Facile Synthesis and Photocatalytic Performance of W18O49 Nanorods

2017 ◽  
Vol 726 ◽  
pp. 360-364
Author(s):  
Shuo Wang ◽  
Xia Xia Bai ◽  
Hui Zhang

W18O49 nanorods photocatalyst was successfully synthesized by a facile pyrolyzing ammonium metatungstate in a reductive atmosphere of H2 (5 vol %)/Ar. The synthesized W18O49 nanorods were characterized by X-ray diffraction (XRD), Raman spectrum, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and ultraviolet-visible (UV-Vis) absorption spectroscopy. The results show that W18O49 nanorods are about 190 nm in diameter and around 4.8 μm in length, and they possess the band-gap energy of 2.32 eV. Moreover the photocatalytic activity of W18O49 nanorods was evaluated by degrading methylene blue (MB) under visible light irradiation. The result illustrates that the W18O49 nanorods have a photodegradation efficiency of 60% for MB under the irradiation of xenon lamp (250 W, λ > 420 nm) for 2 h.

2019 ◽  
Vol 43 (3-4) ◽  
pp. 135-139
Author(s):  
Pegah Farokhian ◽  
Manouchehr Mamaghani ◽  
Nosrat Ollah Mahmoodi ◽  
Khalil Tabatabaeian ◽  
Abdollah Fallah Shojaie

An efficient protocol for the facile synthesis of a series of pyrido[2,3- d]pyrimidine derivatives has been developed applying Fe3O4–ZnO–NH2–PW12O40 nanocatalyst in water. This novel method has the benefits of operational simplicity, green aspects by avoiding toxic solvents and high to excellent yields of products. Fe3O4–ZnO–NH2–PW12O40 was synthesized and characterized by Fourier transform infrared, X-ray diffraction, vibrating sample magnetometer, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy analyses. The nanocatalyst is readily isolated and recovered from the reaction mixture by an external magnet.


2016 ◽  
Vol 09 (03) ◽  
pp. 1650045 ◽  
Author(s):  
Pei-Ying Li ◽  
Kai-Yu Cheng ◽  
Xiu-Cheng Zheng ◽  
Pu Liu ◽  
Xiu-Juan Xu

Chitosan-ionic liquid conjugation (CILC), which was prepared through the reaction of 1-(4-bromobutyl)-3-methylimidazolium bromide (BBMIB) with chitosan, was firstly used to prepare functionalized graphene composite via the chemical reduction of graphene oxide (GO). The obtained water soluble graphene-based composite was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), ultraviolet-visible (UV–Vis) spectroscopy and so on. CILC-RGO showed excellent dispersion stability in water at the concentration of 2.0 mg/mL, which was stable for several months without any precipitate. This may be ascribed to the electrostatic attraction and [Formula: see text]–[Formula: see text] interaction between CILC and graphene.


2013 ◽  
Vol 4 ◽  
pp. 699-704 ◽  
Author(s):  
Raju Prakash ◽  
Katharina Fanselau ◽  
Shuhua Ren ◽  
Tapan Kumar Mandal ◽  
Christian Kübel ◽  
...  

A carbon-encapsulated Fe3O4 nanocomposite was prepared by a simple one-step pyrolysis of iron pentacarbonyl without using any templates, solvents or surfactants. The structure and morphology of the nanocomposite was investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller analysis and Raman spectroscopy. Fe3O4 nanoparticles are dispersed intimately in a carbon framework. The nanocomposite exhibits well constructed core–shell and nanotube structures, with Fe3O4 cores and graphitic shells/tubes. The as-synthesized material could be used directly as anode in a lithium-ion cell and demonstrated a stable capacity, and good cyclic and rate performances.


2020 ◽  
Vol 9 (1) ◽  
pp. 14
Author(s):  
Yi Wei ◽  
Peiwei Tang ◽  
Minfeng Huang ◽  
Yongzhang Pan

A novel photocatalyst powder, BiOI/BiOBr/MoS2, was synthesized by a simple solvothermal method. X-ray diffraction (XRD), specific surface area and pore size analyses, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray energy spectrometry (EDS) were utilized to characterize the prepared samples. After evaluating the photocatalytic performance of the catalyst, it was loaded on the glass fiber and carbon fiber by polyvinylidene fluoride (PVDF) and N-methylpyrrolidone, respectively. The photocatalytic activity of the composite was investigated by the degradation of ammonia nitrogen wastewater. The fiber cloth solved the problem of separation of powder from solution after reaction, and the presence of the binder reduces the agglomeration of the nanoparticles in the water. After four times repeated experiments, the degradation of simulate ammonia nitrogen wastewater by loaded glass fiber and loaded carbon fiber are 74.1% and 60.58%. Fixation of BiOI/BiOBr/MoS2 powders on fiber cloth solve the problem of difficult recovery of powder photocatalytic materials and it can be recycled, which has economic valuable.


2014 ◽  
Vol 787 ◽  
pp. 52-57
Author(s):  
Feng Chen ◽  
Cheng Bao Liu ◽  
Jun Chao Qian ◽  
Zheng Ying Wu ◽  
Zhi Gang Chen

Biomophic titanium oxide with nanocrystalline was successfully synthesized using napkin template, which everybody uses. Unique biomorphic microstructures were characterized by field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and nitrogen absorption-desorption techniques. TiO2 material was characterized by repetitious networks consisting of the fibers with diameter of 1-6μm. The results showed that the products were composed by polycrystalline TiO2 nanoparticles with diameter of ca. 5-8 nm and the high specific surface area (81.0 m2·g-1) of sample,which were believed to result from the X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and the Brunauer-Emmett-Teller (BET) method. While the concentration of acid black solution was 20 mg/L, catalyst amount 0.1 g/L, the reaction had a higher photocatalytic performance following irradiation with a visible light by xenon lamp, the decoloring rate can reach over 100% after 250 min.


2014 ◽  
Vol 496-500 ◽  
pp. 297-300 ◽  
Author(s):  
Bi Tao Liu ◽  
Liang Liang Tian ◽  
Ling Ling Peng

A series of composites of the high photoactivity of {001} facets exposed BiOCl and grapheme sheets (GS) were synthesized via a one-step hydrothermal reaction. The obtained BiOCl/GS photocatalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy, transmission electron microscopy (TEM), Ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy. The as-prepared BiOCl/GS photocatalyst showed enhanced photocatalytic activity for the degradation of methyl orange (MO) under UV and visible light (λ > 400 nm). The enhanced photocatalytic activity could be attributed to oxygen vacancies of the {001} facets of BiOCl/GS and the high migration efficiency of photo-induced electrons, which could suppress the charge recombination effectively.


2014 ◽  
Vol 879 ◽  
pp. 155-163 ◽  
Author(s):  
Rahizana Mohd Ibrahim ◽  
Markom Masturah ◽  
Huda Abdullah

Nanoparticles of Zn1-xFexS ( x=0.0,0.1,0.2 and 0.3) were prepared by chemical co-precipitation method from homogenous solution of zinc and ferum salt at room temperature with controlled parameter. These nanoparticles were sterically stabilized using Sodium Hexamethaphospate (SHMP). Here, a study of the effect of Fe doping on structure, morphological and optical properties of nanoparticles was undertaken. Elemental analysis, morphological and optical properties have been investigated by Fourier-Transform-Infrared spectroscopy (FT-IR), X-Ray Fluorescence (XRF), Field Emmision Scanning Electron Microscopy (FESEM), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and UV-Visible Spectroscopy. FTIR measurement confirmed the presence of SHMP in the nanoparticles structure with the FESEM images depicting considerable less agglomeration of particles with the presence of SHMP. While XRF results confirm the presence of Fe2+ ion as prepared in the experiment. The particles sizes of the nanoparticles lay in the range of 2-10 nm obtained from the TEM image were in agreement with the XRD results. The absorption edge shifted to lower wavelengths with an increase in Fe concentration shown in the UV-Vis spectroscopy. The band gap energy value was in the range of 4.95 5.15 eV. The blueshift is attributed to the quantum confinement effect.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Sirajul Haq ◽  
Aqsa Waheed Raja ◽  
Sadiq Ur Rehman ◽  
Amine Mezni ◽  
Manel Ben Ali ◽  
...  

The NiO-ZnO nanocomposite (NiO-ZnO NC) was synthesized by ecofriendly process by using Diospyros kaki (D. kaki) extract of leaves as reducing and capping agents. X-ray diffraction (XRD) was used for examined crystallinity, cell dimensions, and crystallite size (7.6 nm). To determine the purity of sample and weight percentage, energy dispersive X-ray (EDX) is used. The surface morphology was determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). By using Fourier transform infrared spectroscopy (FTIR), functional groups in samples were determined. By using diffuse reflectance data (DRS), band gap energy calculated via Tauc plot was 3.23 eV. The photocatalytic activity was checked against brilliant green (BG) and 4-nitrophenol (4-NP) and 92.5% and 69.7% of brilliant green (BG) and 4-nitrophenol (4-NP) were degraded with rate of degradation which were 0.0281 and 0.011 min−1.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Nguyen Thi Truc Linh ◽  
Phan Dinh Tuan ◽  
Nguyen Van Dzung

The titania/hydroxyapatite (TiO2/HAp) product was prepared by precipitating hydroxyapatite in the presence of TiO(OH)2 gel in the hydrothermal system. The characteristics of the material were determined by using the measurements such as X-ray photoemission spectroscopy (XPS), X-ray diffraction (XRD), diffuse reflectance spectra (DRS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX). The XPS analysis showed that the binding energy values of Ca (2p1/2, 2p3/2), P (2p1/2, 2p3/2), and O 1s levels related to hydroxyapatite phase whereas those of Ti (2p3/2, 2p1/2) levels corresponded with the characterization of titanium (IV) in TiO2. The XRD result revealed that TiO2/HAp sample had hydroxyapatite phase, but anatase or rutile phases were not found out. TEM image of TiO2/HAp product showed that the surface of the plate-shaped HAp particles had a lot of smaller particles which were considered as the compound of Ti. The experimental band gap of TiO2/HAp material calculated by the DRS measurement was 3.6 eV, while that of HAp pure was 5.3 eV and that of TiO2 pure was around 3.2 eV. The shift of the band gap energy of TiO2 in the range of 3.2–3.6 eV may be related to the shifts of Ti signals of XPS spectrum.


Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 749
Author(s):  
Zhongjin Ni ◽  
Xiaohai Cao ◽  
Xinyi Wang ◽  
Shiyu Zhou ◽  
Caixia Zhang ◽  
...  

In this thesis, Cu2O nanochains were synthesized by thermal decomposition with copper formate-octylamine as the precursor, oleic acid and oleylamine as the catalyst stabilizer agent and paraffin as the solvent. The phase structure and micromorphology of Cu2O nanochains were characterized by X-ray diffraction and transmission electron microscopy. The effect of reaction time and concentration of the precursor on the Cu2O nanochains were discussed, and the formation mechanism of the Cu2O nanochains was analyzed. The results show that Cu2O nanochains were self-assembled by Cu2O nanocrystals; with the extension of the reaction time, Cu2O nanochains gradually become granular; increasing the concentration of the precursor will increase the entanglement degree of the nanochains. Oleic acid contributes to the formation of Cu2O, and oleylamine plays a directional role in the formation of nanochains. On the basis of those phenomenon, a comparison of the Cu2O nanochain-water nanofluids with that of a water-based liquid showed that after irradiating for 3000 s, the temperature of nanofluids reached 91.1 °C while the water was only 75.7 °C. This demonstrates the better performance of the Cu2O nanochain-water nanofluid in the ability of light absorption, thermal conductivity and photothermal conversion.


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