Pub Date : 2024-10-21DOI: 10.1016/j.synthmet.2024.117772
Hiroto Iwasaki , Yutaka Majima , Seiichiro Izawa
The low-voltage operation of blue organic light-emitting diodes (OLEDs) is critical for reducing power consumption and improving device lifetime. This review briefly summarizes the history and origin of low-voltage electroluminescence and its realization in recent reports. In particular, upconversion OLEDs, which use the charge transfer state as an intermediate state to facilitate blue emission via triplet–triplet annihilation, present a promising solution. Thus, continued efforts aimed at reducing the driving voltage, including the exploration of new materials and device structures, are expected to significantly contribute to expanding the applications of blue OLEDs.
{"title":"Low-voltage turn-on in blue organic light-emitting diodes","authors":"Hiroto Iwasaki , Yutaka Majima , Seiichiro Izawa","doi":"10.1016/j.synthmet.2024.117772","DOIUrl":"10.1016/j.synthmet.2024.117772","url":null,"abstract":"<div><div>The low-voltage operation of blue organic light-emitting diodes (OLEDs) is critical for reducing power consumption and improving device lifetime. This review briefly summarizes the history and origin of low-voltage electroluminescence and its realization in recent reports. In particular, upconversion OLEDs, which use the charge transfer state as an intermediate state to facilitate blue emission via triplet–triplet annihilation, present a promising solution. Thus, continued efforts aimed at reducing the driving voltage, including the exploration of new materials and device structures, are expected to significantly contribute to expanding the applications of blue OLEDs.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117772"},"PeriodicalIF":4.0,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142530128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-13DOI: 10.1016/j.synthmet.2024.117769
Yuqing Cao , Ling Zhu , Shuai Chen , Jie Fang , Lishan Liang , Youliang Shen
Metal based products are widely used, but they are susceptible to corrosion from environmental media, thereby affecting their performances and lifespan. Conducting polymers (CPs), as a series of important materials in organic electronics, have shown extensive corrosion prevention applications in fields such as ships and marine facilities, grounding system equipment, and military facilities, etc. Their development provides great safety, economic and social values, and has been one focus of academic and industrial circles. This is due to the unique reversible redox properties and tunability of CPs, which not only enable the rapid formation of passivation layer on the metal surface to prevent further corrosion from occurring. But at the same time, the coatings can be optimized according to different application requirements. This paper emphasizes the promising working mechanisms of CPs in anticorrosion field, introduces the commonly used methods for effectiveness evaluation, and also significantly discusses the aspects of their material system modulation and practical application. The existing challenges are also highlighted and future developments are prospected in detail. It is hoped to enlighten and drive scholars and technicians working in various cross-cutting areas covering anticorrosion, coatings, polymers, composites, and organic electronics, etc.
{"title":"Conducting polymers based composite materials towards anticorrosion applications","authors":"Yuqing Cao , Ling Zhu , Shuai Chen , Jie Fang , Lishan Liang , Youliang Shen","doi":"10.1016/j.synthmet.2024.117769","DOIUrl":"10.1016/j.synthmet.2024.117769","url":null,"abstract":"<div><div>Metal based products are widely used, but they are susceptible to corrosion from environmental media, thereby affecting their performances and lifespan. Conducting polymers (CPs), as a series of important materials in organic electronics, have shown extensive corrosion prevention applications in fields such as ships and marine facilities, grounding system equipment, and military facilities, etc. Their development provides great safety, economic and social values, and has been one focus of academic and industrial circles. This is due to the unique reversible redox properties and tunability of CPs, which not only enable the rapid formation of passivation layer on the metal surface to prevent further corrosion from occurring. But at the same time, the coatings can be optimized according to different application requirements. This paper emphasizes the promising working mechanisms of CPs in anticorrosion field, introduces the commonly used methods for effectiveness evaluation, and also significantly discusses the aspects of their material system modulation and practical application. The existing challenges are also highlighted and future developments are prospected in detail. It is hoped to enlighten and drive scholars and technicians working in various cross-cutting areas covering anticorrosion, coatings, polymers, composites, and organic electronics, etc.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117769"},"PeriodicalIF":4.0,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445313","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}
Pub Date : 2024-10-10DOI: 10.1016/j.synthmet.2024.117768
Xiaoming Zhou, Yang Liu
One of the important objectives for the development of enhanced lithium-ion batteries is developing high-performance silicon-based anodes with durable operational capability. Herein, a three-dimensional graphene-decorated core-shell Si/C composite is fabricated by the in-situ polymerization of organic pyrrole molecule and pyrolysis process, in which the melamine formaldehyde resin is subtly used as three-dimensional porous framework to offer abundant loading area for the uniform dispersion of active silicon nanoparticles. Meanwhile, the core-shell structure deriving from polypyrrole in the composite can effectively buffer the volume change of silicon ingredient and avoid the direct contact with the electrolyte during the cycling process, leading to the improved structural stability and electrochemical performance. The outermost layer of graphene nanosheets is designed to enhance the electrical conductivity of the electrode. As a result, the synthesized Si/C/graphene composite exhibits a high capacity and excellent cycling performance. This work reveals that combining a three-dimensional carbon substrate with a core-shell structure might be a promising solution for anode materials with obvious volume transformation.
{"title":"Preparation of core-shell Si/C/graphene composite for high-performance lithium-ion battery anodes","authors":"Xiaoming Zhou, Yang Liu","doi":"10.1016/j.synthmet.2024.117768","DOIUrl":"10.1016/j.synthmet.2024.117768","url":null,"abstract":"<div><div>One of the important objectives for the development of enhanced lithium-ion batteries is developing high-performance silicon-based anodes with durable operational capability. Herein, a three-dimensional graphene-decorated core-shell Si/C composite is fabricated by the in-situ polymerization of organic pyrrole molecule and pyrolysis process, in which the melamine formaldehyde resin is subtly used as three-dimensional porous framework to offer abundant loading area for the uniform dispersion of active silicon nanoparticles. Meanwhile, the core-shell structure deriving from polypyrrole in the composite can effectively buffer the volume change of silicon ingredient and avoid the direct contact with the electrolyte during the cycling process, leading to the improved structural stability and electrochemical performance. The outermost layer of graphene nanosheets is designed to enhance the electrical conductivity of the electrode. As a result, the synthesized Si/C/graphene composite exhibits a high capacity and excellent cycling performance. This work reveals that combining a three-dimensional carbon substrate with a core-shell structure might be a promising solution for anode materials with obvious volume transformation.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117768"},"PeriodicalIF":4.0,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434264","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}
Pub Date : 2024-10-10DOI: 10.1016/j.synthmet.2024.117766
Arindam Das, Indrani Chakraborti, Udayan Basak, Dhruba P. Chatterjee
Polyaniline (PANI) has received significant attention as conductive polymer owing to its simple and cost effective method of synthesis, light weight, environmentally benign nature etc. Furthermore, it offers many attractive features such as high conductivity, availability in different oxidation states, doping-dedoping using simple acid/base chemistry etc. Nanostructured PANI has been found to be even more impactful as single material or as component in composites. The mechanism behind oxidative polymerization of aniline is well researched and it has been found that supramolecular organization of the oligoanilines produced during aniline polymerization, dictates the fate of the final PANI chains. Thus, by judicious control over the structure as well as number of the oligomers, via manipulation of the polymerization parameters or by externally added oligomers, a significant degree of control over the PANI chain lengths, helicity or their morphology may be exercised. Besides generating potential polymeric chains of various utility, the oligomers themselves have been reported to be pretty effective in various similar applications. There are numerous reports and many reviews which explore the synthesis and applications of PANI chains and the role of oligoanilines. The present report revisits the recent progress in the field and further highlight the key role of the oligoanilines in design, synthesis and applications of PANI either as bulk material or composite component.
聚苯胺（PANI）因其合成方法简单、成本效益高、重量轻、对环境无害等特点，已成为备受关注的导电聚合物。此外，聚苯胺还具有许多吸引人的特性，如高导电性、不同氧化态的可用性、使用简单的酸碱化学进行掺杂等。人们发现，纳米结构的 PANI 作为单一材料或复合材料的成分，具有更大的影响力。人们对苯胺氧化聚合的机理进行了深入研究，发现苯胺聚合过程中产生的低聚苯胺的超分子组织决定了最终 PANI 链的命运。因此，通过操纵聚合参数或外部添加低聚物来明智地控制低聚物的结构和数量，可以在很大程度上控制 PANI 链的长度、螺旋度或其形态。据报道，低聚物本身除了可以生成各种用途的潜在聚合物链外，在各种类似应用中也相当有效。许多报告和评论都探讨了 PANI 链的合成和应用以及低聚苯胺的作用。本报告回顾了该领域的最新进展，并进一步强调了低聚苯胺在 PANI 的设计、合成和应用中的关键作用，无论是作为块状材料还是复合成分。
{"title":"Pivotal role of oligoanilines as regulator of polyaniline chain growth, helicity and overall morphology","authors":"Arindam Das, Indrani Chakraborti, Udayan Basak, Dhruba P. Chatterjee","doi":"10.1016/j.synthmet.2024.117766","DOIUrl":"10.1016/j.synthmet.2024.117766","url":null,"abstract":"<div><div>Polyaniline (PANI) has received significant attention as conductive polymer owing to its simple and cost effective method of synthesis, light weight, environmentally benign nature etc. Furthermore, it offers many attractive features such as high conductivity, availability in different oxidation states, doping-dedoping using simple acid/base chemistry etc. Nanostructured PANI has been found to be even more impactful as single material or as component in composites. The mechanism behind oxidative polymerization of aniline is well researched and it has been found that supramolecular organization of the oligoanilines produced during aniline polymerization, dictates the fate of the final PANI chains. Thus, by judicious control over the structure as well as number of the oligomers, via manipulation of the polymerization parameters or by externally added oligomers, a significant degree of control over the PANI chain lengths, helicity or their morphology may be exercised. Besides generating potential polymeric chains of various utility, the oligomers themselves have been reported to be pretty effective in various similar applications. There are numerous reports and many reviews which explore the synthesis and applications of PANI chains and the role of oligoanilines. The present report revisits the recent progress in the field and further highlight the key role of the oligoanilines in design, synthesis and applications of PANI either as bulk material or composite component.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117766"},"PeriodicalIF":4.0,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142530120","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}
The advantages of polyaniline for application in new generation solar cells include its cost-effectiveness, environmentally friendly synthesis, remarkable stability, and the ability to modify the bandgap through the synthesis of its nanocomposites. But a challenge for its nanostructures is the limited solubility in non-toxic solvents, including water, which limits their processability in coating techniques. We overcame this challenge by synthesizing its copolymer with diphenylamine-4-sulfonate and its nanocomposite with titanium dioxide nanoparticles (TiO2NPs). So through a solid-state and template-free technique and using sodium diphenylamine-4-sulfonate, aniline hydrochloride salt, TiO2NPs, and FeCl3∙6 H2O as an oxidant, poly(N-(sulfophenyl)aniline) nanoflowers (PSANFLs), poly [(aniline-co-N-(4-sulfophenyl) aniline] nanofibers (PAPSANFs), poly(N-(sulfophenyl)aniline) nanofibers/titanium dioxide nanoparticles (PSANFs/TiO2NPs), and poly (aniline-co-N-(4-sulfophenyl)aniline nanofibers/titanium dioxide nanoparticles (PAPSANFs/TiO2NPs) were synthesized. Characterization of the synthesized samples was carried out through field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectra, ultraviolet-visible spectra (UV-Vis), cyclic voltammetry (CV), and elemental analysis (CHNS). The FE-SEM images clearly illustrate that the synthesized samples are of nanoscale dimensions. The band gap values of 2.23 eV for PSANFs/TiO2NPs and 1.96 eV for PAPSANFs/TiO2NPs nanocomposites were determined through electrochemical calculations based on cyclic voltammetry curves, showcasing the complementary properties of n and p semiconductors. Using doctor blade method to prepare films from synthesized materials and the architectural pattern of ITO│TiO2NPs│semiconductor sample│Al, all hybrid solar cells are fabricated. The I-V characteristics and power conversion efficiency (PCE) of the samples were examined and discussed. The PCE values for the four samples were found to be in the range of 0.20–0.82 %.
{"title":"Mechanochemical synthesis and characterization of poly[(aniline-co-N-(4-sulfophenyl) aniline] nanofibers and its nanocomposite with titanium dioxide nanoparticles and study of their efficiency in hybrid solar cell","authors":"Mazaher Yarmohamadi-Vasel , Ali Reza Modarresi-Alam , Meissam Noroozifar , Sahar Shabzendedar , Saeid Gholizadeh , Edris Valadbeigi","doi":"10.1016/j.synthmet.2024.117767","DOIUrl":"10.1016/j.synthmet.2024.117767","url":null,"abstract":"<div><div>The advantages of polyaniline for application in new generation solar cells include its cost-effectiveness, environmentally friendly synthesis, remarkable stability, and the ability to modify the bandgap through the synthesis of its nanocomposites. But a challenge for its nanostructures is the limited solubility in non-toxic solvents, including water, which limits their processability in coating techniques. We overcame this challenge by synthesizing its copolymer with diphenylamine-4-sulfonate and its nanocomposite with titanium dioxide nanoparticles (TiO<sub>2</sub>NPs). So through a solid-state and template-free technique and using sodium diphenylamine-4-sulfonate, aniline hydrochloride salt, TiO<sub>2</sub>NPs, and FeCl<sub>3</sub>∙6 H<sub>2</sub>O as an oxidant, poly(N-(sulfophenyl)aniline) nanoflowers (<strong>PSANFLs</strong>), poly [(aniline-<em>co-N</em>-(4-sulfophenyl) aniline] nanofibers (<strong>PAPSANFs</strong>), poly(N-(sulfophenyl)aniline) nanofibers/titanium dioxide nanoparticles (<strong>PSANFs/TiO</strong><sub><strong>2</strong></sub><strong>NPs</strong>), and poly (aniline-<em>co-N</em>-(4-sulfophenyl)aniline nanofibers/titanium dioxide nanoparticles (<strong>PAPSANFs/TiO</strong><sub><strong>2</strong></sub><strong>NPs</strong>) were synthesized. Characterization of the synthesized samples was carried out through field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectra, ultraviolet-visible spectra (UV-Vis), cyclic voltammetry (CV), and elemental analysis (CHNS). The FE-SEM images clearly illustrate that the synthesized samples are of nanoscale dimensions. The band gap values of 2.23 eV for <strong>PSANFs/TiO</strong><sub><strong>2</strong></sub><strong>NPs</strong> and 1.96 eV for <strong>PAPSANFs/TiO</strong><sub><strong>2</strong></sub><strong>NPs</strong> nanocomposites were determined through electrochemical calculations based on cyclic voltammetry curves, showcasing the complementary properties of n and p semiconductors. Using doctor blade method to prepare films from synthesized materials and the architectural pattern of <strong>ITO│TiO</strong><sub><strong>2</strong></sub><strong>NPs│semiconductor sample│Al</strong>, all hybrid solar cells are fabricated. The I-V characteristics and power conversion efficiency (PCE) of the samples were examined and discussed. The PCE values for the four samples were found to be in the range of 0.20–0.82 %.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117767"},"PeriodicalIF":4.0,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434265","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}
Pub Date : 2024-10-09DOI: 10.1016/j.synthmet.2024.117765
Lokman Liv
A novel, simple, cost-effective, easy-to-prepare, and timesaving electrochemical sensor based on gold clusters decorated yellow 2 G polymer composite film was fabricated and comprehensively characterized for the determination of dopamine and nicotine in real samples. When gold clusters were modified on the yellow 2 G polymer film, a signal increase of 204 % for dopamine and 526 % for nicotine was obtained compared to the activated bare pencil graphite electrode. The signals at 90 mV for dopamine and 780 mV for nicotine were utilized as analytical responses. The fabricated platform serves noteworthy detection sensitivity values of 79.02 and 14.61 with a notable limit of detection values of 58.8 nM and 7.2 nM for dopamine and nicotine, respectively. The electrochemical method has linear ranges of 0.075–5 µM and 6–10 µM for dopamine alone, 0.01–10 µM and 12–25 µM for nicotine alone, 0.01–10 µM and 12–50 µM for nicotine in the presence of dopamine, 0.2–10 µM and 12–60 µM for dopamine in the presence of nicotine, and 0.4–2, 2–10 and 12–90 µM for dopamine and 0.2–8, 10–20 and 25–90 µM for nicotine at the increasing amounts of each substance. Moving forward, the developed method exhibits splendid accuracy and selectivity for determining dopamine and nicotine in biological samples of human saliva, serum, and urine.
{"title":"Catalytic competence of gold clusters decorated yellow 2 G polymer composite film for voltammetric sensing of dopamine and nicotine in biological fluids","authors":"Lokman Liv","doi":"10.1016/j.synthmet.2024.117765","DOIUrl":"10.1016/j.synthmet.2024.117765","url":null,"abstract":"<div><div>A novel, simple, cost-effective, easy-to-prepare, and timesaving electrochemical sensor based on gold clusters decorated yellow 2 G polymer composite film was fabricated and comprehensively characterized for the determination of dopamine and nicotine in real samples. When gold clusters were modified on the yellow 2 G polymer film, a signal increase of 204 % for dopamine and 526 % for nicotine was obtained compared to the activated bare pencil graphite electrode. The signals at 90 mV for dopamine and 780 mV for nicotine were utilized as analytical responses. The fabricated platform serves noteworthy detection sensitivity values of 79.02<span><math><mrow><mspace></mspace><mi>μ</mi><mi>A</mi><mo>.</mo><msup><mrow><mi>μ</mi><mi>M</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>.</mo><msup><mrow><mi>cm</mi></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup></mrow></math></span> and 14.61<span><math><mrow><mspace></mspace><mi>μ</mi><mi>A</mi><mo>.</mo><msup><mrow><mi>μ</mi><mi>M</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>.</mo><msup><mrow><mi>cm</mi></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup></mrow></math></span> with a notable limit of detection values of 58.8 nM and 7.2 nM for dopamine and nicotine, respectively. The electrochemical method has linear ranges of 0.075–5 µM and 6–10 µM for dopamine alone, 0.01–10 µM and 12–25 µM for nicotine alone, 0.01–10 µM and 12–50 µM for nicotine in the presence of dopamine, 0.2–10 µM and 12–60 µM for dopamine in the presence of nicotine, and 0.4–2, 2–10 and 12–90 µM for dopamine and 0.2–8, 10–20 and 25–90 µM for nicotine at the increasing amounts of each substance. Moving forward, the developed method exhibits splendid accuracy and selectivity for determining dopamine and nicotine in biological samples of human saliva, serum, and urine.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117765"},"PeriodicalIF":4.0,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434263","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}
Pub Date : 2024-10-02DOI: 10.1016/j.synthmet.2024.117761
Zhenchun Li , Yu Chang , Xiang Li , Junjie Lin , Wenhuan Wang , Qinghua Xia , Longfei Ruan , Cong Zhang , Xiao-Chun Hang
Tetradentate Pt(II) complexes, comprising of benzoimidazolyl N-heterocyclic carbene (BI-NHC) coordination, have shown superior performance in blue phosphorescent organic light-emitting diodes (PhOLEDs). Here, four frame-structured complexes were synthesized to explore the intrinsic ligand effect for rapid, efficient and narrow-spectra blue phosphorescence through experimental analyses and theoretical calculations. We found carbazolylpridine (CzPy) chelating part in Pt(II) BI-NHC complexes dominates the phosphorescence with the suppression of metal-centered transition and electron-vibration coupling. Consequently, the CzPy chelated complexes (PtN-dip and PtN-dtb) achieved high luminescent efficiency, rapid radiative decay rate (kr) and narrow emission spectra. The peripheral substituent 2,6-di-iso-propylphenyl (dip) on NHC of PtN-dip constrains the molecule, significantly reducing the non-radiative decay rate (knr) and enhancing the efficiency. The 3,5-di-tert-butylphenyl (dtb) in PtN-dtb could enhances low-frequency vibration coupling that could expedite the excitons decay, resulting in higher kr and knr. This work unveils the intrinsic factors behind the ligand effects of Pt(II) BI-NHC based complexes, leading to a rapid, efficient and narrow-spectra phosphorescence.
{"title":"Unveiling the ligand effects on Pt(Ⅱ) carbene complexes for rapid, efficient and narrow-spectra blue phosphorescence","authors":"Zhenchun Li , Yu Chang , Xiang Li , Junjie Lin , Wenhuan Wang , Qinghua Xia , Longfei Ruan , Cong Zhang , Xiao-Chun Hang","doi":"10.1016/j.synthmet.2024.117761","DOIUrl":"10.1016/j.synthmet.2024.117761","url":null,"abstract":"<div><div>Tetradentate Pt(II) complexes, comprising of benzoimidazolyl N-heterocyclic carbene (BI-NHC) coordination, have shown superior performance in blue phosphorescent organic light-emitting diodes (PhOLEDs). Here, four frame-structured complexes were synthesized to explore the intrinsic ligand effect for rapid, efficient and narrow-spectra blue phosphorescence through experimental analyses and theoretical calculations. We found carbazolylpridine (CzPy) chelating part in Pt(II) BI-NHC complexes dominates the phosphorescence with the suppression of metal-centered transition and electron-vibration coupling. Consequently, the CzPy chelated complexes (<strong>PtN-dip</strong> and <strong>PtN-dtb</strong>) achieved high luminescent efficiency, rapid radiative decay rate (<em>k</em><sub>r</sub>) and narrow emission spectra. The peripheral substituent 2,6-di-<em>iso</em>-propylphenyl (dip) on NHC of <strong>PtN-dip</strong> constrains the molecule, significantly reducing the non-radiative decay rate (<em>k</em><sub>nr</sub>) and enhancing the efficiency. The 3,5-di-<em>tert</em>-butylphenyl (dtb) in <strong>PtN-dtb</strong> could enhances low-frequency vibration coupling that could expedite the excitons decay, resulting in higher <em>k</em><sub>r</sub> and <em>k</em><sub>nr</sub>. This work unveils the intrinsic factors behind the ligand effects of Pt(II) BI-NHC based complexes, leading to a rapid, efficient and narrow-spectra phosphorescence.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117761"},"PeriodicalIF":4.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142426334","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}
Pub Date : 2024-10-02DOI: 10.1016/j.synthmet.2024.117764
Jiří Toušek , Jana Toušková , Ivo Křivka , Bita Ghasemi , Ivo Kuřitka , Pavel Urbánek
A diagnostic method based on the evaluation of low-frequency current fluctuation spectra is presented. When measuring the current through a p-type MEH-PPV sample, the occurrence of fluctuation is observable which can be measured with an AC amplifier. A model has been proposed that proves that the fluctuations originate from the interaction between the valence band and the band gap traps. The mean value of the amplitudes of these fluctuations increases linearly with decreasing frequency with a slope from which the product of mobility and lifetime of current carriers µpτp= (9 ± 3) × 10−15 cm2V−1 was obtained. The hole lifetime of (0.27 ± 0.01) ns was evaluated from the luminescence relaxation using the time-correlated single photon counting (TCSPC) technique. The mobility value (3 ± 1) × 10−5 cm2 V−1s−1 calculated using the above methods was compared with the mobility 1.8 × 10−5 cm2 V−1s−1 determined by the CELIV method (Charge extraction by linearly increasing voltage) and good agreement was obtained.
{"title":"The use of low-frequency current fluctuations in measuring the mobility of holes in the MEH-PPV polymer","authors":"Jiří Toušek , Jana Toušková , Ivo Křivka , Bita Ghasemi , Ivo Kuřitka , Pavel Urbánek","doi":"10.1016/j.synthmet.2024.117764","DOIUrl":"10.1016/j.synthmet.2024.117764","url":null,"abstract":"<div><div>A diagnostic method based on the evaluation of low-frequency current fluctuation spectra is presented. When measuring the current through a p-type MEH-PPV sample, the occurrence of fluctuation is observable which can be measured with an AC amplifier. A model has been proposed that proves that the fluctuations originate from the interaction between the valence band and the band gap traps. The mean value of the amplitudes of these fluctuations increases linearly with decreasing frequency with a slope from which the product of mobility and lifetime of current carriers <em>µ</em><sub><em>p</em></sub><em>τ</em><sub><em>p</em></sub> <em>=</em> (9 ± 3) × 10<sup>−15</sup> cm<sup>2</sup>V<sup>−1</sup> was obtained. The hole lifetime of (0.27 ± 0.01) ns was evaluated from the luminescence relaxation using the time-correlated single photon counting (TCSPC) technique. The mobility value (3 ± 1) × 10<sup>−5</sup> cm<sup>2</sup> V<sup>−1</sup>s<sup>−1</sup> calculated using the above methods was compared with the mobility 1.8 × 10<sup>−5</sup> cm<sup>2</sup> V<sup>−1</sup>s<sup>−1</sup> determined by the CELIV method (Charge extraction by linearly increasing voltage) and good agreement was obtained.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117764"},"PeriodicalIF":4.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142426386","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}
Pub Date : 2024-09-30DOI: 10.1016/j.synthmet.2024.117762
Changmin Lee , Sangwook Park , Hyukmin Kwon , Kiho Lee , Hayoon Lee , Seokwoo Kang , Dongmin Park , Jongwook Park
We designed new moieties with varying electron-donating effects and sizes based on diphenylamine and introduced them into anthracene to synthesize three types of emitting materials. All three materials exhibited high thermal stability with glass transition temperatures above 175°C, confirming their potential as OLED emitters. Devices doped with N9,N9,N10,N10-tetraphenylanthracene-9,10-diamine (TAD), where diphenyl amine is substituted on both sides, and N9,N10-di([1,1′-biphenyl]-4-yl)-N9,N10-bis(dibenzo[b,d]furan-2-yl)anthracene-9,10 diamine (ABFA), with a fused side group of diphenyl amine and dibenzofuran, showed EQEs of 1.28 % and 3.57 % respectively. Due to the intramolecular charge transfer (ICT), they exhibited ELmax values at 517 nm and 538 nm. On the other hand, the device doped with N,N′-(anthracene-9,10-diylbis(4,1-phenylene))bis(N-([1,1′-biphenyl]-4-yl)dibenzo[b,d]furan-2-amine) (APBFA), which has optimized side groups that suppress ICT and intermolecular packing, achieved a relatively high EQE of 4.48 % and showed blue emission with CIE coordinates of (0.146, 0.142).
{"title":"New blue emitters based on anthracene through charge transfer control","authors":"Changmin Lee , Sangwook Park , Hyukmin Kwon , Kiho Lee , Hayoon Lee , Seokwoo Kang , Dongmin Park , Jongwook Park","doi":"10.1016/j.synthmet.2024.117762","DOIUrl":"10.1016/j.synthmet.2024.117762","url":null,"abstract":"<div><div>We designed new moieties with varying electron-donating effects and sizes based on diphenylamine and introduced them into anthracene to synthesize three types of emitting materials. All three materials exhibited high thermal stability with glass transition temperatures above 175°C, confirming their potential as OLED emitters. Devices doped with N<sub>9</sub>,N<sub>9</sub>,N<sub>10</sub>,N<sub>10</sub>-tetraphenylanthracene-9,10-diamine (TAD), where diphenyl amine is substituted on both sides, and N<sub>9</sub>,N<sub>10</sub>-di([1,1′-biphenyl]-4-yl)-N<sub>9</sub>,N<sub>10</sub>-bis(dibenzo[<em>b</em>,<em>d</em>]furan-2-yl)anthracene-9,10 diamine (ABFA), with a fused side group of diphenyl amine and dibenzofuran, showed EQEs of 1.28 % and 3.57 % respectively. Due to the intramolecular charge transfer (ICT), they exhibited EL<sub>max</sub> values at 517 nm and 538 nm. On the other hand, the device doped with N,N′-(anthracene-9,10-diylbis(4,1-phenylene))bis(N-([1,1′-biphenyl]-4-yl)dibenzo[<em>b</em>,<em>d</em>]furan-2-amine) (APBFA), which has optimized side groups that suppress ICT and intermolecular packing, achieved a relatively high EQE of 4.48 % and showed blue emission with CIE coordinates of (0.146, 0.142).</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117762"},"PeriodicalIF":4.0,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142426333","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}
Pub Date : 2024-09-30DOI: 10.1016/j.synthmet.2024.117763
Shengna Liu , Baofeng Zhao , Weiping Wang , Liuchang Wang , Haimei Wu , Zhiyuan Cong , Guanghao Lu , Chao Gao
Polymer solar cells (PSCs) based on small molecules with twisted backbones as electron acceptors, have many advantages over their planar counterparts, such as upshifted molecular energy levels, better charge extraction performance, enhanced extinction coefficient, extended carrier lifetime and reduced recombination rate, which are very helpful in improving the power conversion efficiencies (PCE). The present study was designed to synthesize two new small molecules with main-chain twisted structures that include an asymmetric electron donor core thiophene-phenylene-thieno[3,2-b]thiophene, namely i-T-TT and i-T-TT-4F, to investigate the “structure-property” correlation of main-chain twisted acceptors. Both asymmetric molecules exhibit bent geometric structures, and the fluorinated acceptor i-T-TT-4F possesses a more red-shifted spectrum, improved molar extinction coefficient, and deepened molecular energy levels. As a result, when combined with the middle bandgap polymer donor J52, there was a remarkable efficiency of 12.22 % for the device of i-T-TT-4F, higher than that of i-T-TT (9.51 %). Our research illustrates the importance of the main-chain twisted asymmetric electron-donating core and fluorinated end-capping group in the construction of efficient PSCs.
{"title":"Asymmetric main-chain twisted small molecules for efficient polymer solar cells","authors":"Shengna Liu , Baofeng Zhao , Weiping Wang , Liuchang Wang , Haimei Wu , Zhiyuan Cong , Guanghao Lu , Chao Gao","doi":"10.1016/j.synthmet.2024.117763","DOIUrl":"10.1016/j.synthmet.2024.117763","url":null,"abstract":"<div><div>Polymer solar cells (PSCs) based on small molecules with twisted backbones as electron acceptors, have many advantages over their planar counterparts, such as upshifted molecular energy levels, better charge extraction performance, enhanced extinction coefficient, extended carrier lifetime and reduced recombination rate, which are very helpful in improving the power conversion efficiencies (PCE). The present study was designed to synthesize two new small molecules with main-chain twisted structures that include an asymmetric electron donor core thiophene-phenylene-thieno[3,2-<em>b</em>]thiophene, namely <strong>i-T-TT</strong> and <strong>i-T-TT-4F</strong>, to investigate the “structure-property” correlation of main-chain twisted acceptors. Both asymmetric molecules exhibit bent geometric structures, and the fluorinated acceptor <strong>i-T-TT-4F</strong> possesses a more red-shifted spectrum, improved molar extinction coefficient, and deepened molecular energy levels. As a result, when combined with the middle bandgap polymer donor J52, there was a remarkable efficiency of 12.22 % for the device of <strong>i-T-TT-4F</strong>, higher than that of <strong>i-T-TT</strong> (9.51 %). Our research illustrates the importance of the main-chain twisted asymmetric electron-donating core and fluorinated end-capping group in the construction of efficient PSCs.</div></div>","PeriodicalId":22245,"journal":{"name":"Synthetic Metals","volume":"309 ","pages":"Article 117763"},"PeriodicalIF":4.0,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142426302","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号