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Your search keyword '"Zhang, Fayun"' showing total 116 results
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116 results on '"Zhang, Fayun"'

22. Preparation of CdS Nanoparticles-TiO2 Nanorod Hererojunction and Their High-Performance Photocatalytic Activity

Author

Zeng Dedong, Jinbing Zhang, Yu Xie, Fahui Wang, Zhang Fayun, Lei Wang, Shenli Rao, Jinsheng Zhao, and Jianhua Song

Subjects
Materials science, Band gap, CdS nanoparticles, Composite number, Nanoparticle, 02 engineering and technology, 010402 general chemistry, lcsh:Chemical technology, 01 natural sciences, Catalysis, lcsh:Chemistry, chemistry.chemical_compound, Specific surface area, Methyl orange, lcsh:TP1-1185, Physical and Theoretical Chemistry, TiO2 nanorods, Heterojunction, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chemical engineering, chemistry, lcsh:QD1-999, hydrothermal method, methyl orange, Photocatalysis, Nanorod, 0210 nano-technology, photocatalysis
Abstract

As a new and emerging technology, photocatalytic oxidation is widely used in the fields of sewage treatment and organic pollution control. In this study, CdS nanoparticles were prepared at room temperature by an innovative preparation method, then TiO2 nanorod&ndash, CdS nanoparticle heterojunction photocatalysts were prepared using the solvothermal method, with TiCl3 used as the precursor for TiO2 nanorods. This study mainly took advantage of the small size of the CdS nanoparticles in combination with TiO2 nanorods, and the resultant heterojunctions had large specific surface areas, thereby increasing the contact area between the catalysts and the contaminants. In addition, due to the lower band gap energy (2.4 eV) of CdS, the photo response range of the heterojunction photocatalysts was also increased. In an experimental study, through photocatalytic performance tests of the catalysts with different weight ratios, it was found that the TiO2(40%)@CdS composite had the best photocatalytic performance and the highest catalytic rate. BET, SEM, and other tests showed that the specific surface area of the TiO2(40%)@CdS composite was the largest. TiO2 nanorods and CdS particles were uniformly distributed in the composite, and the optical response range was extended to the visible light region.

Published
2020

27. Conformation and electronic structure of DNA in carbon nanotubes: a molecular dynamics and first‐principles study

Author

Zha Goujun and Zhang Fayun

Subjects
Conformational change, Chemistry, Molecular biophysics, Biomedical Engineering, Stacking, Bioengineering, 02 engineering and technology, Electronic structure, Carbon nanotube, 010402 general chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, 0104 chemical sciences, law.invention, Molecular dynamics, Crystallography, Ab initio quantum chemistry methods, law, General Materials Science, sense organs, 0210 nano-technology, Alpha helix
Abstract

The conformation and electronic structure of DNA in single-walled carbon nanotubes (SWCNT) were studied by combining molecular dynamics and first-principles methods. It was found that the π orbital of the SWCNT inner wall induces a conformational change in single stranded DNA (ssDNA) and promotes the adsorption of general-sequence oligonucleotides on the inner walls of the SWCNTs due to π–π stacking interactions. Moreover, they found that the adsorbed oligonucleotides form a helix because of electrostatic and torsional interactions within the sugar–phosphate backbone.

Published
2017
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28. Analysis of the Effect of a Vertical Magnetic Field on Melt Convection and Oxygen Transport During Directional Solidification of Multi-Crystalline Silicon by Numerical Simulation

Author

Senlin Rao, Luo Yufeng, Botao Song, Zhang Fayun, and Hu Yun

Subjects
Convection, Materials science, Silicon, General Chemical Engineering, chemistry.chemical_element, directional solidification, multi-crystalline silicon, 02 engineering and technology, engineering.material, 01 natural sciences, Inorganic Chemistry, melt convection, oxygen impurity, Condensed Matter::Superconductivity, 0103 physical sciences, lcsh:QD901-999, General Materials Science, Crystalline silicon, Directional solidification, 010302 applied physics, Oxygen transport, Mechanics, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Magnetostatics, Polycrystalline silicon, chemistry, numerical simulation, engineering, Limiting oxygen concentration, lcsh:Crystallography, 0210 nano-technology
Abstract

Melt convection during the directional solidification process of multi-crystalline silicon plays a critical role in the transport of impurities. The utilization of a static magnetic field is an effective way to control the melt convection pattern. Studying the effect of the Lorentz force induced by the vertical magnetic field (VMF) on the melt convection of silicon in detail is beneficial to optimize the magnetic field parameters in the production process. Based on the numerical simulation method of multi-physics coupling, this paper explores the effects of different VMF intensities on the convection of silicon melt and the transport of oxygen in the melt during the directional solidification of polycrystalline silicon. The results show that in the first 125 minutes of the crystallization stage, the melt convection velocity is affected significantly by the magnetic field intensities. When different convection circulations are present in the silicon melt, the upper circulation easily transports oxygen to the furnace atmosphere, and the subjacent circulation easily lead to the retention and accumulation of oxygen. Enhancing the VMF intensity to a certain extent can reduce the size of the oxygen retention region in the silicon melt, and the time of the first disappearance of the subjacent circulation near the sidewall of the crucible is shortened. Then the average oxygen concentration in the silicon melt can be reduced. However, a larger vertical magnetic field intensity can result in greater average oxygen concentration in the oxygen retention region.

Published
2019
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36. Fabrication of Cu2O/Si nanowires photocathode and its photoelectrochemical properties.

Author

Hu, Yun, Luo, Yufeng, Liu, Shaohuan, Zhang, Fayun, Rao, Senlin, Wang, Fahui, Li, Yunming, Li, Shuigen, and Zhong, Wei

Subjects
PHOTOCATHODES, SILICON nanowires, NANOPARTICLES, SILICON surfaces, REFLECTANCE, WAVELENGTHS
Abstract

Using a simple dipping method, Cu2O nanoparticles were successfully deposited on the surface and the sidewall of silicon nanowires (Si NWs). As a photocathode, the Cu2O/Si NWs composites not only show a low reflectance of 10.75% in the 300–900 nm wavelength range, but also can enhance the separation of the photogenerated electron–hole pairs due to the junction formed by Cu2O and Si NWs. The Cu2O/Si NWs-20 min photocathode achieved a photocurrent of 3.5 mA cm−2 at −0.8 V versus AgCl/Ag and a photoconversion efficiency of 1.2%. [ABSTRACT FROM AUTHOR]

Published
2020
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41. An aqueous solution method towards Sb2S3 thin films for photoanodes.

Author

Zhong, Panping, Xie, Juan, Bagheri, Robabeh, Yi, Qinghua, Chen, Qi, Tan, Jingrou, He, Liang, Zhang, Fayun, Zhang, Labao, and Zou, Guifu

Subjects
PHOTOELECTROCHEMICAL cells, THIN films, ATOMIC layer deposition, CHEMICAL vapor deposition, AQUEOUS solutions
Abstract

An aqueous solution approach, integrating atomic layer deposition and chemical vapor deposition, is proposed to grow a high-quality Sb2S3 thin film. The Sb2S3 thin film is uniform and dense with a bandgap of 1.78 eV. The photocurrent density of the Sb2S3 sensitized TiO2 array electrode is 40 μA cm−2, which is nearly 25 and 93 times than that of TiO2 and Sb2S3 photoanodes, respectively. [ABSTRACT FROM AUTHOR]

Published
2019
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43. Hierarchical NiCo hydroxide nanosheets deposited on 3D porous Ni arrays for cost-effective high-performance supercapacitors.

Author

Li, Yunming, Chen, Jiahui, Ye, Huangqing, Zhang, Fayun, Fu, Xian-Zhu, Sun, Rong, and Wong, Ching-Ping

Subjects
SUPERCAPACITORS, GRAPHENE, HYDROXIDES, ELECTROCHEMICAL analysis, ELECTRODES
Abstract

The development of flexible three-dimensional (3D) nanostructured electrodes has been regarded as a promising strategy to fulfill high-performance supercapacitors. Herein, we report a cost-effective method for fabricating flexible supercapacitor electrodes consisting of NiCo-LDH nanosheets electrodeposited on 3D porous Ni arrays/conductive cloth (NiCo-LDH@3D Ni/CC). The hierarchical 3D porous Ni arrays with high conductivity and large specific area not only provide effective interconnected conductive networks, but also enable a high mass loading of active materials. The resultant NiCo-LDH@3D Ni/CC electrode exhibits a high mass capacitance of 2248 F g−1 and a high areal capacitance of 3260 mF cm−2 at 5 mA cm−2. Ultimately, the symmetric solid-state supercapacitor assembled with NiCo-LDH@3D Ni/CC displays a high areal capacitance of 116.7 mF cm−2 at 5 mA cm−2, and excellent cycling stability (full capacitance retention after 10,000 cycles at 10 mA cm−2). This work demonstrates a facile and low-cost strategy for flexible energy storage applications. [ABSTRACT FROM AUTHOR]

Published
2019
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46. Is Intracranial Pressure Monitoring of Patients With Diffuse Traumatic Brain Injury Valuable? An Observational Multicenter Study

Author

Yuan, Qiang, primary, Wu, Xing, additional, Cheng, Hongwei, additional, Yang, Chaohua, additional, Wang, Yuhai, additional, Wang, Ersong, additional, Qiu, Binghui, additional, Fei, Zhimin, additional, Lan, Qing, additional, Wu, Sirong, additional, Jiang, Yunzhao, additional, Feng, Hua, additional, Liu, Jingfang, additional, Liu, Ke, additional, Zhang, Fayun, additional, Jiang, Rongcai, additional, Zhang, Jianmin, additional, Tu, Yue, additional, Wu, Xuehai, additional, Zhou, Liangfu, additional, and Hu, Jin, additional

Published
2016
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47. Large-Grained Cu2BaSnS4Films for Photocathodes

Author

Xie, Juan, Yi, Qinghua, Zhang, Fayun, Bagheri, Robabeh, Zheng, Fengang, and Zou, Guifu

Abstract

p-Type compounds Cu2BaSnS4(CBTS) are extremely attractive materials for photocathode applications because of their suitable conduction and valence bands, earth-abundant sources, and environmental friendly nature. Herein, an inexpensive and reproducible aqueous solution approach has been developed to synthesize CBTS films with single-crystalline grains as large as micron scale. Because of the large crystalline grains, the as-grown CBTS films show excellent carrier mobility (1.29 cm2/V·s). Greater than 4 mA·cm–2photocurrent density has been obtained in a neutral solution for bare Mo/CBTS film photocathodes under 100 mW·cm–2illumination at 0 V versus reversible hydrogen electrode.

Published
2024
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50. Gd2O3nanoparticles modified g-C3N4with enhanced photocatalysis activity for degradation of organic pollutants

Author

Zhou, Yipeng, Zeng, Fanshan, Sun, Chaoyang, Wu, Jun, Xie, Yu, Zhang, Fayun, Rao, Senlin, Wang, Fahui, Zhang, Jinbing, Zhao, Jinsheng, and Li, Shiqian

Abstract

Gd2O3nanoparticles modified g-C3N4photocatalytic composites were synthesized by a simple one-step hydrothermal method. The structure, morphology, optical properties of the prepared photocatalyst were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), field emission transmission electron microscopy (FETEM) and X-ray photoelectron spectroscopy (XPS). The result demonstrates that gadolinium is mainly dispersed on the surface of g-C3N4in the form of Gd2O3, and does not destroy the lattice structure of g-C3N4. Besides, the gadolinium can cause the red shift of the absorption edge of light, narrow the band gap, and increase the separation efficiency of the photogenerated electron and hole of g-C3N4. Especially, the specific surface area of g-C3N4can be significantly increased. Furthermore, g-C3N4/Gd-0.05 displays the highest photodegradation performance when it is used for degradation of methyl orange (MO), methylene blue (MB) and Rhodamine B (RhB). The photodegradation rate of g-C3N4/Gd-0.05 composites is 72.4% for MO, 95.5% for RhB, 100% for MB after 120 min under visible light (λ > 420 nm) irradiation. Narrow band gap promotes the separation of photogenerated electron and hole, which enhances the photocatalytic activity of g-C3N4. It is noted that g-C3N4/Gd-0.05 exhibits excellent photocatalytic stability by the photocurrent and the cyclic photodegradation of MO.

Published
2021
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