Performance Improvement of Bulk Heterojunction Polymer Solar Cells with Metal Oxide Nanoparticles
In this study, we fabricated polymer solar cells with two different bulk heterojunction (BHJ), thieno(3,4-b)-thiophene/ benzodithiophene copolymer,(6,6)-phenyl C71 butyric acid methyl ester (PTB7/PC71BM), poly (3- hexylthiophene) and [6,6]-phenylC71butyric acid methyl ester (P3HT/PC71BM). For the two PSC devices the TiOx interlayer was inserted between the active layer (BHJ) and metal electrode. The performance enhancement of the devices with and without interlayer was investigated. X-ray diffraction (XRD) and UV-VIS measurements were used to investigate structural and optical properties of samples. The current–voltage (J-V) curves of the polymer solar cells with active area of ~ 10 mm2 were measured. We found that the TiOx layer improved the efficiency and stability of the devices compared with the same devices without TiOx interlayer. Also we observed that the PTB7/PC71BM/TiOx solar cell was much stable compared with P3HT/PC71BM/TiOx solar cell.
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