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Optimization of active-layer thickness, top electrode and annealing temperature for polymeric solar cells

1 Department of Physics, Abdul Wali Khan University, Mardan 23200, Khyber Pukhtunkhwa, Pakistan
2 Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, China
3 National Centre for Physics, 44000, Islamabad, Pakistan

Topical Section: Materials Characterization

Organic solar cells, processed from solution at various optimizing device parameters, were investigated. The device’s active-layer film-thicknesses were optimized while depositing at different spin speeds where 120-nm-thick layer (D2) gives maximum power conversion efficiency of 2.9%, annealed at 165 °C. The reason is ascribed as sufficient light absorption, excitons dissociation/diffusion and carriers transportation. In the case of Ca/Al, being as a top electrode rather than LiF/Al and Al, substantial efficiency enhancement, from 1.70% to 2.78%, was obtained at low temperature, 130 °C, providing ease for charge collection and pertaining conductive nature of increased resistivity at high temperature.
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Keywords polymeric solar cells; solution processed; spin coating; active-layer thicknesses; top-metal electrodes; thermal annealing

Citation: Said Karim Shah, Jahangeer Khan, Irfan Ullah, Yaqoob Khan. Optimization of active-layer thickness, top electrode and annealing temperature for polymeric solar cells. AIMS Materials Science, 2017, 4(3): 789-799. doi: 10.3934/matersci.2017.3.789


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