Asmita Patra,
Suman Mahata,
Animesh Layek,
- Ph.D Scholar, Department of Physics, Jadavpur University, Kolkata-700032, West Bengal, India
- Ph.D Scholar, Department of Physics, Jadavpur University, Kolkata-700032, West Bengal, India
- Assistant Professor, Department of Physics, Jadavpur University, Kolkata-700032, West Bengal, India
Abstract
In many types of optoelectronic devices, layer of PEDOT: PSS is sandwiched between the indium-tin oxide (ITO) electrode and the active layer. Buffer PEDOT: PSS provides a well- defined work function which is higher than that of ITO (4.2eV), it smooths the ITO surface and so avoids shorts, and it also protects the active layer from ingress of indium or oxygen, leading to longer device lifetimes. The role of PEDOT: PSS is enormous. Unfortunately, PEDOT: PSS colloidal solution is strongly acidic and the PSS is strongly hygroscopic, which has the potential to cause degradation in adjacent layers, if water is not removed completely. Here to smooth the surface of ITO and to improve the durability of the device a buffer layer of Cu 2 O has newly been introduced, adopting SILAR method on ITO. A qualitative comparison has been performed with Cu 2 O buffer layer to the most familiar PEDOT: PSS buffer layer. The thorough characterization of both the buffer materials are performed by XRD and UV-Vis transmittance spectroscopy. The surface morphology has been analyzed by AFM. Finally, the influence of buffer layer on energy conversion efficiency has been tested for the MEH-PPV/PCBM based organic solar cell, by fabricating the device of configuration ITO/buffer-material/ MEH-PPV/PCBM/Aluminium. The improvement in open circuit voltage and light conversion efficiency implied the potential applicability of Cu 2 O over PEDOT: PSS as buffer electrode layer.
Keywords: Successive ionic layer adsorption and reaction (SILAR) method, buffer layer, organic solar cell, growth of Cu2O
[This article belongs to Journal of Thin Films, Coating Science Technology & Application ]
References
- Greczynski G, Kugler T, Keil M, Osikowicz W, Fahlman M, Salaneck WR. Photoelectron spectroscopy of thin films of PEDOT-PSS conjugated polymer blend: A mini-review and some new results. J Electron Spectrosc Relat Phenom. 2001;121(1-3):1-17. doi:10.1016/S0368-2048(01)00323-1.
- Pingree LSC, MacLeod BA, Ginger DS. The changing face of PEDOT films: Substrate, bias, and processing effects on vertical charge transport. J Phys Chem C. 2008;112(21):7922-7927. doi:10.1021/jp711838h.
- Fan B, Mei X, Ouyang J. Significant conductivity enhancement of conductive poly(3,4-ethylenedioxythiophene)(styrenesulfonate) films by adding anionic surfactants into polymer solution. Macromolecules. 2008;41:5971-5973. doi:10.1021/ma8012459.
- Huang J, Miller PF, Wilson JS, De Mello AJ, De Mello JC, Bradley DDD. Investigation of the effects of doping and post-deposition treatments on the conductivity, morphology, and work function of poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) films. Adv Funct Mater. 2005;15(2):290-296. doi:10.1002/adfm.200400073.
- Kim WH, Kushto GP, Kim H, Kafafi ZH. Effect of annealing on the electrical properties and morphology of a conducting polymer used as an anode in organic light-emitting devices. J Polym Sci B Polym Phys. 2003;41(21):2522-2528. doi:10.1002/polb.10646.
- Yang XH, Jaiser F, Stiller B, Neher D, Galbrecht F, Scherf U. Efficient polymer electrophosphorescent devices with interfacial layers. Adv Funct Mater. 2006;16(16):2156-2162. doi:10.1002/adfm.200500834.
- Kim YK, Shin MJ, Kim HJ. Annealing temperature effect of hole-collecting polymeric nanolayer in polymer solar cells. Macromol Res. 2008;16(3):185-188. doi:10.1007/BF03218850.
- Aasmundtveit KE, Samuelsen EJ, Pettersson LAA, Inganäs O, Johansson T, Feidenhans’l RJ. Structure of thin films of poly(3,4-ethylenedioxythiophene). Synth Met. 1999;101(1-3):561-564. doi:10.1016/S0379-6779(98)00315-4.
- Kim Y, Ballantyne AM, Nelson J, Bradley DDD. Effects of thickness and thermal annealing of the PEDOT layer on the performance of polymer solar cells. Org Electron. 2009;10(1):205-209. doi:10.1016/j.orgel.2008.10.003.
- Nguyen TP, Le Rendu P, Long PD, De Vos SA. Chemical and thermal treatment of PEDOT thin films for use in organic light emitting diodes. Surf Coat Technol. 2004;180:646-649.
- Aernouts T, Geens W, Poortmans J, Heremans P, Borghs S, Mertens R. Extraction of bulk and contact components of the series resistance in organic bulk donor-acceptor-heterojunctions. Thin Solid Films. 2002;403-404:297-301. doi:10.1016/S0040-6090(01)01584-X.
- Alemu D, Wei HY, Ho KC, Chu CW. Highly conductive PEDOT electrode by simple film treatment with methanol for ITO-free polymer solar cells. Energy Environ Sci. 2012;5(11):9662-9671. doi:10.1039/C2EE22595F.
- Nardes AM, Kemerink M, de Kok MM, Vinken E, Maturova K, Janssen RAJ. Conductivity, work function, and environmental stability of PEDOT thin films treated with sorbitol. Org Electron. 2008;9(5):727-734. doi:10.1016/j.orgel.2008.05.006.
- El-Korashy A, El-Zahed H, Radwan M. Optical studies of [N(CH3)4]2CoCl4, [N(CH3)4]2MnCl4 single crystals in the normal paraelectric phase. Physica B Condens Matter. 2003;334(1-2):75-81. doi:10.1016/S0921-4526(03)00019-X.
- Li W, Yang R, Wang D. CdTe solar cell performance under high-intensity light irradiance. Sol Energy Mater Sol Cells. 2014;123:249-254. doi:10.1016/j.solmat.2014.01.021.
Journal of Thin Films, Coating Science Technology & Application
| Volume | 13 | |
| Issue | 02 | |
| Received | 08/04/2026 | |
| Accepted | 18/05/2026 | |
| Published | 10/06/2026 | |
| Publication Time | 63 Days |