{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T16:14:54Z","timestamp":1787242494212,"version":"build-2736575974"},"reference-count":49,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,21]],"date-time":"2022-11-21T00:00:00Z","timestamp":1668988800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund of the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship, and Innovation, under the call RESEARCH\u2014CREATE\u2014INNOVATE","award":["T1EDK-01039"],"award-info":[{"award-number":["T1EDK-01039"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Obtaining white light from organic LEDs is a considerable challenge and, to realize white light emission, many studies have been conducted, primarily addressing two- or three-color blend systems as a promising strategy. In this work, pristine films, grown by spin coating, consisting of commercial blue Poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO), green Poly(9,9-dioctylfluorene-alt-benzothiadiazole) (F8BT), and red spiro-copolymer (SPR) light-emitting materials, were studied as reference materials. Afterward, binary (SPR doped in host PFO) and ternary (SPR and F8BT doped in host PFO) thin films were successfully prepared with various ratios. The characterization of the as-grown and thermally-treated blend films was focused on their optical and photophysical properties. After, the fabrication of OLED devices on glass substrates was carried out for the evaluation of a blend\u2019s composition and annealing in terms of the devices\u2019 electrical characteristics and electro-emission properties in order to achieve white light emission. Their analysis provided insights into the energy transfer mechanisms between the constituent materials, which were correlated to host\u2013guest interactions as well as to the structural changes originated by thermal treatment, leading to the crystallization of PFO. Finally, the OLEDs based on ternary blends approach the white light emission with (x, y) of (0.272, 0.346). These fabricated devices also exhibit turn-on voltages as low as 3 V, accompanied by remarkable luminance values above 3000 cd\/m2.<\/jats:p>","DOI":"10.3390\/nano12224099","type":"journal-article","created":{"date-parts":[[2022,11,22]],"date-time":"2022-11-22T03:08:37Z","timestamp":1669086517000},"page":"4099","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Influence of Dopant Concentration and Annealing on Binary and Ternary Polymer Blends for Active Materials in OLEDs"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5264-4399","authenticated-orcid":false,"given":"Maria","family":"Gioti","sequence":"first","affiliation":[{"name":"Nanotechnology Lab LTFN, Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3167-6535","authenticated-orcid":false,"given":"Despoina","family":"Tselekidou","sequence":"additional","affiliation":[{"name":"Nanotechnology Lab LTFN, Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6563-7200","authenticated-orcid":false,"given":"Vasileios","family":"Foris","sequence":"additional","affiliation":[{"name":"Nanotechnology Lab LTFN, Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4676-3682","authenticated-orcid":false,"given":"Vasileios","family":"Kyriazopoulos","sequence":"additional","affiliation":[{"name":"Organic Electronic Technologies P.C. (OET), 20th KM Thessaloniki\u2014Tagarades, GR-57001 Thermi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8175-5768","authenticated-orcid":false,"given":"Kyparisis","family":"Papadopoulos","sequence":"additional","affiliation":[{"name":"Nanotechnology Lab LTFN, Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2536-5845","authenticated-orcid":false,"given":"Spyros","family":"Kassavetis","sequence":"additional","affiliation":[{"name":"Nanotechnology Lab LTFN, Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stergios","family":"Logothetidis","sequence":"additional","affiliation":[{"name":"Nanotechnology Lab LTFN, Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"},{"name":"Organic Electronic Technologies P.C. (OET), 20th KM Thessaloniki\u2014Tagarades, GR-57001 Thermi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1585","DOI":"10.1002\/adma.200400684","article-title":"White organic light-emitting devices for solid-state lighting","volume":"16","author":"Forrest","year":"2004","journal-title":"Adv. Mater."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1245","DOI":"10.1103\/RevModPhys.85.1245","article-title":"White organic light-emitting diodes: Status and perspective","volume":"85","author":"Reineke","year":"2013","journal-title":"Rev. Mod. Phys."},{"key":"ref_3","first-page":"1","article-title":"Organic light emitting diodes: Devices and applications","volume":"5","author":"Karzazi","year":"2014","journal-title":"Environ. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4081697","DOI":"10.1155\/2016\/4081697","article-title":"Specifics and challenges to flexible organic light-emitting devices","volume":"2016","author":"Aleksandrova","year":"2016","journal-title":"Adv. Mater. Sci. Eng."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"100547","DOI":"10.1016\/j.mser.2020.100547","article-title":"Towards high-power-efficiency solution-processed OLEDs: Material and device perspectives","volume":"140","author":"Wang","year":"2020","journal-title":"Mater. Sci. Eng. R"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"468","DOI":"10.1016\/j.ssc.2006.07.008","article-title":"High efficiency small molecule white organic light-emitting devices with a multilayer structure","volume":"139","author":"Yang","year":"2006","journal-title":"Solid State Commun."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2014","DOI":"10.1016\/j.orgel.2013.04.039","article-title":"Color stable multilayer all phosphor white organic light-emitting diodes with excellent color quality","volume":"14","author":"Zhang","year":"2013","journal-title":"Org. Electron."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2947","DOI":"10.1002\/pssa.201600651","article-title":"A comprehensive study of the optical properties of emitting polymers for efficient flexible OLED devices","volume":"213","author":"Gioti","year":"2016","journal-title":"Phys. Status Solidi A"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"827","DOI":"10.1016\/j.orgel.2012.12.039","article-title":"Energy transfer in polyfluorene copolymer used for white-light organic light emitting device","volume":"14","author":"Wang","year":"2013","journal-title":"Org. Electron."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1917","DOI":"10.1002\/adfm.200600988","article-title":"White Electroluminescence from a Single-Polymer System with Simultaneous Two-Color Emission: Polyfluorene Blue Host and Side-Chain-Located Orange Dopant","volume":"17","author":"Liu","year":"2007","journal-title":"Adv. Funct. Mater."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Tselekidou, D., Papadopoulos, K., Kyriazopoulos, V., Andreopoulou, A.K., Andrikopoulos, K., Kallitsis, J.K., Laskaraki, A., Logothetidis, S., and Gioti, M. (2021). Photophysical and electro-optical properties of copolymers bearing blue and red chromophores for single-layer white OLEDs. Nanomaterials, 11.","DOI":"10.3390\/nano11102629"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"117054","DOI":"10.1016\/j.jlumin.2020.117054","article-title":"Single-component white polymer light-emitting diode (WPLED) based on a binary tris-pyrazolonate-Sm-complex","volume":"221","author":"Liu","year":"2020","journal-title":"J. Lumin."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"109011","DOI":"10.1016\/j.dyepig.2020.109011","article-title":"Dual F\u00f6rster resonance energy transfer in ternary PFO\/MEH-PPV\/F7GA hybrid thin films for white organic light-emitting diodes","volume":"186","year":"2021","journal-title":"Dye. Pigment."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"5980","DOI":"10.1007\/s11664-019-07350-z","article-title":"Achieving White Emission from Solution Processable Blends of Polyvinylene Derivative Guests into a Polyfluorene Matrix","volume":"48","author":"Franchello","year":"2019","journal-title":"J. Electron. Mater."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Al-Asbahi, B.A., AlSalhi, M.S., Jumali, M.H.H., Fatehmulla, A., Qaid, S.M.H., Mujamammi, W.M., and Ghaithan, H.M. (2022). Conjugated Polymers-Based Ternary Hybrid toward Unique Photophysical Properties. Molecules, 27.","DOI":"10.3390\/molecules27207011"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"8158","DOI":"10.1002\/adfm.201603311","article-title":"Near-field energy transfer using Nanoemitters for optoelectronics","volume":"26","author":"Guzelturk","year":"2016","journal-title":"Adv. Funct. Mater."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1039\/DF9592700007","article-title":"10th Spiers Memorial Lecture. Transfer mechanisms of electronic excitation","volume":"27","year":"1959","journal-title":"Discuss Faraday Soc."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"7939","DOI":"10.1063\/1.370612","article-title":"Energy and charge transfer in organic light-emitting diodes: A soluble quinacridone study","volume":"85","author":"Shaheen","year":"1999","journal-title":"J. Appl. Phys."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2642","DOI":"10.1063\/1.371104","article-title":"Photoluminescence quantum yield of pure and molecularly doped organic solid films","volume":"86","author":"Mattoussi","year":"1999","journal-title":"J. Appl. Phys."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"908","DOI":"10.1038\/nature04645","article-title":"Management of singlet and triplet excitons for efficient white organic light-emitting devices","volume":"440","author":"Sun","year":"2006","journal-title":"Nature"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"723","DOI":"10.1016\/j.jlumin.2013.05.048","article-title":"Color optimization of single emissive white OLEDs via energy transfer between RGB fluorescent dopants","volume":"143","author":"Kim","year":"2013","journal-title":"J. Lumin."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1080\/10408430600932152","article-title":"High-Efficiency White Polymer Light-Emitting Diodes Based on Blended RGB Polymers","volume":"458","author":"Kwon","year":"2006","journal-title":"Mol. Cryst. Liq. Cryst."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"A32","DOI":"10.1016\/j.matpr.2021.02.686","article-title":"Optical and electrical characterization of blended active materials for white OLEDs (WOLEDs)","volume":"37","author":"Gioti","year":"2021","journal-title":"Mater. Today Proc."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"6612","DOI":"10.1016\/j.apsusc.2010.04.057","article-title":"Characterization of amorphous organic thin films, determination of precise model for spectroscopic ellipsometry measurements","volume":"256","author":"Farahzadi","year":"2010","journal-title":"Appl. Surf. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"371","DOI":"10.1063\/1.118064","article-title":"Parameterization of the optical functions of amorphous materials in the interband region","volume":"69","author":"Jellison","year":"1996","journal-title":"Appl. Phys. Lett."},{"key":"ref_26","unstructured":"Azzam, R., and Bashara, N. (1977). Ellipsometry and Polarized Light, North-Holland Pub."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"11749","DOI":"10.1103\/PhysRevB.45.11749","article-title":"Modeling the optical dielectric function of semiconductors: Extension of the critical-point parabolic-band approximation","volume":"45","author":"Kim","year":"1992","journal-title":"Phys. Rev. B"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1442","DOI":"10.1364\/OME.420697","article-title":"Optical, photophysical, and electrooptical studies on slot-die polyfluorene-based flexible OLED devices","volume":"11","author":"Gioti","year":"2020","journal-title":"Opt. Mater. Express"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1021\/ma048162t","article-title":"Crystalline Forms and Emission Behavior of Poly(9, 9-di-n-octyl-2, 7-fluorene)","volume":"38","author":"Chen","year":"2005","journal-title":"Macromolecules"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"6814","DOI":"10.1021\/acs.jpclett.8b02892","article-title":"How to correctly determine the band gap energy of modified semiconductor photocatalysts based on UV\u2013vis spectra","volume":"9","author":"Pacia","year":"2018","journal-title":"J. Phys. Chem. Lett."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"627","DOI":"10.1002\/pssb.19660150224","article-title":"Optical Properties and Electronic Structure of Amorphous Germanium","volume":"15","author":"Tauc","year":"1966","journal-title":"Phys. Status Solidi B"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"3523","DOI":"10.1039\/B206040J","article-title":"Excitation energy transfer and spatial exciton confinement in polyfluorene blends for application in light-emitting diodes","volume":"23","author":"Charas","year":"2002","journal-title":"J. Mater. Chem."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"S14","DOI":"10.1016\/j.cap.2017.11.012","article-title":"Experimental verification of F\u00f6rster energy transfer and quantum resonance between semiconductor quantum dots","volume":"18","author":"Kim","year":"2017","journal-title":"Curr. Appl. Phys."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.tsf.2013.11.122","article-title":"Energy transfer mechanism between terbium and europium ions zinc oxide and zinc silicates thin films","volume":"553","author":"Davesnne","year":"2014","journal-title":"Thin Solid Film."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1016\/j.tsf.2015.03.041","article-title":"Photoluminescence of atomic layer deposited ZrO2:Dy3+ thin films","volume":"583","author":"Kiisk","year":"2015","journal-title":"Thin Solid Film."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1537","DOI":"10.1021\/jp0301406","article-title":"Probing F\u00f6rster and Dexter energy-transfer mechanisms in fluorescent conjugated polymer Chemosensors","volume":"108","author":"Murphy","year":"2004","journal-title":"J. Phys. Chem. B"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1016\/S0040-6090(02)00638-7","article-title":"PL and EL properties of a novel Eu-containing copolymer","volume":"417","author":"Ling","year":"2002","journal-title":"Thin Solid Film."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"5752","DOI":"10.1021\/jp037724s","article-title":"Distance and orientation dependence of excitation transfer rates in conjugated systems:beyond the F\u00f6rster theory","volume":"108","author":"Wong","year":"2004","journal-title":"J. Phys. Chem. A"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1016\/j.tsf.2013.03.046","article-title":"Dispersion and aggregation of quantum dots in polymer-inorganic hybrid films","volume":"537","author":"Matvienko","year":"2013","journal-title":"Thin Solid Film."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1016\/j.jlumin.2011.08.039","article-title":"F\u00f6rster-type energy transfer mechanism in PF2\/6 to MEH-PPV conjugated polymers","volume":"132","author":"Alsalhi","year":"2012","journal-title":"J. Lumin."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"819","DOI":"10.1146\/annurev.bi.47.070178.004131","article-title":"Fluorescence energy transfer as a spectroscopic ruler","volume":"47","author":"Stryer","year":"1978","journal-title":"Annu. Rev. Biochem."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1016\/j.jlumin.2018.04.018","article-title":"F\u00f6rster electronic excitation energy transfer upon adsorption of meso-tetra(3-pyridyl)porphyrin on InP@ZnS colloidal quantum dots","volume":"200","author":"Tovstun","year":"2018","journal-title":"J. Lumin."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"3827","DOI":"10.1016\/j.polymer.2012.06.029","article-title":"Influence of thermal annealing temperature on electro-optical properties of polyoctylfluorene thin film: Enhancement of luminescence by self-doping effect of low-content a phase crystallites","volume":"53","author":"Chen","year":"2012","journal-title":"Polymer"},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Chew, K.W., Rahim, N.A.A., Teh, P.L., Hisam, N.S.A., and Alias, S.S. (2022). Thermal Degradation of Photoluminescence Poly(9, 9-dioctylfluorene) Solvent-Tuned Aggregate Films. Polymers, 14.","DOI":"10.3390\/polym14081615"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"2574","DOI":"10.1002\/adma.200602632","article-title":"Self-Dopant Formation in Poly(9, 9-di-n-octylfluorene) Via a Dipping Method for Efficient and Stable Pure-Blue Electroluminescence","volume":"19","author":"Lu","year":"2007","journal-title":"Adv. Mater. (Weinh. Ger.)"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"073303","DOI":"10.1063\/1.3323099","article-title":"Balanced charge transport and enhanced white electroluminescence from a single white emissive polymer via thermal annealing","volume":"96","author":"Niu","year":"2010","journal-title":"Appl. Phys. Lett."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"12890","DOI":"10.1021\/ja051891j","article-title":"Effects of packing structure on the optoelectronic and charge transport properties in poly(9, 9-di-n-octylfluorenealt-benzothiadiazole)","volume":"127","author":"Donley","year":"2005","journal-title":"J. Amer. Chem. Soc."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"235201","DOI":"10.1103\/PhysRevB.73.235201","article-title":"Temperature and field dependence of hole mobility in poly(9, 9-dioctylfluorene)","volume":"73","author":"Kreouzis","year":"2006","journal-title":"Phys. Rev. B"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.orgel.2005.02.002","article-title":"The interplay between the optical and electronic properties of light-emitting-diode applicable conjugated polymer blends and their phase-separated morphology","volume":"6","author":"Voigt","year":"2005","journal-title":"Org. Electron."}],"container-title":["Nanomaterials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-4991\/12\/22\/4099\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:23:01Z","timestamp":1760145781000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-4991\/12\/22\/4099"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,11,21]]},"references-count":49,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2022,11]]}},"alternative-id":["nano12224099"],"URL":"https:\/\/doi.org\/10.3390\/nano12224099","relation":{},"ISSN":["2079-4991"],"issn-type":[{"value":"2079-4991","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,11,21]]}}}