Building a planar single and binary blend stack ternary organic solar cells

• Published in: Flexible and printed electronics Vol. 4; no. 3; pp. 34003 - 34010
• Main Authors: Yadav, Shubham, Iyer, S Sundar Kumar
• Format: Journal Article
• Language: English
• Published: IOP Publishing 12.08.2019
• Subjects: 3,4; 4,7(2,1,3-benzothiadiazole)] (PCPDTBT); binary blend solar cell; butyric acid methyl ester (PCBM); cyclopenta [2,1; dithiophene; organic solar cells; poly (3-hexylthiophene) (P3HT) [6,6]-Phenyl C; Poly[2,6-(4,4-bis-(2-ethylhexyl)-4; single layer solar cell; ternary solar cells
• ISSN: 2058-8585; 2058-8585
• DOI: 10.1088/2058-8585/ab35f8

Higher efficiency ternary organic solar cells (OSCs) can be built by capping the photoactive layer of a binary blend OSC device with a planar single photovoltaic layer, with an absorption spectrum complementary to that for the original blend layer. A ternary active layer material system of two donors poly (3-hexylthiophene) and Poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta [2,1-b;3,4-b′] dithiophene)-alt-4,7(2,1,3-benzothiadiazole)] and an acceptor [6,6]-Phenyl C61 butyric acid methyl ester is considered in this work. From the various possibilities of building ternary device with a binary blend layer and planar single layer stacks, the low efficiency options are eliminated. Simulation studies of the final structure are carried out to decide the optimum thicknesses of the different photovoltaic layers. The optimised ternary device fabricated shows an improvement in power conversion efficiency of up to 23.5% over the base binary blend solar cells. The primary contribution to efficiency improvement is from the increase in short circuit current from the increased harvest of photons by the planar single capping layer.