Realization of solution processed multi-layer bulk heterojunction organic solar cells by electro-spray deposition

• DOI: 10.1016/j.orgel.2012.06.016
• Publication Date: 2012-06-27T20:20:05Z
• Authors: Mushtaq Ali; Mamatimin Abbas; Said Karim Shah; Rouzhaji Tuerhong; Amanda Generosi; Barbara Paci; Lionel Hirsch; Roberto Gunnella
• Keywords: Electro-spray; Organic solar cells; 0103 physical sciences; [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]; Solution processing; Multi-layer deposition; 01 natural sciences; 7. Clean energy

Electro-spray deposition (ESD) was applied to fabricate solution processed donor-acceptor bulk heterojunction organic photovoltaic devices with multi-layer structure. Solvent effect was observed when using different organic solvents. Power conversion efficiency (PCE) of the devices prepared from dichlorobenzene increased dramatically comparing to the ones from chloroform, owing to improved homogeneity of the films. ESD enabled us to fabricate solution processed multi-layer (donor/donor:acceptor/acceptor) devices with simple successive deposition steps. Energy Dispersive X-ray Reflectometry analysis confirmed distinct three layered structure of the active layers. Solar cell device parameters of the trilayer devices were compared to single layer devices and those of spin coated devices with the same donor:acceptor ratio and film thickness. Post-thermal treatment results showed that after annealing at 125 °C, trilayer devices exhibited best performance with the maximum PCE of 2.17%.