Optical Materials最新文献

{"title":"Structural, mechanical and luminescence characteristics of gadolinium orthoniobate-tantalates doped with Tb, Er and Eu","authors":"M.N. Palatnikov,&nbsp;O.B. Shcherbina,&nbsp;M.V. Smirnov,&nbsp;S.M. Masloboeva","doi":"10.1016/j.optmat.2025.116950","DOIUrl":"10.1016/j.optmat.2025.116950","url":null,"abstract":"<div><div>Powders of gadolinium orthoniobate-tantalate doped by terbium, erbium and europium with the general formula Gd_0.979Tb_0.01Er_0.01Eu_0.001Nb_xТа_1-xO₄ (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9, 1) were synthesized by liquid-phase method. The influence of composition of Gd_0.979Tb_0.01Er_0.01Eu_0.001Nb_xТа_1-xO₄ ceramics on structural, mechanical and luminescence properties was studied. The structural parameters of the main phase of Gd_0.979Tb_0.01Er_0.01Eu_0.001Nb_xТа_1-xO₄ ceramics were calculated. The main phases of samples had the structure of monoclinic β-fergusonite. Increasing Ta content in obtained samples led to appearing a small amount (3–4 %) of orthorhombic phase Gd_0.333TaO₃. The morphological features of microstructure of ceramic samples were studied and their mechanical characteristics were evaluated. It was shown that Gd_0.979Tb_0.01Er_0.01Eu_0.001Nb_0.7Ta_0.3O₄ had the best mechanical characteristics. The study of photoluminescent properties of Gd_0.979Tb_0.01Er_0.01Eu_0.001Nb_xТа_1-xO₄ ceramics had shown that isomorphic substitution in the niobium-tantalum sublattice led to positional disorder of cations in the B-sublattice, which stimulated luminescence of rare-earth elements particularly Tb³⁺ cations. Thus, in Gd_0.979Tb_0.01Er_0.01Eu_0.001Nb_xТа_1-xO₄ ceramics there was a special concentration point (Nb:Ta = 1) at which the luminescence intensity was maximal. It was shown that as the Nb content decreased in the structure of Gd_0.979Tb_0.01Er_0.01Eu_0.001Nb_xТа_1-xO₄ ceramics the value of charge transfer energy between intrinsic luminescence centers and doped elements increased as well as splitting of multiplets into Stark levels increased due to the change of both distance between Me-Re (Me – Ta, Nb; Re – Tb, Er, Eu) and polarisation of ReO₈ polyhedron.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"163 ","pages":"Article 116950"},"PeriodicalIF":3.8,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143714410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Q-switched operation of erbium-doped fiber laser based on Ge2Sb2Te5 saturable absorber under positive and negative net dispersion conditions","authors":"Xiaoyu Zhao ,&nbsp;Xinxin Shang ,&nbsp;Shuaimeng Li ,&nbsp;Lezheng Wang ,&nbsp;Yutian He ,&nbsp;Hao Tan ,&nbsp;Yu Wei ,&nbsp;Shenggui Fu ,&nbsp;Guomei Wang ,&nbsp;Wenfei Zhang ,&nbsp;Caixun Bai ,&nbsp;Nannan Xu ,&nbsp;Cheng Lu ,&nbsp;Huanian Zhang","doi":"10.1016/j.optmat.2025.116946","DOIUrl":"10.1016/j.optmat.2025.116946","url":null,"abstract":"<div><div>In our experiment, Ge₂Sb₂Te₅ (GST)-Polyvinyl Alcohol (PVA) was prepared using the liquid phase exfoliation method. Many systematic characterizations of GST nanosheets were conducted. We used GST-PVA as a nonlinear saturable absorber and achieved both positive and negative dispersion Q-switched pulse operation by adjusting the length of the doped fiber. Under negative dispersion conditions, we obtained Q-switched pulses with a repetition frequency of up to 75.32 kHz and a central wavelength of 1560.3 nm. Subsequently, by increasing the length of the doped fiber, we obtained dual-wavelength Q-switched pulses with central wavelengths of 1531.88 nm and 1559.16 nm under positive dispersion conditions. The repetition frequency of the Q-switched fiber laser changed from 25.02 kHz to 49.92 kHz, with a tuning range of approximately 24.9 kHz. The maximum pulse energy reached 41.67 nJ. Furthermore, by adjusting the pump power, another type of dual-wavelength Q-switched pulse was recorded. We also observed the transition from dual-wavelength Q-switched pulses to dual-wavelength conventional soliton mode locked's transition state. This is the first time that GST-PVA has been used as a saturable absorber for Q-switched pulses and the first study of doped fiber lasers with GST-PVA as a saturable absorber under positive dispersion conditions. Our study indicates that GST has broad research prospects in the field of fiber lasers. GST nanosheets open up new opportunities for the development of future high-performance photonic devices.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"163 ","pages":"Article 116946"},"PeriodicalIF":3.8,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tailoring of optoelectronic and trapping effects in ZnO and ZnO:Mg 1D structures for DSSC photoelectrodes","authors":"A.I. Espinoza-Duarte ,&nbsp;A.L. Leal-Cruz ,&nbsp;A. Vera-Marquina ,&nbsp;R. Gómez-Fuentes ,&nbsp;A. Garzón-Roman ,&nbsp;C. Zúñiga-Islas","doi":"10.1016/j.optmat.2025.116943","DOIUrl":"10.1016/j.optmat.2025.116943","url":null,"abstract":"<div><div>This work is focused on tailoring optoelectronic behavior and trapping effects in ZnO and ZnO:Mg 1D nanostructures intended for DSSC photoelectrodes. ZnO and ZnO:Mg deposits on FTO-glass substrates were obtained by the CBD method at a relatively low temperature (90 °C) and short processing time (2 h). In addition, magnesium was incorporated as a dopant and varied (1 and 2 at. %) to obtain ZnO:Mg deposits with different optoelectronic and morphological characteristics. SEM results revealed the morphological evolution of ZnO deposits, transitioning from nanotubes to nanorods as the Mg increases from 0 to 2 at. %. Raman and XPS spectroscopies confirmed the formation of ZnO Wurtzite structures, as well as the incorporation of Mg ions in the ZnO host lattice. On the other hand, UV–Vis DRS revealed a significant influence of Mg ion concentration on the reflectance and optical bandgap of ZnO deposits. PL results indicated that both ZnO and ZnO:Mg deposits are rich in defects and traps induced by Mg incorporation, enabling the tailoring of optoelectronic properties. Additionally, when Mg at. % increases, UV, blue, and infrared emissions are quenched, while yellow emissions are enhanced. Lastly, a comprehensive analysis of the characteristics and behavior of resulting materials indicates that ZnO:Mg with 1 at. % of Mg exhibits the best attributes for photoelectrode, such as increased surface area, enhanced crystalline quality, and reduced recombination rates and defects. Noteworthy is that resulting materials exhibit those crucial characteristics required for DSSC photoelectrodes applications, and they could be considered for flexible electronic applications.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"162 ","pages":"Article 116943"},"PeriodicalIF":3.8,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reduced graphene oxide-carbon nanotubes nanocomposites-decorated porous silver nanodendrites for highly efficient SERS sensing","authors":"Nguyen Thi Huyen ,&nbsp;Luong Truc Quynh Ngan ,&nbsp;Le Thi Quynh Xuan ,&nbsp;Tran Ai Suong Suong ,&nbsp;Cao Thi Thanh ,&nbsp;Nguyen Van Tu ,&nbsp;Pham Thanh Binh ,&nbsp;Tran Van Tan ,&nbsp;Nguyen Viet Tuyen ,&nbsp;Dao Tran Cao ,&nbsp;Pham Van Hai ,&nbsp;Vu Xuan Hoa ,&nbsp;Nguyen Van Chuc","doi":"10.1016/j.optmat.2025.116935","DOIUrl":"10.1016/j.optmat.2025.116935","url":null,"abstract":"<div><div>In this study, an innovative nanocomposite of reduced graphene oxide-carbon nanotubes/porous silver dendrites (rGO-CNTs/pAgDs) was formed on silicon substrate using a straightforward plasma jet technique. This nanocomposite was employed as a surface-enhanced Raman scattering (SERS) substrate to detect hazardous pollutants, including rhodamine 6G (R6G) and pesticide residues like malathion (MAL). For R6G probe, the SERS substrate exhibited a good enhancement factor (EF) of 1.68 × 10⁷ and a low detection limit (LOD) of 2.43 × 10⁻¹³ M. Moreover, this SERS substrate owned a good stability for the SERS intensity which was reduced only by 12.4 % after aging time for 21 days and the relative standard deviation (RSD) values were lower than 15 %, revealing an excellent uniformity and reproducibility. For MAL detection, this SERS substrate exhibited a low LOD of 1.72 × 10⁻¹⁰ M. This SERS substrate shows great potential for detecting and monitoring hazardous pollutants and pesticide residues.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"162 ","pages":"Article 116935"},"PeriodicalIF":3.8,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advanced probing of Eu2+/Eu3+ photoemitter sites in BaAl2O4:Eu scintillators by synchrotron radiation X-ray excited optical luminescence probe","authors":"Latif U. Khan ,&nbsp;Ruba I. AlZubi ,&nbsp;Hassan K. Juwhari ,&nbsp;Yazan A. Mousa ,&nbsp;Zahid U. Khan ,&nbsp;Santiago J.A. Figueroa ,&nbsp;Philipp Hans","doi":"10.1016/j.optmat.2025.116937","DOIUrl":"10.1016/j.optmat.2025.116937","url":null,"abstract":"<div><div>The synchrotron radiation hard X-ray photons exhibit several advantages, such as monochromaticity, energy tunability and a desired penetration depth. This allows to precisely probe the chemical environment of the Eu²⁺/Eu³⁺ dopants' sites in a host lattice by X-ray absorption fine structure (XAFS) and X-ray excited optical luminescence (XEOL). Thus, tuning the photon energy of monochromatic X-rays around the L-edges of Europium and combining XAFS with the XEOL data provided an ideal probe for determining the oxidation state, local coordination environment and optical behavior of the Eu²⁺/Eu³⁺ sites. XEOL spectra of the X-ray induced luminescent samples S1 (BaAl₂O₄:Eu-BaCO₃) and S2 (BaAl₂O₄:Eu-BaCO₃/Al(OH)₃), measured under excitation of tunable Eu L_3,2,1-edges X-ray energies (7150, 7710, and 8150 eV) manifested that Eu²⁺ occupies more than one Ba sites in BaAl₂O₄ lattice, with a probable contribution from the BaCO₃. The Eu and Ba local site-specific L₃-edges X-ray absorption near edge structure (XANES) spectra, Continuous Cauchy wavelet transform (CCWT) and quantitative analyses of the extended X-ray absorption fine structure (EXAFS) data, demonstrated a mixed occupancy of Eu/Ba at the cation sites in BaAl₂O₄ lattice, dominantly for the S1 phosphor. However minor contribution from Eu site in the BaCO₃ cannot be neglected, as evidenced form the quantitative EXAFS fit of S1 phosphor. Quantitative phase analysis accomplished by Rietveld refinements of the experimental XRD patterns indicated the considerable enhancement in yield of BaAl₂O₄:Eu (S1) sample, irradiated with IR light, when compared to the S2. The emitting center's site specific XEOL spectroscopy in combination with XAFS validated the existence of europium predominantly in +3 oxidation state with minute Eu²⁺ impurity occupying multiple sites in the host lattice for the S1 and S2 phosphors.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"162 ","pages":"Article 116937"},"PeriodicalIF":3.8,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of morphology, structure and magnetic behavior of CdxZn1-xFe2O4@SiO2 nanocomposites with Cd2+ content and heat treatment","authors":"Thomas Dippong ,&nbsp;Iosif Grigore Deac ,&nbsp;Ioan Petean ,&nbsp;Erika Andrea Levei ,&nbsp;Oana Cadar","doi":"10.1016/j.optmat.2025.116936","DOIUrl":"10.1016/j.optmat.2025.116936","url":null,"abstract":"<div><div>The influence of Cd²⁺ content and heat treatment on the morphology, structure and magnetic behavior of Cd_xZn_1-xFe₂O₄ (x = 0.0; 0.2; 0.4; 0.6; 0.8; 1.0) nanoparticles encapsulated in SiO₂ produced by the sol-gel route was studied. At 800 °C, Fe₂SiO₄, Fe₂O₃ and CdO accompanied the poorly crystallized ferrites, while at 1200 °C the well crystallized ferrite was convoyed by Zn₂SiO₄ and SiO₂. Encapsulation of nano-sized Cd_xZn_1-xFe₂O₄ in inert SiO₂ allowed the particle size control, minimized agglomeration, and improved the magnetic behavior. The low heat treatment temperature produced well-individualized nanoparticles of ∼40 nm, with the particle diameter being larger than the ferrite crystallites due to the SiO₂ coating. Increasing the Cd²⁺ content resulted in small particle size, whereas increasing the heat treatment temperature led to larger particle size, resulting in submicron clusters. The increase of Cd²⁺ content and heat treatment temperature also determined the increase in lattice constant, density and hopping length and the decrease in crystallite size and porosity. The nanoparticles were found to be mesoporous with a narrow pore size distribution. The magnetic features increased with heat treatment temperature and decreased with increasing Cd²⁺ content until paramagnetic-like behavior was reached for CdFe₂O₄.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"162 ","pages":"Article 116936"},"PeriodicalIF":3.8,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel staggered quantum well design and in-surfactant GaN buffer layer in UVA light emitting diode heterostructures","authors":"Nor Syafiqah Azmi ,&nbsp;Muhammad Shahrul Nizam Suri ,&nbsp;Noratiqah Yusop ,&nbsp;Mohd Ann Amirul Zulffiqal Md Sahar ,&nbsp;Mohd Anas Ahmad ,&nbsp;Muhamad Ikram Md Taib ,&nbsp;Mohd Nazri Abd Rahman ,&nbsp;Muhammad Iznul Hisyam ,&nbsp;Tan Swee Tiam ,&nbsp;Ahmad Fakhrurrazi Ahmad Noorden ,&nbsp;Mohammad Amirul Hairol Aman ,&nbsp;Norzaini Zainal","doi":"10.1016/j.optmat.2025.116934","DOIUrl":"10.1016/j.optmat.2025.116934","url":null,"abstract":"<div><div>We propose a novel symmetric InGaN staggered quantum well (SQW) design for the growth of an InGaN/GaN UVA LED heterostructure, aiming at improving carriers’ confinement in the multi-quantum well (MQW) active region of the LED, especially at higher currents. In comparison to conventional methods, the SQW was inserted only in the last two QWs to shorten the overall growth time. Additionally, indium-surfactant was introduced during the growth of GaN buffer layer (In-surfactant GaN buffer layer) as an effort to improve the MQW growth further. With respect to the reference LED, i.e. without the SQW and the In-surfactant GaN buffer layer, the crystalline and surface properties improve for the LED with both SQW and In-surfactant GaN buffer layer. Moreover, the forward voltage can be as low as 3.23 V and the output power reaches approximately 25 mW at 100 mA with the SQW and In-surfactant GaN buffer layer.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"162 ","pages":"Article 116934"},"PeriodicalIF":3.8,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Al3+ ions on excitation energy transfer from fluorescent polyvinyl alcohol to Tb3+ ions","authors":"Ranjan Kumar ,&nbsp;Sumit Modanwal ,&nbsp;Richa Tripathi ,&nbsp;A.L. Fanai ,&nbsp;Hirdyesh Mishra","doi":"10.1016/j.optmat.2025.116933","DOIUrl":"10.1016/j.optmat.2025.116933","url":null,"abstract":"<div><div>The investigation of fluorescent polymers doped with various rare earth ions, particularly when sensitized by ultraviolet and visible radiation, is vital for improving the efficiency of photonic devices. In the present work, steady-state and time-domain photoluminescence measurements of fluorescent polyvinyl alcohol (PVA) films doped with Tb³⁺ and Al³⁺ ions were carried out to understand how the co-doping of Al³⁺ ions affects the optical properties of Tb³⁺ ions doped in the polymer matrix. A decrease in the intensity of the PVA fluorescence (450 nm) and phosphorescence (470 nm) emission bands, along with a corresponding reduction in decay times in the presence of Tb³⁺ ions, indicating energy transfer from PVA to Tb³⁺ with an efficiency of 41 %. With Al³⁺ ions, co-doping the PL intensity of the PVA fluorescence band increased, while the ⁵D₄ → ⁷F₆,_5,4 transition of the Tb³⁺ ion decreased, along with a reduction in decay time. These findings suggest that the presence of Al³⁺ ions reduces energy transfer by decreasing cross-relaxation processes and increasing the diversity of Tb³⁺ ion sites. This preliminary study highlights the potential for developing brighter, cost-effective optical materials with high photon flux control.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"162 ","pages":"Article 116933"},"PeriodicalIF":3.8,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Visible-light-driven CdS heterojunction photocatalysts of the MB degradation and water splitting","authors":"Marwah J. Kadhim ,&nbsp;M.A. Mahdi ,&nbsp;Atyaf M. Abdul Muttalib ,&nbsp;N.A. Abdullah ,&nbsp;Ali R. Naser ,&nbsp;Zahraa H. Harz","doi":"10.1016/j.optmat.2025.116925","DOIUrl":"10.1016/j.optmat.2025.116925","url":null,"abstract":"<div><div>Chemical bath deposition (CBD) is used to prepare Cadmium Sulfide (CdS) nanocrystalline thin films on glass and FTO/glass substrates. The CdS/Au nanocrystalline thin films were prepare by casting a solution of Au nanoparticles made using pulsed laser ablation technique. The successive ionic layer adsorption and reaction (SILAR) approach was used to create SnS thin films on CdS thin films, resulting in CdS/SnS heterojunction nanocrystalline thin films. The optical properties of prepared samples indicated that the optical band gap of the CdS and CdS/SnS nanocrystalline thin films created on a glass substrate is 2.34 and 1.51 eV, respectively. The optical band gaps of the CdS, CdS/Au, and CdS/SnS nanocrystalline thin films formed onto FTO/glass substrates are predicted to be 2.36, 2.29, and 2.19 eV, respectively. The photocatalytic activity of the synthesized CdS and CdS/Au nanocrystalline thin films was tested against the methylene blue (MB) dye under visible light irradiation. The photodegradation rate of the MB dye rose as the irradiation period increased. After 240 min of exposure, the photodegradation rate of MB dye was 76 % and 96 % for CdS and CdS/SnS nanocrystalline thin films, respectively. The linear sweep voltammetry (J-V) of CdS, CdS/Au, and CdS/SnS nanocrystalline thin films on FTO/glass substrates demonstrated a strong sensitivity to visible light. The Niqyst measurements of the CdS/SnS nanocrystalline thin film electrode have the smallest semicircle when compared to the CdS and CdS/Au thin films.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"162 ","pages":"Article 116925"},"PeriodicalIF":3.8,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acceptor-acceptor type perylenediimide-based polymeric acceptors with large 2-decyltetradecyl flexible side chain: Synthesis and impact of fluorination","authors":"Zheyu Li ,&nbsp;Daoyou Li ,&nbsp;Yifan Bao ,&nbsp;Pengzhi Guo ,&nbsp;Zezhou Liang ,&nbsp;Chunyan Yang ,&nbsp;Junfeng Tong","doi":"10.1016/j.optmat.2025.116932","DOIUrl":"10.1016/j.optmat.2025.116932","url":null,"abstract":"<div><div>Acceptor-acceptor (A-A) type perylenediimide (PDI)-based polymeric acceptors (PAs) possessed a high air stability and an excellent charge mobility. However, few efforts devoted to A-A type PDI-based polymeric acceptors and the interplay between the structure and photovoltaic performance was still nebulous. Herein, three A-A type PDI-based PAs PPDI-DT-DTBT, PPDI-DT-DTFBT and PPDI-DT-DTFFBT with large flexible 2-decyltetradecyl (DT) side chains were developed to probe into the effect of different fluorination at the benzothiadiazole (BT) moiety. And the donor-acceptor (D-A) type polymer acceptor PPDI-DT-2T without BT unit was prepared to make the comparison. All of them exhibited the high thermo-stability and solution state photo-stability. Gradually increased fluorine substituents acquired the blue-shifted absorption, the increased bandgap, the raised <em>E</em>_LUMO, more planar molecular configuration and strengthened aggregation. Accordingly, with the widely developed donor polymer PTB7-Th as electron donor, bulk heterojunction device based on monfluorinated PPDI-DT-DTFBT obtained the middle <em>V</em>_OC of 0.70 V, the highest <em>J</em>_SC of 6.22 mA cm⁻² and FF of 37.56 %, contributing to the winning power conversion efficiency (PCE) of 1.63 %. By contrast, fluorine-free PPDI-DT-DTBT- and difluorinated PPDI-DT-DTFFBT-based devices acquired the inferior PCEs of 1.31 % and 1.24 %. The control polymer accepter PPDI-DT-2T got the PCE of 1.27 % regardless of the high <em>V</em>_OC of 0.80 V as the result of high <em>E</em>_LUMO. The raised PCE after monofluorination was mainly originated from the increased <em>J</em>_SC and FF, which was due to the improved absorption and the higher electron mobility. The observed low efficiency in these DT-side chain modified PDI polymeric acceptors was probably due to the large aggregation and the coarse surface morphology resulting from limited solubility. Interestingly, fluorine-free PPDI-DT-DTBT film exhibited the <em>E</em>_LUMO of −3.85 eV and afforded the highest OFET electron mobility of 2.2 × 10⁻² cm² V⁻¹ s⁻¹. This finding implied that it was cautious to prolong the flexible side chain during the A-A type PDI-containing PAs, however, monofluorinating the benzothiadiazole moiety was an effective scenario by the virtue of tuning the molecular configuration and lifting the charge mobility, with an aim at elevating the photovoltaic performance in all-polymer solar cells.</div></div>","PeriodicalId":19564,"journal":{"name":"Optical Materials","volume":"162 ","pages":"Article 116932"},"PeriodicalIF":3.8,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}