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

Said Karim Shah; Jahangeer Khan; Irfan Ullah; Yaqoob Khan; Said Karim Shah; Jahangeer Khan; Irfan Ullah; Yaqoob Khan

doi:10.3934/matersci.2017.3.789

AIMS Materials Science

2017, Volume 4, Issue 3: 789-799. doi: 10.3934/matersci.2017.3.789

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Research article Topical Sections

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

Received: 07 March 2017 Accepted: 08 June 2017 Published: 16 June 2017

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.
- 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[J]. AIMS Materials Science, 2017, 4(3): 789-799. doi: 10.3934/matersci.2017.3.789

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Abstract

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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