Role of Platinum Octaethylporphyrin(PtOEP) in PCPDTBT: PCBM solar cell performance

Abstract

Abstract Bulk heterojunction polymer solar cells based on poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b’]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole) [6,6]:- Phenyl-C61 butyrie acid methyl ester (PCPDTBT: PCBM) blends were doped by different amount(0,0.5,1,2,3 and 6 mg) from Platinum Octaethylporphyrin(PtOEP). The effect of PtOEP on the surface morphology, Raman spectra, optical absorbance, and photovoltaic properties was studied. We found that the best performance for PCPDTBT: PCBM device with 33.5% enhancement in power conversion efficiency was achieved when we added 1 mg from PtOEP. The impedance spectroscopy was examined in the frequency range from 0.025 to 1000 KHz. The equivalent circuit model was analyzed in detail to evaluate the interface and recombination processes. The highest diffusion coefficient and mobility were found for PCPDTBT: PCBM: PtOEP(1 mg)device, which records a more efficient exciton dissociation at the interface and a faster charge transport processes.