TY - JOUR
T1 - Effects of the diphenyl ether additive in halogen-free processed non-fullerene acceptor organic solar cells
AU - Di Mario, Lorenzo
AU - Garcia Romero, David
AU - Pieters, Meike J.
AU - Eller, Fabian
AU - Zhu, Chenhui
AU - Bongiovanni, Giovanni
AU - Herzig, Eva M.
AU - Mura, Andrea
AU - Loi, Maria A.
N1 - Funding Information:
L. D. M., F. E., E. M. H. and M. A. L. acknowledge funding from SolarEraNet (No. NFA4R2ROPV). D. G. R. acknowledges the financial support from NWO organization. F. E. and E. M. H. acknowledge funding from the DFG (INST 91/443-1). F. E. thanks the Elite Study Program Macromolecular Science within the Elite Network of Bavaria (ENB) for support. Portions of this research were carried out at beamline 7.3.3 of the Advanced Light Source, which is supported by the Director of the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. A. M. acknowledge access to research infrastructure in CeSAR—Centro Servizi di Ateneo per la Ricerca – at Università degli Studi di Cagliari and thank Dr M. Marceddu for technical assistance. L. D. M., D. G. R. and M. A. L. thank A. F. Kamp and T. Zaharia for their technical support.
Publisher Copyright:
© 2022 The Royal Society of Chemistry.
PY - 2023/1/16
Y1 - 2023/1/16
N2 - The development of an environmentally friendly fabrication process for non-fullerene acceptor organic solar cells is an essential condition for their commercialization. However, devices fabricated by processing the active layer with green solvents still struggle to reach, in terms of efficiency, the same performance as those fabricated with halogenated solvents. The reason behind this is the non-optimal nanostructure of the active layer obtained with green solvents. Additives in solution have been used to fine-tune the nanostructure and improve the performance of organic solar cells. Therefore, the identification of non-halogenated additives and the study of their effects on the device performance and stability are of primary importance. In this work, we propose the use of diphenyl ether (DPE) as additive, in combination with the non-halogenated solvent o-xylene, to fabricate organic solar cells with a completely halogen-free process. Thanks to the addition of DPE, a best efficiency of 11.7% have been obtained for the system TPD-3F:IT-4F, an increase over 15% with respect to the efficiency of devices fabricated without additive. Remarkably, the stability under illumination of the solar cells is also improved when DPE is used. The addition of DPE has effects on the molecular organization in the active layer, with an enhancement in the donor polymer ordering, showing a higher domain purity. The resulting structure improves the charge carrier collection, leading to a superior short-circuit current and fill factor. Furthermore, a reduction of the non-radiative recombination losses and an improved exciton diffusion, are the results of the superior molecular ordering. With a comprehensive insight of the effects of DPE when used in combination with a non-halogenated solvent, our study provides an approach to make the fabrication of organic solar cell environmentally friendlier and more suitable for large scale production.
AB - The development of an environmentally friendly fabrication process for non-fullerene acceptor organic solar cells is an essential condition for their commercialization. However, devices fabricated by processing the active layer with green solvents still struggle to reach, in terms of efficiency, the same performance as those fabricated with halogenated solvents. The reason behind this is the non-optimal nanostructure of the active layer obtained with green solvents. Additives in solution have been used to fine-tune the nanostructure and improve the performance of organic solar cells. Therefore, the identification of non-halogenated additives and the study of their effects on the device performance and stability are of primary importance. In this work, we propose the use of diphenyl ether (DPE) as additive, in combination with the non-halogenated solvent o-xylene, to fabricate organic solar cells with a completely halogen-free process. Thanks to the addition of DPE, a best efficiency of 11.7% have been obtained for the system TPD-3F:IT-4F, an increase over 15% with respect to the efficiency of devices fabricated without additive. Remarkably, the stability under illumination of the solar cells is also improved when DPE is used. The addition of DPE has effects on the molecular organization in the active layer, with an enhancement in the donor polymer ordering, showing a higher domain purity. The resulting structure improves the charge carrier collection, leading to a superior short-circuit current and fill factor. Furthermore, a reduction of the non-radiative recombination losses and an improved exciton diffusion, are the results of the superior molecular ordering. With a comprehensive insight of the effects of DPE when used in combination with a non-halogenated solvent, our study provides an approach to make the fabrication of organic solar cell environmentally friendlier and more suitable for large scale production.
UR - http://www.scopus.com/inward/record.url?scp=85147153569&partnerID=8YFLogxK
U2 - 10.1039/d2ta08603d
DO - 10.1039/d2ta08603d
M3 - Article
AN - SCOPUS:85147153569
SN - 2050-7488
VL - 11
SP - 2419
EP - 2430
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
IS - 5
ER -