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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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Copyright Info: © 2017, Said Karim Shah, et al., licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution Licese (http://creativecommons.org/licenses/by/4.0)

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