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101.
Fei Dou Cephas Small Francoise Provencher Jason Ferreira Xuhua Wang Elham Rezasoltani Hongmei Liu Xinping Zhang 《Journal of Polymer Science.Polymer Physics》2017,55(12):940-947
We investigate the influence of particle plasmons on exciton and charge generation and recombination processes in the blend of poly (9‐(1‐octylnonyl)‐9H‐carbazole‐benzothiadiazole‐4,7‐diyl‐2,5‐thiophenediyl) (PCDTBT) and [6,6]‐phenyl‐C70butyric acid methyl ester (PC70BM). The particle plasmons are generated from gold nanoparticles, which are embedded into PCDTBT:PC70BM blend. For the blend with gold nanoparticles, we observe enhance light harvesting. Despite the enhanced light collection, we find that the quasi‐steady‐state charge generation has not been influenced by the particle plasmons. However, the generation and recombination of long‐lived (sub‐millisecond) polaron paris have been significantly enhanced: from untrapped state in the pristine blend to the trapped state in the gold nanoparticle‐embedded blend. This result implies that the plasmon‐influenced polarons are trapped at the broadband geminate polaron pair (GPP) state. This state acts as an intermediate state, which either leads to the formation of charge transfer excitons (CTXs) or free charge carriers. In our case, the particle plasmon‐influenced polarons are trapped in the GPP state, which leads to the formation of CTXs. For this reason, we do not observe the enhanced charge generation in PCDTBT:PC70BM blend with particle plasmon resonance. Finally, we revealed that the long‐lived polarons mainly resulted from the localization by particle plasmons. The macroscopic modification in the blend film made negligible contributions to this influence. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 940–947 相似文献
102.
A copper metal–organic framework nanoparticles (Cu‐MOF‐NPs) synthesized via simple technique. The prepared Cu‐MOF‐NPs nanoparticles were further characterized using 1H‐NMR, FE‐SEM/EDX and thermal study (DSC/TGA). The FE‐SEM/EDX, thermal analysis, and NMR spectrum data with the other analysis support the nano‐Cu‐MOF structure and the monomeric unit (n[Cu (AIP)2(APY)(H2O)2].4H2O) of Cu‐MOF‐NPs. The photoluminescence (PL) studies of triiodothyronine hormone (T3) based on the prepared Cu‐MOF‐NPs investigated. The results revealed that the Cu‐MOF‐NPs might be used as a biosensor in the determination of triiodothyronine hormone (T3) in biological fluids through a significant quenching of the photoluminescence intensity of Cu‐MOF‐NPs at excitation wavelength 492 nm. The calibration plot achieved over the concentration range 0.0–200.0 ng/dL T3 hormone with a correlation coefficient 0.996 and limit of detection (LOD) and quantification (LOQ) 0.198 and 0.60 ng/dL, respectively. The PL spectra are indicating that Cu‐MOF‐NPs has highly selective sensing properties for T3 hormone without interfering with other human many hormones types. This approach considered a promising analytical tool for early diagnosis of the cases of thyroid disease. The mechanism of quenching between the Cu‐MOF‐NPs, and T3 hormone studied. The mechanism was a dynamic type and obtained due to the energy transfer mechanism. 相似文献
103.
Our group has developed a series of molecular electrocatalysts for hydrogen generation based on triazenido–metal complexes (cobalt, copper, etc.). In this paper, we first present the electrocatalytic performance of a new dinuclear silver complex, [Ag2(L)2], formed by the reaction of the triazenido ligand 1‐[(2‐carboxymethyl)benzene]‐3‐[(2‐methoxy)benzene]triazene (HL) with AgNO3. At room temperature, the silver complex shows photoluminescence at 653 nm. The electrocatalytic systems based on this silver complex can afford 106.57 and 1536.36 moles of hydrogen per mole of catalyst per hour from acetic acid at an overpotential (OP) of 991.6 mV and from a neutral aqueous buffer (pH = 7.0) at an OP of 837.6 mV, respectively. Electrochemical investigations show that both silver ion and triazenido ligand play a role in determining the catalytic activities of the electrocatalytic system. 相似文献
104.
Dr. Ning Chen Dr. Yanglin Shen Dr. Ting Xu Dr. Wangqiang Shen Prof. Xing Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16212-16218
Surface cracks could improve the optical and photoelectronic properties of crystalline materials as they increase specific surface area, but the controlled self-assembly of fullerene (C60) molecules into micro-/nanostructures with surface cracks is still challenging. Herein, we report the morphology engineering of novel C60 microstructures bearing surface cracks for the first time, selecting phenetole and propan-1-ol (NPA) as good and poor solvents, respectively. Our systematic investigations reveal that phenetole molecules initially participate in the formation of the ends of the C60 microstructures, and then NPA molecules are involved in the gradual growth of the sidewalls of the microstructures. Therefore, the surface cracks of C60 microstructures can be finely regulated by adjusting the addition of NPA and the crystallization time. Interestingly, the cracked C60 microstructures show superior photoluminescence properties relative to the smooth microstructures due to the increased specific surface area. In addition, C60 microstructures with wide cracks show preferential recognition of silica particles over C60 particles owing to electrostatic interactions between the negatively charged C60 microstructures and the positively charged silica microparticles. These C60 crystals with surface cracks have potential applications from optoelectronics to biology. 相似文献
105.
Bin Su Yang Wang Bo Feng Yongsheng Yan Enwei Zhu Bo Wang Guangbo Che 《Chinese Journal of Physics (Taipei)》2017,55(2):350-354
Organic ultraviolet photodetectors (OUV-PDs) were fabricated utilizing 2-TNATA as an electron donor with Bphen and TPBi as electron acceptors. A high sensitivity of OUV-PDs to UV light was obtained in the range of 300–420 nm. The optimized OUV-PDs composed of Bphen as the acceptor offered a photocurrent density up to 336 µA/cm2 at ?8 V with 365 nm UV light at a power of 1.2 mW/cm2. The high response is attributed to the excellent electron transport ability of Bphen and the matched energy level between 2-TNATA and Bphen. 相似文献
106.
107.
108.
A picosecond widely tunable deep-ultraviolet laser for angle-resolved photoemission spectroscopy
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We develop a picosecond widely tunable laser in a deep-ultraviolet region from 175 nm to 210 nm,generated by two stages of frequency doubling of a 80-MHz mode-locked picosecond Ti:sapphire laser.A β-BaB2O4 walk-off compensation configuration and a KBe2BO3F2 prism-coupled device are adopted for the generation of second harmonic and fourth harmonics,respectively.The highest power is 3.72 mW at 193 nm,and the fluctuation at 2.85 mW in 130 min is less than ±2%. 相似文献
109.
Nanometric gallium-nitride rods were grown on a silicon (1 1 1) substrate through a chemical vapor deposition process with gold particles as the catalyst. Randomly distributed gallium-nitride rods of 20–200 nm in diameter and of various densities and lengths were formed under different deposition conditions. Characterization analyses, such as scanning electron microscopy and optical reflection spectroscopy, have been carried out on samples containing gallium-nitride rods different in size, shape, length and density. While the scanning electron microscopy shows directly the images of the sample surfaces, the optical spectroscopy provides a nondestructive evaluation of the sample surfaces, especially helpful for checking the uniformity of the samples. 相似文献
110.
Chitosan/Ce(IV) redox polymerization‐based amplification for detection of DNA point mutation
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Yanjun Cui Tianwei Tan Jing Yang 《Journal of polymer science. Part A, Polymer chemistry》2016,54(13):1929-1937
Polymerization‐based signal amplification, a technique developed for use in rapid diagnostic tests, hinges on the ability to localize initiators as a function of interfacial binding events. We report here a new DNA detection method in which polymer growth in redox‐polymerization is used as a means to amplify detection signals. The introduction of biotin‐labeled chitosan (biotin‐CS) with highly dense amino groups into the polymerization amplification as macromolecular reducing agent, beneficially simplifies amplification operation, as well as, provides a large amount of initiation points to improve the sensitivity of detection. DNA hybridization, SA and biotin binding reactions led to the attachment of CS on a solid surface where specific DNA sequences were located. With the addition of the mixture containing monomer AM, crosslinker PEGDA and oxidant CAN onto the CS location, the growth of polymer films was triggered to render the corresponding spots readily distinguishable to the naked eye. Direct visualization of 0.21 fmol target DNA molecules of interest was demonstrated. Non‐small cell lung cancer p53 sequence was further selected as a proof‐of‐principle to detect DNA point mutation. The proposed method exhibited an efficient amplification performance for molecule detection, and paved a new way for visual diagnosis of biomolecules. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1929–1937 相似文献