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1.
Chemistry ; 30(10): e202302552, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-37997029

RESUMO

This work demonstrated the first synthetic application of direct C-H olefinations in the step-saving preparation of various hole-transporting materials (HTM) for efficient perovskite solar cells (PSC). Cross-dehydrogenative couplings of naphthodithiophene (NDT) with vinyl arenes under palladium-catalysis facilely generated various new oligo(hetero)aryls with internal alkenes. Reaction conditions were optimized, which gave the product isolated yields of up to 71 % with high (E)-stereoselectivity. These readily accessible NDT core-based small molecules involving olefin as π-spacers displayed immediate power conversion efficiencies of up to 17.2 % without a device oxidation process that is required for the commercially available spiro-OMeTAD and most other existing HTMs while fabricated in corresponding PSC devices.

2.
Chem Commun (Camb) ; 59(99): 14653-14656, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37991800

RESUMO

A new class of fluorinated cyclopenta[2,1-b:3,4-b']dithiophene (CPDT)-based small molecules, namely YC-oF, YC-mF, and YC-H, are demonstrated as hole-transporting materials (HTMs) for high-performance perovskite solar cells (PSCs). PSCs employing YC-oF as the HTM delivered an excellent efficiency of 22.41% with encouraging long-term stability.

3.
Chem Asian J ; 18(20): e202300681, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37694942

RESUMO

In this work, we have successfully synthesized 15 new examples (LLA01-06; LinLi01-10) of small-molecule hole-transporting materials (HTM) using the less explored indolocarbazole (ICbz) as core moiety. Different from previously reported ICbz HTMs, LinLi01-10 exhibit new molecular designs in which 3,4-ethylenedioxythiophene (EDOT) units are inserted as crucial π-spacers and fluorine atoms are introdcued into end-group molecules. These substantially improve the materials solubility and device power conversion efficiencies (PCEs) while fabricated in perovskite solar cells (PSC). More importantly, LinLi01-10 are generated by a sustainable synthetic approach involving the use of straightforward C-H/C-Br couplings as key transformations, thus avoiding additional synthetic transformations including halogenation and borylation reactions called substrate prefunctionalizations usually required in Suzuki reactions. Most HTM molecules can be purified simply by reprecipitations instead of conducting column chromatography. In contrast to LLA01-06 without additional EDOT moieties, PSC devices using LinLi01-10 as hole-transport layers display promising PCEs of up to 17.5 %. Interestingly, PSC devices employing seven of the LinLi01-10 as hole-transport molecules, respectively, are all able to show an immediate >10 % PCE (t=0) without any device oxidation/aging process that is necessary for the commercial spiro-OMeTAD based PSCs.

4.
Sensors (Basel) ; 22(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36433450

RESUMO

The fluorescence intensity of inorganic CsPbBr3 (CPB) perovskite nanocrystals (NCs) decreases in the presence of O2. In this study, we synthesized CPB NCs with various shapes and sizes for use as optical gas sensing materials. We fabricated O2 gas sensors from the various CPB NCs on several porous and nonporous substrates and examined the effects of the NC shapes and aggregate sizes and the substrate pore size on the device response. Our sensor fabricated from CPB nanocrystals on a porous substrate exhibited the highest response; the porous substrate allowed the rapid diffusion of O2 such that the NC surface was exposed effectively to the gas. Thus, the interfacial interaction between NC surfaces and substrates is a critical factor for consideration when preparing gas sensors with a high response.

5.
Nanomaterials (Basel) ; 12(15)2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35957082

RESUMO

In recent years, additive engineering has received considerable attention for the fabrication of high-performance perovskite solar cells (PSCs). In this study, a non-ionic surfactant, polyoxyethylene (20) sorbitan monolaurate (Tween 20), was added as an additive into the MAPbI3 perovskite layer, and the thermal-assisted blade-coating method was used to fabricate a high-quality perovskite film. The Tween 20 effectively passivated defects and traps in the MAPbI3 perovskite films. Such a film fabricated with an appropriate amount of Tween 20 on the substrate showed a higher photoluminescence (PL) intensity and longer carrier lifetime. At the optimal concentration of 1.0 mM Tween 20, the performance of the PSC was apparently enhanced, and the champion PSC demonstrated a PCE of 18.80%. Finally, this study further explored and compared the effect on the device performance and ambient stability of the MAPbI3 perovskite film prepared by the spin-coating method and the thermal-assisted blade coating.

7.
Emerg Microbes Infect ; 11(1): 1867-1875, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35811508

RESUMO

Candida auris, a multidrug resistant pathogenic yeast, has spread worldwide and caused several outbreaks in healthcare settings. Here, we report the first case of C. auris candidemia in Taiwan in a patient with a two-month history of hospitalization in Vietnam. We performed further investigation on the isolate from the present case as well as the previously reported C. auris isolate identified from a wound in 2018 in Taiwan, which was the first case reported in Taiwan. Both C. auris isolates were found to be susceptible to fluconazole, amphotericin B, and echinocandins. Additionally, mutations in ERG11 or FKS1 were not detected in either isolate. Microsatellite genotyping revealed that both isolates belonged to the South Asian clade. In recent years, C. auris has emerged as a global concern, and differences in clades and susceptibility patterns mandate further awareness and systematic surveillance.


Assuntos
Candida auris , Candidíase Invasiva , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida/genética , Candidíase , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Taiwan/epidemiologia
8.
Polymers (Basel) ; 14(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35458333

RESUMO

In this work, two novel tetra-substituted X-shaped molecules X1 and X2 that were constructed with anthracene as the central core and arylamine as the donor groups have been synthesized. The HTMs X1 and X2 were synthesized in two steps from industrially accessible and moderately reasonable beginning reagents. These new HTMs are described in terms of utilization of light absorption, energy level, thermal properties, hole mobility (µh), and film-forming property. The photovoltaic performances of these HTMs were effectively assessed in perovskite solar cells (PSCs). The devices based on these HTMs accomplished an overall efficiency of 16.10% for X1 and 10.25% for X2 under standard conditions (AM 1.5 G and 100 mW cm-2). This precise investigation provides another perspective on the use of HTMs in PSCs with various device configurations.

9.
Polymers (Basel) ; 13(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34883754

RESUMO

In this study, polycaprolactone (PCL)- and poly(acrylic acid) (PAA)-based electrospun nanofibers were prepared for the carriers of antimicrobials and designed composite nanofiber mats for chronic wound care. The PCL- and PAA-based electrospun nanofibers were prepared through in situ polymerization starting from PCL and acrylic acid (AA). Different amounts of AA were introduced to improve the hydrophilicity of the PCL electrospun nanofibers. A compatibilizer and a photoinitiator were then added to the electrospinning solution to form a grafted structure composed of PCL and PAA (PCL-g-PAA). The grafted PAA was mainly located on the surface of a PCL nanofiber. The optimization of the composition of PCL, AA, compatibilizer, and photoinitiator was studied, and the PCL-g-PAA electrospun nanofibers were characterized through scanning electron microscopy and 1H-NMR spectroscopy. Results showed that the addition of AA to PCL improved the hydrophilicity of the electrospun PCL nanofibers, and a PCL/AA ratio of 80/20 presented the best composition and had smooth nanofiber morphology. Moreover, poly[2 -(tert-butylaminoethyl) methacrylate]-grafted graphene oxide nanosheets (GO-g-PTA) functioned as an antimicrobial agent and was used as filler for PCL-g-PAA nanofibers in the preparation of composite nanofiber mats, which exerted synergistic effects promoted by the antibacterial properties of GO-g-PTA and the hydrophilicity of PCL-g-PAA electrospun nanofibers. Thus, the composite nanofiber mats had antibacterial properties and absorbed body fluids in the wound healing process, thereby promoting cell proliferation. The biodegradation of the PCL-g-PAA electrospun nanofibers also demonstrated an encouraging result of three-fold weight reduction compared to the neat PCL nanofiber. Our findings may serve as guidelines for the fabrication of electrospun nanofiber composites that can be used mats for chronic wound care.

10.
Viruses ; 13(11)2021 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-34835138

RESUMO

Norovirus-associated diseases are the most common foodborne illnesses worldwide. Polymerase chain reaction-based methods are the primary diagnostics for clinical samples; however, the high mutation rate of norovirus makes viral amplification and genotyping challenging. Technological advances in mass spectrometry (MS) make it a promising tool for identifying disease markers. Besides, the superior sensitivity of MS and proteomic approaches may enable the detection of all variants. Thus, this study aimed to establish an MS-based system for identifying and typing norovirus. We constructed three plasmids containing the major capsid protein VP1 of the norovirus GII.4 2006b, 2006a, and 2009a strains to produce virus-like particles for use as standards. Digested peptide signals were collected using a nano-flow ultra-performance liquid chromatography mass spectrometry (nano-UPLC/MSE) system, and analyzed by ProteinLynx Global SERVER and TREE-PUZZLE software. Results revealed that the LC/MSE system had an excellent coverage rate: the system detected more than 94% of amino acids of 3.61 femtomole norovirus VP1 structural protein. In the likelihood-mapping analysis, the proportions of unresolved quartets were 2.9% and 4.9% in the VP1 and S domains, respectively, which is superior to the 15.1% unresolved quartets in current PCR-based methodology. In summary, the use of LC/MSE may efficiently monitor genotypes, and sensitively detect structural and functional mutations of noroviruses.


Assuntos
Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/isolamento & purificação , Norovirus/classificação , Sorotipagem/métodos , Humanos , Japão/epidemiologia
11.
Nanomaterials (Basel) ; 11(8)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443958

RESUMO

Nowadays, a dye-sensitized solar cell (DSSC) attracts attention to its development widely due to its several advantages, such as simple processes, low costs, and flexibility. In this work, we demonstrate the difference in device structures between small size and large size cells (5 cm × 5 cm, 10 cm × 10 cm and 10 cm × 15 cm). The design of the photoanode and dye-sensitized process plays important roles in affecting the cell efficiency and stability. The effects of the TiO2 electrode, using TiCl4(aq) pretreatment and post-treatment processes, are also discussed, whereas, the open-circuit voltage (Voc), short-circuit current density (Jsc), and module efficiency are successfully improved. Furthermore, the effects on module performances by some factors, such as dye solution concentration, dye soaking temperature, and electrolyte injection method are also investigated. We have demonstrated that the output power of a 5 cm × 5 cm DSSC module increases from 86.2 mW to 93.7 mW, and the module efficiency achieves an outstanding performance of 9.79%. Furthermore, enlarging the DSSC modules to two sizes (10 cm × 10 cm and 10 cm × 15 cm) and comparing the performance with different module designs (C-DSSC and S-DSSC) also provides the specific application of polymer sealing and preparing high-efficiency large-area DSSC modules.

12.
Nanomaterials (Basel) ; 11(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207375

RESUMO

This study improved quality of CH3NH3PbI3 (MAPbI3) perovskite films by delaying thermal annealing in the spin coating process and introducing KI and I2 to prepare MAPbI3 films that were low in defects for high-efficiency perovskite solar cells. The influences of delayed thermal annealing time after coating the MAPbI3 perovskite layer on the crystallized perovskite, the morphology control of MAPbI3 films, and the photoelectric conversion efficiency of solar cells were investigated. The optimal delayed thermal annealing time was found to be 60 min at room temperature. The effect of KI/I2 additives on the growth of MAPbI3 films and the corresponding optimal delayed thermal annealing time were further investigated. The addition of KI/I2 can improve perovskite crystallinity, and the conductivity and carrier mobility of MAPbI3 films. Under optimized conditions, the photoelectric conversion efficiency of MAPbI3 perovskite solar cells can reach 19.36% under standard AM1.5G solar illumination of 100 mW/cm2.

13.
Chem Commun (Camb) ; 57(52): 6444-6447, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34096942

RESUMO

A new cyclopentadithiophene (CPDT)-based organic small molecule serves as an efficient dopant-free hole transport material (HTM) for perovskite solar cells (PSCs). Upon incorporation of two carbazole groups, the resulting CPDT-based HTM (C-CPDT) shows an impressive power conversion efficiency (PCE) of 19.68% with better stability compared with those of spiro-OMeTAD.

14.
Chem Rec ; 21(12): 3498-3508, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33955155

RESUMO

Synthetic organic chemists endeavor to develop new reaction conditions, improve product yields, and enhance atom economy (synthetic methodologies), whereas the material scientists strive to create novel functional molecules/structures, increase device stabilities, and promote power conversion efficiencies via device engineering (organic optoelectronics). However, these two prominent research fields seem to have no intersections. Since joining national central university in 2012, our research philosophy aims to narrow, or rather to bridge the gap between synthetic methodologies and π-functional organic materials. In contrast to using multistep synthetic approaches based on Suzuki- or Stille coupling reactions, this personal account describes various step-saving and viable synthesis-shortcuts developed by our group, to access thiophene-based small molecules for optoelectronic applications. We expect these succinct and user-friendly alternative pathways designed by synthetic chemists would help material scientists to reach their target molecules in a more step-economical manner.


Assuntos
Estrutura Molecular , Humanos
15.
Anaerobe ; 69: 102327, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33515721

RESUMO

Anaerobiospirillum succiniciproducens is a gram-negative, spiral-shaped anaerobe, that is a rare but potentially lethal cause of bacteremia in humans, particularly in immunocompromised hosts. We reported a 69-year-old HIV-infected male presenting with dysphagia, odynophagia and fulminant pneumonia who died. In addition, in a literature review, we summarized the characteristics of 19 adult patients with A. succiniciproducens bacteremia, which were confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry or molecular methods. Among those, the presentation of gastrointestinal conditions was the only independent risk factor for mortality. Clinicians should be aware of this pathogen, especially when a culture is negative but a Gram stain reveals gram-negative spiral-shaped bacteria.


Assuntos
Anaerobiospirillum/genética , Anaerobiospirillum/isolamento & purificação , Anaerobiospirillum/patogenicidade , Infecções por Bactérias Gram-Negativas/etiologia , Infecções por HIV/sangue , Infecções por HIV/complicações , Infecções por HIV/microbiologia , Idoso , Evolução Fatal , Infecções por Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/mortalidade , Infecções por HIV/mortalidade , Humanos , Masculino , Taiwan
16.
RSC Adv ; 11(15): 8879-8885, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35423386

RESUMO

In most research papers, synthesis of organic hole-transporting materials relies on a key-reaction: Stille cross-couplings. This requires tedious prefunctionalizations including the preparation and treatment of unstable organolithium and toxicity-concern organotin reagents. In contrast to traditional multistep synthesis, this work describes that a series of star-shaped small molecules with a carbazole or phenothiazine core can be efficiently synthesized through a shortcut using optimized direct C-H/C-Br cross-couplings as the key step, thus avoiding dealing with the highly reactive organolithium or the toxic organotin species. Device fabrication of perovskite solar cells employing these molecules (6-13) as hole-transporting layers exhibit promising power conversion efficiencies of up to 17.57%.

17.
ACS Appl Mater Interfaces ; 12(45): 50495-50504, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33112130

RESUMO

Two polycyclic heteroarene derivatives, namely, V-1 and V-2, with a diphenanthro[9,10-b:9',10'-d]thiophene (DPT) core tethered with two diphenylaminophenyl or diphenylamino groups were first synthesized and used as hole-transporting materials (HTMs) in perovskite solar cell (PSC) fabrication. The novel HTMs exhibit appropriate energy-level alignment with the perovskite so as to ensure efficient hole transfer from the perovskite to HTMs. V-2 with the diphenylamino substituent on DPT exhibited impressive photovoltaic performance with a power conversion efficiency of 19.32%, which was higher than that of V-1 (18.60%) and the benchmark 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenyl-amine)-9,9'-spirobifluorene (spiro-OMeTAD) (17.99%), presumably because of a better hole extraction, higher hole mobility, and excellent film-forming ability, which were supported by steady-state photoluminescence (PL), time-resolved PL, the hole mobility experiment, scanning electron microscopy, and atomic force microscopy measurements. Meanwhile, V-2-based PSCs exhibited better long-term durability than that with V-1 and the state-of-the-art spiro-OMeTAD, which is ascribable to the excellent surface morphology and hydrophobicity of the film. This systematic study suggests that DPT-based molecules are good potential candidates as HTMs for achieving high-performance PSCs.

18.
Small ; 16(41): e2002201, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32954669

RESUMO

Perovskite solar cells (PSCs) have become one of the most promising renewable energy converting devices. However, in order to reach a sufficiently high power conversion efficiency (PCE), the PSCs typically require a high-temperature sintering process to prepare mesostructured TiO2 as an efficient electron transport layer (ETL), which prohibits the PSCs from commercialization in the future. This work investigates a low-temperature synthesis of TiO2 nanocrystals and introduces a two-fluid spray coating process to produce a nanostructured ETL for the following deposition of perovskite layer. The temperature during the whole deposition process can be maintained under 150 °C. Compared to the typical planar TiO2 layer, the perovskite layer fabricated on a nanostructured TiO2 layer shows uniform compactness, preferred orientation, and high crystallinity, leading to reproducible and promising device performance. The detail mechanisms are revealed by the contact angle test, morphology characterization, grazing incident wide angle X-Ray scattering measurement, and space charge limited currents analysis. Finally, optimized device performance can be achieved through adequate Zn doping in the TiO2 layer, demonstrating an average PCE of 19.87% with champion PCE of 21.36%. The efficiency can maintain over 80% of its original value after 3000 h storage in ambient atmosphere. This study suggests a promising approach to offer high-efficiency PSCs using the low-temperature process.

19.
Polymers (Basel) ; 12(7)2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32605222

RESUMO

A novel cationic polymer, poly[2-(tert-butylaminoethyl) methacrylate] (PTA), effectively kills various strains of bacteria with low toxicity to tissue cells. Graphene-based materials demonstrate exceptional electron transport capability, antibacterial activity, favorable nontoxicity, and versatile applicability. PTA can be grafted onto the graphene oxide (GO) surface (GO-g-PTA) to enhance the antimicrobial efficiency of the latter against Staphylococcus aureus (S. aureus). In this study, GO-g-PTA powders were successfully synthesized via free radical polymerization (GO-g-PTA-F) and atom transfer radical polymerization (GO-g-PTA-A). The antimicrobial efficiencies of graphene nanosheets (GNSs), GO-g-PTA-F, and GO-g-PTA-A were then investigated. Addition of GNS, GO-g-PTA-F, and GO-g-PTA-A to the PVA nanofibers was carried out elucidate the effects of filler amount and physical treatment on the morphology, microstructure, crystallization behaviors, antimicrobial efficiency, and cytotoxicity of the composite fibers. Finally, the potential applications of electrospun PVA/GNS, PVA/GO-g-PTA-F, and PVA/GO-g-PTA-A composite nanofiber mats to chronic wound care were evaluated. The resulting PVA/GO-g-PTA-A composite nanofiber mats showed enhanced antimicrobial ability against S. aureus compared with the PVA/GNS and PVA/GO-g-PTA-F composite nanofiber mats at the same filler volume percentage.

20.
ACS Appl Mater Interfaces ; 12(23): 26041-26049, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32434322

RESUMO

Low-cost and solution-processed perovskite solar cells have shown great potential for scaling-up mass production. In comparison with the spin coating process for fabricating devices with small areas, the blade coating process is a facile technique for preparing uniform films with large areas. High-efficiency perovskite solar cells have been reported using blade coating, but they were fabricated using the toxic solvent N,N-dimethylformide (DMF) in nitrogen. In this work, we present highly efficient blade-coated perovskite solar cells prepared using a green solvent mixture of γ-butyrolactone (GBL) and dimethyl sulfoxide (DMSO) in an ambient environment. By carefully controlling the interface, morphology, and crystallinity of perovskite films through composition variations and additives, a high power conversion efficiency of 17.02% is achieved in air with 42.4% reduction of standard deviation in performance. The findings in this work resolve the issues of scalability and solvent toxicity; thus, the mass production of perovskite solar cells becomes feasible.

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