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1.
Nature ; 632(8025): 528-535, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39048826

RESUMEN

Conjugated polymers promise inherently flexible and low-cost thermoelectrics for powering the Internet of Things from waste heat1,2. Their valuable applications, however, have been hitherto hindered by the low dimensionless figure of merit (ZT)3-6. Here we report high-ZT thermoelectric plastics, which were achieved by creating a polymeric multi-heterojunction with periodic dual-heterojunction features, where each period is composed of two polymers with a sub-ten-nanometre layered heterojunction structure and an interpenetrating bulk-heterojunction interface. This geometry produces significantly enhanced interfacial phonon-like scattering while maintaining efficient charge transport. We observed a significant suppression of thermal conductivity by over 60 per cent and an enhanced power factor when compared with individual polymers, resulting in a ZT of up to 1.28 at 368 kelvin. This polymeric thermoelectric performance surpasses that of commercial thermoelectric materials and existing flexible thermoelectric candidates. Importantly, we demonstrated the compatibility of the polymeric multi-heterojunction structure with solution coating techniques for satisfying the demand for large-area plastic thermoelectrics, which paves the way for polymeric multi-heterojunctions towards cost-effective wearable thermoelectric technologies.

2.
Nat Mater ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112738

RESUMEN

Reusable point-of-care biosensors offer a cost-effective solution for serial biomarker monitoring, addressing the critical demand for tumour treatments and recurrence diagnosis. However, their realization has been limited by the contradictory requirements of robust reusability and high sensing capability to multiple interactions among transducer surface, sensing probes and target analytes. Here we propose a drug-mediated organic electrochemical transistor as a robust, reusable epidermal growth factor receptor sensor with striking sensitivity and selectivity. By electrostatically adsorbing protonated gefitinib onto poly(3,4-ethylenedioxythiophene):polystyrene sulfonate and leveraging its strong binding to the epidermal growth factor receptor target, the device operates with a unique refresh-in-sensing mechanism. It not only yields an ultralow limit-of-detection concentration down to 5.74 fg ml-1 for epidermal growth factor receptor but, more importantly, also produces an unprecedented regeneration cycle exceeding 200. We further validate the potential of our devices for easy-to-use biomedical applications by creating an 8 × 12 diagnostic drug-mediated organic electrochemical transistor array with excellent uniformity to clinical blood samples.

3.
BMC Cancer ; 24(1): 576, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730348

RESUMEN

OBJECTIVE: Nasopharyngeal adenoid cystic carcinoma (NACC) is a rare malignancy with special biological features. Controversies exist regarding the treatment approach and prognostic factors in the IMRT era. This study aimed to evaluate the long-term outcomes and management approaches in NACC. METHODS: Fifty patients with NACC at our institution between 2010 and 2020 were reviewed. Sixteen patients received primary radiotherapy (RT), and 34 patients underwent primary surgery. RESULTS: Between January 2010 and October 2020, a total of 50 patients with pathologically proven NACC were included in our analysis. The median follow-up time was 58.5 months (range: 6.0-151.0 months). The 5-year overall survival rate (OS) and progression-free survival rate (PFS) were 83.9% and 67.5%, respectively. The 5-year OS rates of patients whose primary treatment was surgery and RT were 90.0% and 67.3%, respectively (log-rank P = 0.028). The 5-year PFS rates of patients whose primary treatment was surgery or RT were 80.8% and 40.7%, respectively (log-rank P = 0.024). Multivariate analyses showed that nerve invasion and the pattern of primary treatment were independent factors associated with PFS. CONCLUSIONS: Due to the relative insensitivity to radiation, primary surgery seemed to provide a better chance of disease control and improved survival in NACC. Meanwhile, postoperative radiotherapy should be performed for advanced stage or residual tumours. Cranial nerve invasion and treatment pattern might be important factors affecting the prognosis of patients with NACC.


Asunto(s)
Carcinoma Adenoide Quístico , Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Humanos , Carcinoma Adenoide Quístico/radioterapia , Carcinoma Adenoide Quístico/mortalidad , Carcinoma Adenoide Quístico/patología , Carcinoma Adenoide Quístico/cirugía , Masculino , Femenino , Radioterapia de Intensidad Modulada/métodos , Persona de Mediana Edad , Adulto , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/mortalidad , Neoplasias Nasofaríngeas/patología , Anciano , Estudios Retrospectivos , Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/mortalidad , Carcinoma Nasofaríngeo/patología , Adulto Joven , Pronóstico , Tasa de Supervivencia , Resultado del Tratamiento , Estudios de Seguimiento , Adolescente , Supervivencia sin Progresión
4.
Angew Chem Int Ed Engl ; 63(20): e202320091, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38488855

RESUMEN

Conjugated coordination polymers (c-CPs) are unique organic-inorganic hybrid semiconductors with intrinsically high electrical conductivity and excellent charge carrier mobility. However, it remains a challenge in tailoring electronic structures, due to the lack of clear guidelines. Here, we develop a strategy wherein controlling the redox state of hydroquinone/benzoquinone (HQ/BQ) ligands allows for the modulation of the electronic structure of c-CPs while maintaining the structural topology. The redox-state control is achieved by reacting the ligand TTHQ (TTHQ=1,2,4,5-tetrathiolhydroquinone) with silver acetate and silver nitrate, yielding Ag4TTHQ and Ag4TTBQ (TTBQ=1,2,4,5-tetrathiolbenzoquinone), respectively. In spite of sharing the same topology consisting of a two-dimensional Ag-S network and HQ/BQ layer, they exhibit different band gaps (1.5 eV for Ag4TTHQ and 0.5 eV for Ag4TTBQ) and conductivities (0.4 S/cm for Ag4TTHQ and 10 S/cm for Ag4TTBQ). DFT calculations reveal that these differences arise from the ligand oxidation state inhibiting energy band formation near the Fermi level in Ag4TTHQ. Consequently, Ag4TTHQ displays a high Seebeck coefficient of 330 µV/K and a power factor of 10 µW/m ⋅ K2, surpassing Ag4TTBQ and the other reported silver-based c-CPs. Furthermore, terahertz spectroscopy demonstrates high charge mobilities exceeding 130 cm2/V ⋅ s in both Ag4TTHQ and Ag4TTBQ.

5.
J Am Chem Soc ; 145(4): 2430-2438, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36661343

RESUMEN

Electrically conductive coordination polymers and metal-organic frameworks are attractive emerging electroactive materials for (opto-)electronics. However, developing semiconducting coordination polymers with high charge carrier mobility for devices remains a major challenge, urgently requiring the rational design of ligands and topological networks with desired electronic structures. Herein, we demonstrate a strategy for synthesizing high-mobility semiconducting conjugated coordination polymers (c-CPs) utilizing novel conjugated ligands with D2h symmetry, namely, "4 + 2" phenyl ligands. Compared with the conventional phenyl ligands with C6h symmetry, the reduced symmetry of the "4 + 2" ligands leads to anisotropic coordination in the formation of c-CPs. Consequently, we successfully achieve a single-crystalline three-dimensional (3D) c-CP Cu4DHTTB (DHTTB = 2,5-dihydroxy-1,3,4,6-tetrathiolbenzene), containing orthogonal ribbon-like π-d conjugated chains rather than 2D conjugated layers. DFT calculation suggests that the resulting Cu4DHTTB exhibits a small band gap (∼0.2 eV), strongly dispersive energy bands near the Fermi level with a low electron-hole reduced effective mass (∼0.2m0*). Furthermore, the four-probe method reveals a semiconducting behavior with a decent conductivity of 0.2 S/cm. Thermopower measurement suggests that it is a p-type semiconductor. Ultrafast terahertz photoconductivity measurements confirm Cu4DHTTB's semiconducting nature and demonstrate the Drude-type transport with high charge carrier mobilities up to 88 ± 15 cm2 V-1 s-1, outperforming the conductive 3D coordination polymers reported till date. This molecular design strategy for constructing high-mobility semiconducting c-CPs lays the foundation for achieving high-performance c-CP-based (opto-)electronics.

6.
Small ; 19(29): e2300231, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37026675

RESUMEN

The thermoelectric (TE) performance of organic materials is limited by the coupling of Seebeck coefficient and electrical conductivity. Herein a new strategy is reported to boost the Seebeck coefficient of conjugated polymer without significantly reducing the electrical conductivity by incorporation of an ionic additive DPPNMe3 Br. The doped polymer PDPP-EDOT thin film exhibits high electrical conductivity up to 1377 ± 109 S cm-1 but low Seebeck coefficient below 30 µV K-1 and a maximum power factor of 59 ± 10 µW m-1 K-2 . Interestingly, incorporation of small amount (at a molar ratio of 1:30) of DPPNMe3 Br into PDPP-EDOT results in the significant enhancement of Seebeck coefficient along with the slight decrease of electrical conductivity after doping. Consequently, the power factor (PF) is boosted to 571 ± 38 µW m-1 K-2 and ZT reaches 0.28 ± 0.02 at 130 °C, which is among the highest for the reported organic TE materials. Based on the theoretical calculation, it is assumed that the enhancement of TE performance for the doped PDPP-EDOT by DPPNMe3 Br is mainly attributed to the increase of energetic disorder for PDPP-EDOT.

7.
Chemistry ; 29(43): e202301055, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37208940

RESUMEN

Low band gap materials have always been a focus of attention due to their potential applications in various fields. In this work, a series of asymmetric bistricyclic aromatic ene (BAE) compounds with fluorenylidene-cyclopentadithiophene (FYT) skeleton were facially synthesized, which were modified with different substituents (-OMe, -SMe). The FYT core exhibit twisted C=C bond with dihedral angles around 30°, and the introduction of -SMe group can provide additional S⋅⋅⋅S interaction between molecules, which is conducive to the charge transporting. The UV-Vis spectra, electrochemistry and photoelectron spectroscopy revealed that these compounds have relatively narrow band gaps, particularly, the -SMe modified compounds have slightly lower HOMO and Fermi energy levels than that of the -OMe modified compounds. Furthermore, PSCs devices were fabricated with the three compounds as HTMs, and FYT-DSDPA exhibit the best performance among them, revealing the fine-tuning band structure could influence properties of HTMs.

8.
Ann Pharmacother ; : 10600280231211306, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37960871

RESUMEN

BACKGROUND: Rivaroxaban and amiodarone are commonly used for treating patients with atrial fibrillation. Drug-drug interactions between rivaroxaban and amiodarone may increase exposure to rivaroxaban. However, the clinical relevance of this drug-drug interaction is still not clear. OBJECTIVE: The aim was to investigate the risk of bleeding in patients receiving a combination of rivaroxaban and amiodarone. METHODS: This was a prospective observational study in which we included atrial fibrillation patients treated with rivaroxaban. The patients were divided into the rivaroxaban group and the combination of rivaroxaban and amiodarone group (the combination group). Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were performed to adjust between-group differences. The primary endpoint was defined as the time to the first occurrence of a composite of major, clinically relevant nonmajor, and minor bleeding. RESULTS: In total, 481 atrial fibrillation patients were included in the analysis. After PSM, 154 patients in the rivaroxaban group were matched with 154 patients in the combination group. The bleeding events mainly consisted of clinically relevant nonmajor and minor bleeding. Only one patient experienced major bleeding. The primary outcome was recorded in 26.0% of patients in the combination group and 10.4% of patients in the rivaroxaban group (hazard ratio = 2.76, 95% CI = 1.55-4.93, P < 0.001). The bleeding risk was significantly higher in the combination group compared with that in the rivaroxaban group in the IPTW and stabilized IPTW analyses (hazard ratio = 2.17, 95% CI = 1.32-3.56, P = 0.002). CONCLUSION AND RELEVANCE: The combination of rivaroxaban and amiodarone increased the risk of bleeding in patients with atrial fibrillation, especially clinically relevant nonmajor and minor bleeding. Physicians prescribing rivaroxaban and amiodarone together should be concerned about an increase in the risk of nonmajor bleeding.

9.
Angew Chem Int Ed Engl ; 62(35): e202309073, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37427886

RESUMEN

Macroscopic compass-like magnetic alignment at low magnetic fields is natural for ferromagnetic materials but is seldomly observed in paramagnetic materials. Herein, we report a "paramagnetic compass" that magnetically aligns under ∼mT fields based on the single-crystalline framework constructed by lanthanide ions and organic ligands (Ln-MOF). The magnetic alignment is attributed to the Ln-MOF's strong macroscopic anisotropy, where the highly-ordered structure allows the Ln-ions' molecular anisotropy to be summed according to the crystal symmetry. In tetragonal Ln-MOFs, the alignment is either parallel or perpendicular to the field depending on the easiest axis of the molecular anisotropy. Reversible switching between the two alignments is realized upon the removal and re-adsorption of solvent molecules filled in the framework. When the crystal symmetry is lowered in monoclinic Ln-MOFs, the alignments become even inclined (47°-66°) to the field. These fascinating properties of Ln-MOFs would encourage further explorations of framework materials containing paramagnetic centers.

10.
Angew Chem Int Ed Engl ; 62(42): e202308146, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37632256

RESUMEN

The development of blue-emissive ambipolar organic semiconductor is an arduous target due to the large energy gap, but is an indispensable part for electroluminescent device, especially for the transformative display technology of simple-structured organic light-emitting transistor (SS-OLET). Herein, we designed and synthesized two new dibenzothiophene sulfone-based high mobility blue-emissive organic semiconductors (DNaDBSOs), which demonstrate superior optical property with solid-state photoluminescent quantum yield of 46-67 % and typical ambipolar-transporting properties in SS-OLETs with symmetric gold electrodes. Comprehensive experimental and theoretical characterizations reveal the natural of ambipolar property for such blue-emissive DNaDBSOs-based materials is ascribed to a synergistic effect on lowering LUMO level and reduced electron injection barrier induced by the interfacial dipoles effect on gold electrodes due to the incorporation of appropriate DBSO unit. Finally, efficient electroluminescence properties with high-quality blue emission (CIE (0.179, 0.119)) and a narrow full-width at half-maximum of 48 nm are achieved for DNaDBSO-based SS-OLET, showing good spatial control of the recombination zone in conducting channel. This work provides a new avenue for designing ambipolar emissive organic semiconductors by incorporating the synergistic effect of energy level regulation and molecular-metal interaction, which would advance the development of superior optoelectronic materials and their high-density integrated optoelectronic devices and circuits.

11.
Mol Genet Genomics ; 297(6): 1755-1765, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36152077

RESUMEN

The rise of the Tubo Kingdom is considered as the key period for the formation of modern groups on the Tibetan Plateau. The ethnic origin of the residents of the Tubo Kingdom is quite complex, and their genetic structure remains unclear. The tombs of the Tubo Kingdom period in Dulan County, Qinghai Province, dating back to the seventh century, are considered to be the remains left by Tubo conquerors or the Tuyuhun people dominated by the Tubo Kingdom. The human remains of these tombs are ideal materials for studying the population dynamics in the Tubo Kingdom. In this paper, we analyzed the genome-wide data of eight remains from these tombs by shotgun sequencing and multiplex PCR panels and compared the results with data of available ancient and modern populations across East Asia. Genetic continuity between ancient Dulan people with ancient Xianbei tribes in Northeast Asia, ancient settlers on the Tibetan Plateau, and modern Tibeto-Burman populations was found. Surprisingly, one out of eight individuals showed typical genetic features of populations from Central Asia. In summary, the genetic diversity of ancient Dulan people and their affiliations with other populations provide an example of the complex origin of the residents in the Tubo Kingdom and their long-distance connection with populations in a vast geographic region across ancient Asia.


Asunto(s)
ADN Antiguo , Genética de Población , Humanos , Tibet , Pueblo Asiatico/genética , Etnicidad , Variación Genética/genética
12.
Inorg Chem ; 61(12): 5060-5066, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35275484

RESUMEN

Construction of conductive coordination polymers (CPs) has already become an attractive strategy for the development of organic-inorganic hybrid functional materials with specific electrical performance, due to the great diversity and tunability of the chemical structures, electronic structures, as well as the functions they can offer. Here, we demonstrate a novel highly conductive CP based on silver (I) and benzenehexathiol (BHT), (Ag3BHT)n, which displays a different chemical stoichiometry and structural topology compared to the previously reported (Ag5BHT)n. Detailed structural analysis shows that this is caused by the unintentional oxidation of the ligand molecules during the CP formation process. (Ag3BHT)n displays an electrical conductivity of 39 S cm-1 at room temperature. Ultraviolet photoelectron spectroscopy characterization and density functional theory calculation reveal that its highly conducting behavior comes from the highly doped character of (Ag3BHT)n. In addition, band structure calculation proposed an unusual double Dirac cone. This work emphasizes the importance of the ligand oxidation strategy, which can greatly enrich the family of conductive CPs based on BHT and other noninnocent ligands.

13.
Cell Mol Biol Lett ; 27(1): 29, 2022 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-35305560

RESUMEN

BACKGROUND: Acute lung injury (ALI) has received considerable attention in the field of intensive care as it is associated with a high mortality rate. Obacunone (OB), widely found in citrus fruits, is a natural bioactive compound with anti-inflammatory and antioxidant activities. However, it is not clear whether OB protects against lipopolysaccharide (LPS)-induced ALI. Therefore, in this study, we aimed to evaluate the protective effects of OB and the potential mechanisms against LPS-induced ALI and BEAS-2B cell injury. METHODS: We established a model of BEAS-2B cell injury and a mouse model of ALI by treating with LPS. Samples of in vitro model were subjected to cell death, Cell Counting Kit-8, and lactate dehydrogenase (LDH) release assays. The total number of cells and neutrophils, protein content, and levels of IL-6, TNF-α, and IL-1ß were determined in bronchoalveolar lavage fluid (BALF). Glutathione, reactive oxygen species, and malondialdehyde levels were determined in lung tissue. Additionally, immunohistochemical analysis, immunofluorescence, western blot, quantitative real-time PCR, and enzyme-linked immunosorbent assay were conducted to examine the effects of OB. Furthermore, mice were treated with an Nrf2 inhibitor (ML385) to verify its role in ferroptosis. Data were analyzed using one-way analysis of variance or paired t-tests. RESULTS: Compared with the LPS group, OB effectively alleviated LPS-induced ALI by decreasing lung wet/dry weight ratio, reactive oxygen species and malondialdehyde production, and superoxide dismutase and glutathione consumption in vivo. In addition, OB significantly alleviated lung histopathological injury, reduced inflammatory cytokine secretion and Fe2+ and 4-HNE levels, and upregulated GPX4, SLC7A11, and Nrf2 expression. Mechanistically, OB activated Nrf2 by inhibiting Nrf2 ubiquitinated proteasome degradation. ML385 reversed the protective effects of OB against LPS-induced ALI. CONCLUSION: Overall, OB alleviates LPS-induced ALI, making it a potential novel protective agent against LPS-induced ALI.


Asunto(s)
Lesión Pulmonar Aguda , Ferroptosis , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Animales , Antioxidantes/farmacología , Benzoxepinas , Limoninas , Lipopolisacáridos/farmacología , Ratones , Factor 2 Relacionado con NF-E2/metabolismo
14.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36613799

RESUMEN

Honey bees are important managed pollinators that fulfill important ecological and economic functions. In recent decades, the obligate ectoparasite Varroa destructor severely affected the survival of honey bees, as it weakened them by different means. A common treatment against V. destructor is formic acid fumigation, which has been used for decades by beekeepers across the world. This treatment is known to be effective, but many beekeepers report adverse effects of formic acid on bees, which include damage to the brood, worker bee mortality, and queen loss. Little is known about the molecular mechanisms of formic acid detoxification in honey bees. Recently, we reported upregulation of the bee enzyme, 10-formyl-THFDH, under formic acid fumigation. Here, the active site of this enzyme is characterized by an interdisciplinary approach combining homology modeling and protein mutagenesis. In addition, the limitations of the 3D protein structure prediction program AlphaFold2 are shown in regard to docking studies. This study provides a more thorough understanding of the molecular detoxification mechanisms of formic acid in Apis mellifera.


Asunto(s)
Formiatos , Fumigación , Animales , Abejas , Dominio Catalítico
15.
Angew Chem Int Ed Engl ; 61(45): e202206825, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-35989244

RESUMEN

Organic semiconductors with combinative high carrier mobility and efficient solid-state emission are full of challenges but urgently pursued for developing new emerging optoelectronics. Herein, by delicately regulating the crystal packing of an anthracene-based molecular crystal via terminal tert-butylation, we developed a superior high mobility emissive molecule, 2,6-di(6-tert-butylnaphthyl)anthracene (TBU-DNA). The unique "slipped herringbone" packing motif of TBU-DNA enables its appropriate exciton-exciton coupling and electron-phonon coupling, thus resulting in remarkably high solid-state emission (photoluminescence quantum yield, ΦF ≈74.9 %) and efficacious charge transport (carrier mobility, µ=5.0 cm2 V-1 s-1 ). Furthermore, OLETs based on TBU-DNA show an external quantum efficiency (EQE) of 1.8 %, which is among the highest EQE values for single component OLETs reported till now. This work presents a crystal engineering strategy via exquisite molecular design to realize high mobility emissive organic semiconductors.

16.
J Am Chem Soc ; 143(42): 17526-17534, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34644063

RESUMEN

At the gas-liquid interface, the confined synthesis of metal-organic framework (MOF) films has been extensively developed by spreading an ultrathin oil layer on the aqueous surface as a reactor. However, this interface is susceptible to various disturbances and incapable of synthesizing large-area crystalline MOF films. Herein, we developed a polymer-assisted space-confined strategy to synthesize large-area films by blending poly(methyl methacrylate) (PMMA) into the oil layer, which improved the stability of the gas-liquid interface and the self-shrinkage of the oil layer on the water surface. Meanwhile, the as-synthesized MOFs as a quasi-solid substrate immobilized the edge of the oil layer, which maintained a large spreading area. Thanks to this synergistic effect, we synthesized the freestanding MOF-based film with a foot-level (0.66 ft) lateral dimension, which is the largest size reported so far. Besides, due to the phase separation of the two components, the MOF-PMMA composite film combined the conductivity of MOFs (1.13 S/m) with the flexibility of PMMA and exhibited excellent mechanical properties. More importantly, this strategy could be extended to the preparation of other MOFs, coordination polymers (CPs), and even inorganic material composite films, bringing light to the design and large-scale synthesis of various composite films for practical applications.

17.
Chem Soc Rev ; 49(20): 7210-7228, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-32975251

RESUMEN

Doping is essential to manipulate the electrical performance of both thermoelectric (TE) materials and organic semiconductors (OSCs). Although organic thermoelectric (OTE) materials have experienced a rapid development over the past decade, the chemical doping of OSCs for TE applications lags behind, which has limited further breakthroughs in this cutting-edge field. Recently, increasing efforts have been devoted to the development of energetically matched host and dopant molecules, exploring novel doping methods and revealing the doping mechanisms. This tutorial review covers the basic mechanisms, fundamental requirements, recent advances and remaining challenges of chemical doping in OSCs for TE applications. We first present the basic knowledge of the trade-off relationship in TE materials and its critical requirements for doped OSCs, followed by a brief introduction of recent advances in the molecular design of OSCs and dopants. Moreover, we provide an overview of the existing categories of doping mechanisms and methods, and more importantly, emphasize the summarized doping strategies for the state-of-the-art OTE materials. Finally, challenges and perspectives on the chemical doping of OSCs are proposed to highlight the research directions that deserve attention towards a bright future of OTE materials.

18.
Chemistry ; 26(16): 3578-3585, 2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-31774587

RESUMEN

Although cocrystallization has provided a promising platform to develop new organic optoelectronic materials, it is still a big challenge to purposely design and achieve specific optoelectronic properties. Herein, a series of mixed-stacking cocrystals (TMFA, TMCA, and TMTQ) were designed and synthesized, and the regulatory effects of the acceptors on the co-assembly behavior, charge-transfer nature, energy-level structures, and optoelectronic characteristics were systematically investigated. The results demonstrate that it is feasible to achieve effective charge-transport tuning and photoresponse switching by carefully regulating the intermolecular charge transfer and energy orbitals. The inherent mechanisms underlying the change in these optoelectronic behaviors were analyzed in depth and elucidated to provide clear guidelines for future development of new optoelectronic materials. In addition, due to the excellent photoresponsive characteristics of TMCA, TMCA-based phototransistors were investigated with varying light wavelength and optical power, and TMCA shows the best performance among all reported cocrystals under UV illumination.

19.
Macromol Rapid Commun ; 41(1): e1900322, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31531908

RESUMEN

Four conjugated polymers are synthesized through indacenodithiohene (IDT) unit copolymerized with thiophene and thiophene derivatives. Indacenodithiohene-co-thieno[3,2-b]thiophene (IDT-TT) and indacenodithiohene-co-trans-1,2-di(2-thienyl)ethylene (IDT-TVT) exhibit better charge transport mobilities than indacenodithiohene-co-thiophene (IDT-T) and indacenodithiohene-co-3,4-ethoxylene dioxythiophene (IDT-EDOT), and also display superior thermoelectric properties after doping. Theoretical calculations suggest that IDT-EDOT and IDT-TVT have better coplanarities; the inferior performance for IDT-EDOT might be due to its low molecular weight. Meanwhile, it is worth mentioning that via the synergistic effect of two dopants (CN6CP, CuTFSI), the electrical conductivities of the polymers are further improved. The XPS data shows that the coordination interaction between copper ion and the cyano groups of CN6CP introduces cupric ions into the polymer films, which leads to the increase of the doping ratio.


Asunto(s)
Polímeros/química , Tiofenos/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Cobre/química , Cianuros/química , Conductividad Eléctrica , Polimerizacion , Teoría Cuántica
20.
Angew Chem Int Ed Engl ; 59(24): 9403-9407, 2020 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-32196849

RESUMEN

Preparing two-dimensional conjugated polymers (2DCPs) with desirable structures and semiconducting properties is promising but remains a great challenge. Presented here is a new 2DCP, named 2D polytriethyltriindole (2DPTTI), which is efficiently synthesized by a modified interfacial Suzuki reaction from 2,7,12-tribromo-5,10,15-triethyltriindole (2-BrTTI) and 1,4-benzenediboronic acid dipinacol ester (BADE) precursors at room temperature. Wafer-scale free-standing 2DPTTI films with controllable thicknesses between 2.5 and 46.0 nm were obtained by adjusting the experimental conditions. The resulting 2DPTTI films, used as an active layer in organic field effect transistors (OFETs), exhibited typical p-type semiconducting properties and superior UV optoelectronic performance with a photosensitivity of 3.7×103 and responsivity of 1.4×103  A W-1 , as well as a light-blue fluorescence character. This report provides a general approach for constructing various semiconducting 2DCPs, by an interfacial Suzuki reaction, towards multifunctional organic electronics.

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