The research on aggregation-induced emission (AIE) has drawn increasing interests in the past decade. With the efforts scientists paid, a variety of AIE systems have been developed, among which the tetraphenylethelene...
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The research on aggregation-induced emission (AIE) has drawn increasing interests in the past decade. With the efforts scientists paid, a variety of AIE systems have been developed, among which the tetraphenylethelene and silole derivatives are the most studied. Development of new AIE systems could further enrich the AIE molecules and promote the development of AIE area. In this communication, we prepared a new AIE system based on 1,2,4,6-tetraphenylpyridinium ions according to the restriction of intramolecular rotation mechanism. These molecules could be facilely synthesized via one-step and one-pot reaction. The ionic AIE-active molecules could find wide application in sensing and optoelectronic areas.
Mesoporous vOx@carbon composites were synthesized via ultrasound-assistant impregnation method with mesoporous carbon C-FDU15 as the host. the composites with 32.26 wt% V2O5 loading yield the best capacitance (128 F/g...
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Ca(Zn1/3Nb2/3)O3/CaTiO3 multilayer heterogeneous thin films have been prepared by sol-gel method. The films are confirmed to be perovskite phase with dense, uniform surface, which possess higher dielectric constant, e...
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To investigate the quantitative relationship between the electromagnetic-shielding property of composites and the distribution of inclusions, a scheme for predicting the shielding effectiveness of composites containin...
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To investigate the quantitative relationship between the electromagnetic-shielding property of composites and the distribution of inclusions, a scheme for predicting the shielding effectiveness of composites containing variously-distributed flaky inclusions is proposed. The scheme is based on equivalent parameters of homogeneous comparison materials and the plane-wave shielding theory. It leads to expli- cit formulas for the shielding effectiveness of multi-layered composites in terms of microstructural parameters that characterize the shape, distribution and orientation of the inclusions. For single layer composite that contains random and aligned flaky silver-coated carbonyl-iron particles with fractions of different volume, the predicted shielding effectiveness agrees well with the experimental data. As for composites containing aligned flaky particles,the shielding effectiveness obtained by the proposed scheme and experiment data is higher than that the random case, e.g. about 20 dB higher at 750 MHz. The proposed scheme is a straightforward method for optimizing future composite de- signs.
Raw ginger was introduced to a series of composite antioxidants. The specimens performed better efficiency than ordinary antioxidants while extracting vitamin C from strawberry. The results suggested that, by employin...
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Raw ginger was introduced to a series of composite antioxidants. The specimens performed better efficiency than ordinary antioxidants while extracting vitamin C from strawberry. The results suggested that, by employing raw ginger composite antioxidant, the reservation of vitamin C could be 91.63% in washing process and 76.68% in squeezing process respectively. Furthermore, in squeezing process, the reservation of vitamin C reached 84.78% while the concentrate of raw ginger antioxidant was 0.03%. The both deposits performed perfect synergy effectively. Raw ginger composite antioxidant could be the well agent to extract vitamin C from fruit.
As a layered-structure semiconductor material with wide band gap, MoO 3 has been considered to be a promising candidate for application in gas sensor. Recently, gas sensor based on MoO 3 have been found to have a resp...
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As a layered-structure semiconductor material with wide band gap, MoO 3 has been considered to be a promising candidate for application in gas sensor. Recently, gas sensor based on MoO 3 have been found to have a response towards various gases such as H 2 S, NO 2 , NH 3 , trimethylamine, formaldehyde and H 2 in the temperature range of 300–600 °C. Although MoO 3 films and nanorods are not sensitive to ethanol gas, it is found that the ultralong MoO 3 nanobelts have a good sensitivity and selectivity to ethanol gas in our works. In the present work, the ultralong MoO 3 nanobelts are prepared by hydrothermal method using a molybdenum organic salt precursor. The nanobelts are flexible with an average length of 200-300μm and width of 500nm, which won’t be broken even after bended or distorted. The nanobelts are characterized by using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Raman spectra. Gas sensor based on ultralong and flexibility MoO 3 nanobelts is then fabricated. The sensor shows a good sensitivity towards ethanol gas, while almost no response towards other reducing gases, such as ammonia and formaldehyde in the temperature range of 220–380 ℃, the detection limit to ethanol gas may reach to 5ppm at the temperature of 380℃, which indicates that this kind of sensor has a promising future for ethanol detection. In conclusion, a gas sensor has been fabricated based on ultralong and flexibility MoO 3 nanobelts, which are prepared by hydrothermal method using a molybdenum organic salt precursor, and it is sensitive to ethanol gas. The reason for the good sensitivity to ethanol may be due to the large specific surface area, axial electron transfer and the non-stoichiometry of MoO 3 nanobelts.
Single-nanowire solar cells have been considered to be the promising candidates as the nanoelectronical and flexibledevices, as they possess large surface-to-volume ratio and short minority carrier’stransferring path...
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Single-nanowire solar cells have been considered to be the promising candidates as the nanoelectronical and flexibledevices, as they possess large surface-to-volume ratio and short minority carrier’stransferring path. Recently, there is some kinds of heterostructures are used to fabricated single-nanowire solar cells, such as CdS/Cu 2 S, CuInSe 2 /CdS. Among them, cadmium sulfide (CdS) and silver sulfide (Ag 2 S) have been attracted much attention for excellentoptoelectronic property, and surface-passivated is an important process to improve the efficiency. Till now, there is few works focused on the influence of the surface-passivated layer on the photovoltaicefficiency of the CdS/Ag 2 S core-shell single-nanowires solar cells. Herein, CdS nanowires were synthesized via vapor liquid solid(VLS) method, which is used as the core structure. To obtain CdS/Ag 2 S core-shell structure, cation exchange was carried out through mixing CdS solution with AgNO 3 solution.A ZnS passivation layer with the thickness of 0nm was achieved by chemical bath deposition (CBD) process. The single CdS/Ag 2 S core-shell nanowires were separated individually on the regular Au pattern fabricated by the photolithography technique, and then two ends of the nanowires were well contacted with Au electrodes by using the electron beam lithography. X-raydiffraction, SEM, X-ray spectroscopy and TEM techniques were used to character the microstructure, morphology and combining chemical state. The fabricated single-nanowire solar cells were irradiated under AM 1.5G illumination, an efficiency improvement from 1.8% to 2.4%was achieved due to the preventing charge carriers from reaching the surface by surface-passivated layer. In conclusion, CdS/Ag 2 Sheterostructures had been successfully prepared by cation exchange method, achieving an efficiency enhancement by forming the surface-passivated single-nanowire solar cells.
Quantum dots sensitized solar cells (QDSSCs) have been attracted much attention as the next generation photovoltaic devices, due to the size-effect, high absorption coefficient and multiple excitation generation of qu...
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Quantum dots sensitized solar cells (QDSSCs) have been attracted much attention as the next generation photovoltaic devices, due to the size-effect, high absorption coefficient and multiple excitation generation of quantum dots (QDs). Recently, Mn-CdS/CdSe and CuInS 2 /Mn-CdS sensitized solar cells has been obtained. However, the performance of the solar cells is still limited by the transfer barrier of the photo-induced electrons from nanoparticles. Nowadays, the single crystalline nanorods, nanowires and nanotubes arrays structure have been widely prepared to improve the electron transfer. In order to effectively enhance the efficiency, the nanowire structure is expected to be employed in both photo-anodes and counter electrodes for QDSSCs fabrication. In this work, Cu 2 S nanowire arrays are prepared by the solution method, which are employed to the photo-cathodes of solar cells, meanwhile, single crystalline anatase TiO 2 nanowires arrays are prepared by hydrothermal method and then be transferred to FTO substrate as the photo-anodes. CuInS 2 and Mn-CdS QDs are deposited on TiO 2 nanowire arrays films by using linking assembly method and chemical bath deposition. The structure, morphology and optical properties have been characterized by XRD, SEM, UV-Vis spectra. Under a solar illumination, the photovoltaic efficiency of this double-side nanowire structure based solar cells are obviously enhanced from 3.3% to 4.1%. In summary, the CuInS 2 /Mn-CdS QDs sensitized solar cells by using TiO 2 and Cu 2 S nanowire arrays as the photo-anodes and photo-cathodes have been fabricated. It is found that the photovoltaic performance of these QDSSCs is obviously enhanced comparing to the nanoparticles based solar cells. The reason is originated from that fact that the better electron transfer and injection from the one-dimensional nanowire arrays structure.
Indoor air quality has received immense ***,a carcinogenicity material,is a typical gaseous indoor *** oxidation has been studied extensively to purify the polluted air and to remove *** has been the most popular phot...
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Indoor air quality has received immense ***,a carcinogenicity material,is a typical gaseous indoor *** oxidation has been studied extensively to purify the polluted air and to remove *** has been the most popular photocatalyst for environmental purification due to its good chemical stability,high oxidized activity, nontoxicity and low ***,its quantum efficiency in photocatalyst reaction is generally not high enough from application point of *** this work,novel TiO nanotube arrays modified with
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