indium tin oxide coated polyethylene terephthalate film (ITO-PET) is developed as a low cost alternative to the Pt counter electrode especially for flexible quasi-solid state dye sensitized solar cells (DSSCs). The formation of three-dimensional carbon nanotube network provides the conductivity pathway which is improved with the carbon nanotube content and the film thickness increase. More importantly, the conductivity of CNT-CCP films greatly influences the performance of DSSCs. With high conductivity, good catalytic activity and especially the good consistence of the CNT-CCP with the polymer electrolyte, flexible CNT-CCP/ITO-PET counter electrode for the DSSC with the quasi-solid state composite polymer electrolyte exhibits performance of 4.24% (0.95Sun, AM1.5), which is 87% of the quasi-solid state DSSC with Pt counter electrode (4.87%). It indicates the CNT-CCP type counter electrode is promising for the flexible DSSCs.