scholarly journals Nanosheet-Assembled ZnO Microflower Photocatalysts

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Siwen Zhang ◽  
Bosi Yin ◽  
Yang Jiao ◽  
Yang Liu ◽  
Fengyu Qu ◽  
...  

Large scale ZnO microflowers assembled by numerous nanosheets are synthesized through a facile and effective hydrothermal route. The structure and morphology of the resultant products are characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Photocatalytic properties of the as-synthesized products are also investigated. The results demonstrate that eosin red aqueous solution can be degraded over 97% after 110 min under UV light irradiation. In addition, methyl orange (MO) and Congo red (CR) aqueous solution degradation experiments also are conducted in the same condition, respectively. It showed that nanosheet-assembled ZnO microflowers represent high photocatalytic activities with a degradation efficiency of 91% for CR with 90 min of irradiation and 90% for MO with 60 min of irradiation. The reported ZnO products may be promising candidates as the photocatalysts in waste water treatment.

2017 ◽  
Vol 17 ◽  
pp. 166-170 ◽  
Author(s):  
M. Ahila ◽  
D. Pathinettam Padiyan

Bi2O3 nanostructures were synthesized through a simple electrolysis based oxidation using NaOH electrolyte and annealed at 300 °C, 400 °C, 500 °C and 600 °C. The obtained Bi2O3 nanostructures were characterized using X-ray diffraction and photoluminescence spectroscopy (PL). Bi2O3 crystal structure was confirmed by XRD. When free electron and holes are combined together then emission signals are emitted from PL spectra. With this process, it is studied about the recombination and separation of photo generated holes and electrons. The photocatalytic activities of Bi2O3 films were evaluated for the degradation of Congo red in aqueous solution under UV light irradiation. Among the four samples, Bi2O3 films annealed at 300 °C have better efficiency in removing the congo red dye. For Bi-3, the initial concentration of 10 ppm decreases to 1.11 ppm after 420 min.


2020 ◽  
Vol 75 (8) ◽  
pp. 727-732
Author(s):  
Chen Zhang ◽  
Jian-Qing Tao

AbstractA new Cu(II) metal-organic framework, [Cu(L)(OBA)·H2O]n (1) [H2OBA = 4,4′-oxybis(benzoic acid), L = 3,5-di(1H-benzimidazol-1-yl)pyridine] was hydrothermally synthesized and characterized through IR spectroscopy, elemental and thermal analysis and single-crystal X-ray diffraction. Complex 1 is a four-connected uni-nodal 2D net with a (44·62) topology which shows an emission centered at λ ∼393 nm upon excitation at λ = 245 nm. Moreover, complex 1 possesses high photocatalytic activities for the decomposition of Rhodamine B (RhB) under UV light irradiation.


2010 ◽  
Vol 148-149 ◽  
pp. 1204-1207
Author(s):  
Jing Hu ◽  
Ming Guo Ma ◽  
Jian Zhang Li

The Zn/Sn-composite oxide nanogranules were synthesized via a simple hydrothermal method, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that the hydrothermal temperature significantly influences the morphology, microstructure, and composition of the as-prepared samples. And the nano-sized ZnO/Zn2SnO4 exhibited high photocatalytic activities on the degradation of methyl orange (MO) under ultraviolet (UV) light irradiation.


2016 ◽  
Vol 16 (4) ◽  
pp. 4029-4034 ◽  
Author(s):  
Chunxia Liu ◽  
Lixia Yang ◽  
Dan Yue ◽  
Mengnan Wang ◽  
Lin Jin ◽  
...  

Rare earth ions (Tb3+, Eu3+) doped CaWO4 microstructures were synthesized by a facile hydrothermal route without using any templates and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectrum. The results indicate that the asprepared samples are well crystallized with scheelite structure of CaWO4, and the average diameter of the microstructures is 2∼4 μm. The morphology of CaWO4:Eu3+ microstructures can be controllably changed from microspheres to microflowers through altering the doping concentration of Eu3+ from 3% to 35%, and the microflowers are constructed by a number of CaWO4:Eu3+ nanoflakes. Under the excitation of UV light, the emission spectrum of CaWO4:Eu3+ is composed of the characteristics emission of Eu3+ 5D0-7FJ (J = 1, 2, 3, 4) transitions, and that of CaWO4:Tb3+ is composed of Tb3+ 5D4-7FJ (J = 6, 5, 4, 3) transitions. Both of the optimal doping concentrations of Tb3+ and Eu3+ in CaWO4 microstructures are about 5%.


NANO ◽  
2018 ◽  
Vol 13 (05) ◽  
pp. 1850056 ◽  
Author(s):  
Yugan He ◽  
Qi Yan ◽  
Xiaoyu Chang ◽  
Meiying Zhu ◽  
Weiwei Wang ◽  
...  

A TiO2 photocatalyst with peony-like microstructures and a large percentage of exposed {001} facets was synthesized using a facile solvethermal method. The peony-like TiO2 was obtained using HF as a capping agent, TiCl4 as the precursor and ethanol as the solvothermal agent. The parameters which influence the mophology and formation mechanism of the products including the HF concentration, the reaction time and temperature and the solvothermal solvent, were investigated. The samples were characterized using field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction and N2 adsorption and desorption analysis. As the reaction time or reaction temperature increased, the morphology TiO2 changed from hexagonally assembled microspheres to peony-like microflowers which were composed of stacks of ultrathin nanosheets. The other reaction parameters also play a crucial role in the formation of the TiO2 microstuctures. Photocatalytic experiments showed that the synthesized TiO2 outperformed Degussa P25 in the photodegradation of methelene blue under a very weak UV light irradiation (power: 8[Formula: see text]W, light intensity: 0.4[Formula: see text]mW[Formula: see text]cm[Formula: see text]).


2010 ◽  
Vol 663-665 ◽  
pp. 187-190 ◽  
Author(s):  
Yu Hui Zhang ◽  
Ji Xin Su ◽  
Xiao Peng Wang ◽  
Qi Pan ◽  
Wen Qu

Based on X-ray diffraction results, the gallery height of modified Mg3Al-LDH was expanded to 9.6Å from the original 4.8Å, indicating that the H3PW12O40 was indeed inserted into the hydroxide layers. Moreover, the results of FT-IR spectra proved the Keggin structure of PW11O397- species. The resulting material showed a high activity of degradation of methyl orange in the presence of H2O2 and UV light irradiation.


2020 ◽  
Vol 76 (9) ◽  
pp. 850-855
Author(s):  
Ning-Ning Chen ◽  
Chen Zhang ◽  
Jian-Qing Tao

A novel twofold interpenetrating two-dimensional (2D) ZnII coordination framework, poly[[(μ-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene-κ2 N 3:N 3)(μ-naphthalene-2,6-dicarboxylato-κ2 O 2:O 6)zinc(II)] dimethylformamide monosolvate], {[Zn(C12H6O4)(C14H14N4)]·C3H7NO} n or {[Zn(1,3-BMIB)(NDC)]·DMF} n (I), where H2NDC is naphthalene-2,6-dicarboxylic acid, 1,3-BMIB is 1,3-bis(2-methyl-1H-imidazol-1-yl)benzene and DMF is dimethylformamide, was prepared and characterized through IR spectroscopy, elemental analysis, thermal analysis and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis revealed that (I) exhibits an unusual twofold interpenetrating 2D network. In addition, it displays strong fluorescence emissions and a high photocatalytic activity for the degradation of Rhodamine B (RhB) under UV-light irradiation.


2011 ◽  
Vol 374-377 ◽  
pp. 956-959
Author(s):  
Li Yun Yang ◽  
Gui Peng Feng ◽  
Yong Cai Zhang

ZnO2 nanorods were synthesized via hydrothermal treatment of 2ZnCO3•3Zn(OH)2 powder in 30 mass% H2O2 aqueous solution at 170 °C for 12 h, and characterized by means of X-ray diffraction, transmission electron microscopy and UV–vis diffuse reflectance spectra. Besides, the photocatalytic activity of the as-synthesized ZnO2 nanorods was tested for the degradation of methyl orange in distilled water under UV light irradiation.


2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Mingjie Ma ◽  
Weijie Guo ◽  
Zhengpeng Yang ◽  
Shanxiu Huang ◽  
Guanyu Wang

TiO2/fine char (FC) photocatalyst was prepared via sol-gel method with tetrabutyl titanate as the precursor and FC as the carrier. The structural property of TiO2/FC photocatalyst was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the photocatalytic activity of TiO2/FC was evaluated by photocatalytic degradation of rhodamine B (RhB) aqueous solution under UV light irradiation. The results showed that TiO2was successfully coated on the surface of FC, and the TiO2/FC photocatalyst had better photocatalytic efficiency and stability for degradation of RhB under UV light illumination as compared to that of the pure TiO2and FC. The study provided a novel way for the application of FC to the photocatalytic degradation of organic wastes.


2015 ◽  
Vol 1087 ◽  
pp. 218-222
Author(s):  
Siti Aida Ibrahim ◽  
Srimala Sreekantan

Nanostructured Fe-TiO2 and TiO2 with anatase structure were synthesized via combination method of sol-gel and peptization process. The samples were characterized by X-ray diffraction (XRD), Transmission emission microscopy (TEM) and UV-Vis spectroscopy (UV-Vis). The presence of Fe3+ ion shifted the absorption profile of TiO2 to the longer wavelength side of the spectrum, indicating an obvious photocatalytic activity under visible irradiation. Photocatalytic activity of the samples were evaluated by methyl orange (MO) discolouration under UV-light irradiation. Compared with the pure TiO2 nanoparticles, the Fe-TiO2 nanoparticles exhibited higher photocatalytic activity with 95% discoloration within 2 h.


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