期刊：
Results in Physics,2021年22:103893 ISSN：2211-3797
通讯作者：
Shiliang Wang
作者机构：
[Gao, Yangyang; Zhen, Xing; Hou, Lizhen] Hunan Normal Univ, Sch Phys & Elect, Changsha 410081, Peoples R China.;[Wang, Shiliang; Kuang, Daitao; Deng, Lianwen; Luo, Heng; Liu, Linlin] Cent South Univ, Sch Phys & Elect, Changsha 410083, Peoples R China.;[Chen, Chuansheng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.
通讯机构：
[Shiliang Wang] S;School of Physics and Electronics, Central South University, Changsha 410083, China
关键词：
Core-shell nanoparticles;Metal organic chemical vapor deposition;Thermal stability;Magnetic property;Magnetic alloy
摘要：
Magnetic alloy-C core-shell nanoparticles with tunable elemental components are highly expected for their controllable magnetic, catalytic, and electromagnetic properties, and high air stability. Here we present a simple one-step metal organic chemical vapor deposition for the synthesis of CoNi-C core-shell nanoparticles with tunable Co/Ni molar ratio. The as-synthesized nanoparticles have core sizes of 5-50 nm, shell thicknesses of similar to 5 nm, and tunable Co/Ni molar ratio determined by the molar ratio of Co(acac)(3)/Ni(acac)(2) used in the precursor. The core-shell nanoparticles are very stable in ambient atmosphere at the temperature below 200 degrees C, and exhibit a slight oxidation in the temperature range of 200-400 degrees C. The core-shell nanoparticles with Co/Ni molar ratios of 1.27:1, 0.64:1, and 0.30:1 exhibit saturation magnetization values of 41, 31, and 24 emu/g, and coercivity values of 483, 346, and 362 Oe, respectively. It is demonstrated that the microwave absorption parameters of the as-synthesized nanoparticles can be tuned by the Co/Ni molar ratio, which provides a practical strategy to regulate the microwave absorption properties of nanostructured absorbers.
期刊：
Journal of Alloys and Compounds,2020年826:154084 ISSN：0925-8388
通讯作者：
Chen, Chuansheng
作者机构：
[Fang, Qun; Chen, Chuansheng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Hunan, Peoples R China.;[Chen, Xi'an; Yang, Zhi] Wenzhou Univ, Coll Chem & Mat Engn, Zhejiang Key Lab Carbon Mat, Wenzhou 325027, Peoples R China.;[Chen, Xiaohua; Liu, Tiangui] Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Peoples R China.
通讯机构：
[Chen, Chuansheng] C;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Hunan, Peoples R China.
关键词：
Calcination;Electrochemical electrodes;Manganese compounds;Microspheres;Morphology;Scanning electron microscopy;Supercapacitor;X ray photoelectron spectroscopy;Annealed temperature;Calcination temperature;Electrochemical performance;Large specific surface areas;Pomegranate-type;Porous microspheres;Specific capacitance;ZnMn2O4;Zinc compounds
摘要：
A pomegranate-like ZnMn2O4 sphere electrode material was prepared via co-precipitation and calcination method, and was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and electrochemical workstation. Experimental results display that the calcination temperature has a large influence on the morphology of ZnMn2O4 porous microsphere. When the annealed temperature is 600 degrees C, ZnMn2O4 porous microsphere possesses the best electrochemical performance, in which the specific capacitance reaches 447 F/g at a current density of 1 A/g. The excellent electrochemical performances are mainly attributed to the porous structure and large specific surface area, indicated that the pomegranate-like ZnMn2O4 porous microsphere has a potential application in electrode material of supercapacitor. (C) 2020 Elsevier B.V. All rights reserved.
摘要：
It is essential for multifunctional asphalt to develop the new nanostructures with high photocatalytic activity in order to endow asphalt with the self-cleaning ability of contamination. Multi-walled carbon nanotubes/ZnO (MWNTs/ZnO) composites were synthesized based on microwave irradiation and their structure and photocatalytic properties were investigated. The experimental results showed that MWNTs/ZnO powder with different morphologies was attained such as cone-shaped, floral-patterned and fusiform structures. The as-obtained MWNTs/ZnO composites were proved to possess quite high catalytic activities for degradation of methyl orange (MO). Especially, the floral-patterned MWNTs/ZnO composites displayed better photocatalytic performance than the other composites indicating that the resultant MVVNTs/ZnO composites can be used as photocatalysts without any additional treatment.
摘要：
Despite that a variety of carbon materials have been explored for electrochemical energy storage, rationally design the carbon structure for efficient electrons transfer and ions diffusion to further improve its performance is still a challenge. In this report, a novel three-dimension hybrid carbon material (NCNF/RGO) prepared from reduced graphene oxide (RGO) and N-doped carbon nanoflower (NCNF) consisting of carbon nanosheets has been fabricated by a hydrothermal treatment and freeze-drying method, and demonstrated as supercapacitor's electrode. Benefiting from such structure design with thin porous nanosheets, interworking mesoporous channel and RGO wrapping for efficient electrolyte ions diffusion and electrons transfer, the resulting hybrid electrode displays high specific capacitance of 344 F g(-1) at a current density of 0.5 A g(-1) and 179 F g(-1) even at 50 A g(-1) in the KOH electrolyte, and 152 F g(-1) at 1 A g(-1) in the ionic liquid electrolyte with a wide voltage range. Significantly, the assembled symmetric supercapacitor using the NCNF/RGO as electrode materials reaches a large energy density of 84.2Wh Kg(-1) at a power density of 1.0 kWkg(-1), indicating its great potential application. (c) 2019 Elsevier Ltd. All rights reserved.
摘要：
<jats:p> In order to consider the performance enhancement and feasibility of practical application, this research work discussed the effects of different ions on the photocatalytic activity of TiO<jats:sub>2</jats:sub>/Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> hybrids in detail, involving H[Formula: see text], OH<jats:sup>−</jats:sup>, NH[Formula: see text], and NO[Formula: see text]. The TiO<jats:sub>2</jats:sub>/Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> hybrids were prepared by organic electrolyte-assisted sol–gel method under UV irradiation, and their function mechanisms were analyzed. Experiment results show that the resultant TiO<jats:sub>2</jats:sub>/Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> hybrids possess excellent photocatalytic activity and photocatalytic stability for degradation of organics under acid condition (pH 2–8). Notably, the NO[Formula: see text] ions could accelerate degradation of rhodamine B and methyl orange, and the recyclability of TiO<jats:sub>2</jats:sub>/Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> hybrids can be greatly enhanced in the co-existence of NO[Formula: see text] and NH[Formula: see text]. Meanwhile, this symbiosis of NO[Formula: see text] and NH[Formula: see text] is proven able to buffer the solution pH in photocatalysis. Furthermore, the prominent photocatalytic activity of TiO<jats:sub>2</jats:sub>/Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> hybrids for organic pollutants was mainly attributed to the formation of hydroxyl radicals (OH). The synthetic products show great potential applications in purification of air or wastewater that contains ammonia-nitrogen molecules. </jats:p>
摘要：
A flower-like hierarchical graphene oxide/ZnO (GO/ZnO) macrospheres were fabricated via a low-temperature hydrothemal method, and their photocatalytic performance was tested under natural sunlight and darkness. The resultant GO/ZnO sample displays unique hierarchical macrosphere with diameters in the range of 2–3 μm. The photocatalytic activity of the GO/ZnO microspheres depended on GO, and GO/ZnO macrosphere containing 0.37% GO exhibited very high photocatalytic activity under natural sunlight irradiation and without stirring. Furthermore, GO/ZnO macrospheres possessed good photocatalytic activity under darkness, in which its removal rate of RhB is approximately 5.5 times as many as pure ZnO macrospheres. The enhancement in photocatalytic activity originates from the superior electrical properties of GO, facilitating to transfer the photogenerated electrons and decrease the recombination of photogenerated charge carriers.
摘要：
To improve the photocatalytic activity and endow graphene oxide/TiO2 (GO/TiO2) hybrid with the optical storage ability, WO3 quantum dots (WO3 QDs) were used to modify GO/TiO2 hybrids by sol-gel method, and then the resultant WO3 QDs-GO/TiO2 hybrids were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Experimental results show that WO3 QDs can significantly ameliorate the photocatalytic performance of GO/TiO2 hybrids under visible light, which the reaction rate of WO3 QDs-GO/TiO2 hybrids is about 17 times as much as that of GO/TiO2 hybrids. What's more, WO3 QDs-GO/TiO2 hybrids possess optical memory performance.
摘要：
To improve the photocatalytic activity and electrochemical performance, WO3 quantum dots (WO3 QDs) were used to modify GO/TiO2 (GOT) composites by sol-gel method, and the resultant GO/WO3/TiO2 (GOWT) composites were characterized. Experimental results show that WO3 QDs can enhance photocatalytic activity of GOT composite under visible light, in which its degraded efficiency for Rhodamine B (RhB) is about three times as that of GOT composite. Furthermore, GOWT composite possess excellent electrochemical performance. The enhanced photocatalytic activity is attributed to the special band gap structure and excellent electrochemical properties of WO3 QDs.
摘要：
A versatile approach was developed to synthesize graphene oxide/Bi2O3 nanohybrids by organic electrolyte-assisted coprecipitation method. The structure, morphology and photocatalytic property of GO/Bi2O3 hybrids were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and UV-vis spectrophotometer, respectively. Experimental results showed that the tadpole-like MoO2-Bi2O3 hybrids and WO3-Bi2O3 nanorods were covered on the graphene sheets, respectively. Furthermore, the resultant GO/Bi2O3 hybrids possessed strong adsorption ability and high photocatalytic activity for Rhodamine B (RhB).
