Changing width bandgap of TiO2 nanoparticles incorporating GO

MRS Advances ◽  
2019 ◽  
Vol 4 (61-62) ◽  
pp. 3423-3431
Author(s):  
Daniela K. Calvo-Ramos ◽  
Marina Vega-González ◽  
José Santos-Cruz ◽  
Francisco Javier De Moure-Flores ◽  
Sandra A. Mayén-Hernández
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Graphene Oxide ◽  
Nir Spectroscopy ◽  
Improved Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

ABSTRACTNanoparticles of titanium dioxide (TiO2), synthesized by the sonochemical technique, were mixed with different amounts of graphene oxide (GO), obtained by the improved method of Hummer, in order to modify their bandwidth. The TiO2/OG compounds were characterized using different techniques: X-ray Diffraction (XRD), transmission electron microscopy (TEM), Raman and UV-Vis-NIR spectroscopy. TiO2 bandgap decreased, with GO incorporation, from 3.2 to 2.72 eV when GO was present at 20 weigh percentage (TiO2/GO-20%). Photodegradation experiments of methylene blue (MB) were performed with the materials to verify their photocatalytic activity. At 40 minutes, the pure TiO2 degraded 48% of MB, whereas the compound TiO2/GO-20% degraded 88%, showing a good incorporation of both compounds and the improvement of TiO2 photocatalitic properties.

BiVO4/MIL-101 composite having the synergistically enhanced visible light photocatalytic activity

RSC Advances ◽  
2015 ◽  
Vol 5 (54) ◽  
pp. 43473-43479 ◽  
Author(s):  
Yanli Xu ◽  
Mengmeng Lv ◽  
Hanbiao Yang ◽  
Qi Chen ◽  
Xueting Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Photocatalytic Activity ◽  
Thermogravimetric Analysis ◽  
Diffuse Reflectance ◽  
Emission Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Visible Light Photocatalytic

The BiVO4/MIL-101 composite and pure materials were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, UV-vis diffuse reflectance absorption spectra and photoluminescence emission spectra.

TEMPLATE STRATEGY FOR THE SYNTHESIS OF Cu2O–Pt HIERARCHICAL HETEROSTRUCTURES FOR THE DEGRADATION OF METHYLENE BLUE

NANO ◽  
2013 ◽  
Vol 08 (06) ◽  
pp. 1350062 ◽  
Author(s):  
SHIYONG BAO ◽  
HAN ZHU ◽  
PAN WANG ◽  
MEILING ZOU ◽  
MINGLIANG DU ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Methylene Blue ◽  
Photoelectron Spectroscopy ◽  
Pt Nanoparticles ◽  
X Ray Diffraction ◽  
Electron Hole ◽  
X Ray ◽  
Transmission Electron ◽  
Green Route

A facile and green route was introduced to synthesize Pt nanoparticles (PtNPs) immobilized on Cu 2 O octahedrons to form Cu 2 O – Pt hierarchical heterostructure. Transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were employed to study their morphology, chemical and crystallographic properties of the Cu 2 O – Pt hierarchical heterostructure. These novel Cu 2 O – Pt hierarchical heterostructures show fascinating degradations of methylene blue (MB), due to the suppressed electron/hole recombination phenomena and the efficient ability to capture the light.

Optical and photocatalytic properties of photoactive paper with polycrystalline TiO2 nanopigment for optimal product design

TAPPI Journal ◽  
2012 ◽  
Vol 11 (5) ◽  
pp. 33-38 ◽  
Author(s):  
SEONGHYUK KO ◽  
PAUL D. FLEMING ◽  
MARGARET JOYCE ◽  
PNINA ARI-GUR
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gas Chromatography ◽  
Titanium Dioxide ◽  
Optical Properties ◽  
Photocatalytic Activity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Optimal Product Design

We investigated the effect of the crystalline phases of titanium dioxide nanopigment to optimize the optical properties and photocatalytic activity for synthesizing a photoactive paper. Six different ratios of anatase to rutile were prepared. Phase change and particle size were characterized using X-ray diffraction and transmission electron microscopy. Optical properties including opacity and brightness were tested. Photocatalytic activity was evaluated by measuring toluene decomposition, using gas chromatography. A specific ratio between two different crystallites of titanium dioxide showed relatively better optical and photoactive properties. The optimal anatase-to-rutile ratio was found to be 0.52:0.48.

Characterization and Photocatalytic Activity of La1.6Ln0.4Zr2O7 (Ln= La, Nd, Dy, Er) Nanocrystals by Stearic Acid Method

2010 ◽  
Vol 123-125 ◽  
pp. 631-634 ◽  
Author(s):  
Yu Ping Tong ◽  
Shun Bo Zhao ◽  
Feng Lan Li ◽  
Chang Yong Li
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Photocatalytic Activity ◽  
Stearic Acid ◽  
Nitrogen Adsorption ◽  
Combustion Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Degradation Of Methyl Orange

La1.6Ln0.4Zr2O7 (Ln= La, Nd, Dy, Er) nanocrystals were prepared by stearic acid combustion method. The samples were characterized by powder X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) nitrogen adsorption, transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The photocatalytic activity of La1.6Ln0.4Zr2O7 was evaluated by the photocatalytic degradation of methyl orange. The order of the photocatalytic activity was as following: La1.6Er0.4Zr2O7>La1.6Dy0.4Zr2O7> La1.6Nd0.4Zr2O7> La2Zr2O7. La1.6Dy0.4Zr2O7 showed that the best photocatalytic activity and the reason may be related to the big magnetic moment of Er3+. It may be considered largely to be caused by the partly occupied Ln4f levels. Since the solid samples have the same structure, the reason that La1.6Er0.4Zr2O7 shows the highest reactivity may be related to lowest Ln4f level of Er3+.

A novel synthetic method for nanosized crystalline titania for use in the decomposition of dyes

2004 ◽  
Vol 49 (4) ◽  
pp. 177-181 ◽  
Author(s):  
C.Y. Yun ◽  
J. Moon ◽  
K. Chung ◽  
M. Kang ◽  
C.B. Shin ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Photocatalytic Activity ◽  
Hydrothermal Process ◽  
Synthetic Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nanocrystalline Titania ◽  
Transmission Electron ◽  
Bet Method

Photocatalytically active nanocrystalline titania particles were prepared using a hydrothermal process, by controlling the particle size and crystallinity. The crystalline structures and morphologies of the particles were characterized by X-ray diffraction and transmission electron microscopy. The BET method was used to determine the surface area and verify the grain size. To estimate the photocatalytic activity of the synthesized particles, a dye photodegradation experiment was carried out and the activity of the particles was compared with that of conventional titania. The results show that synthesized nanocrystalline titania particles had a higher photocatalytic activity than that of conventional titania. These findings provide a basis for the preparation of more effective and useful materials for use in AOP applications.

Preparation, Characterization of N-Ti-MCM-22 Molecular Sieve and its Photocatalytic Properties

2012 ◽  
Vol 602-604 ◽  
pp. 205-208
Author(s):  
Yue Cheng ◽  
Xiao Yuan Su
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Methylene Blue ◽  
High Pressure ◽  
Liquid Phase ◽  
Molecular Sieve ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

Nanocrystalline N-doped and Ti-containing MCM-22 catalyst was synthesized by the static hydrothermal method, using sodium azide as nitrogen source for doping, and tetra-n-butyl titanate [Ti(OC4H9)4] as precursors of TiO2. The catalysts were characterized by X-ray diffraction, transmission electron microscopy, and energy-dispersive spectroscopy.During liquid phase photocatalytic degradation of methylene blue (MB) under high-pressure Hg arc lamp irradiation, the asprepared N-doped Ti-MCM-22 exhibited much higher activity than the undoped Ti-MCM-22, attributed to the effect of nitrogen dopant.

scholarly journals Photodecomposition of methylene blue over EGZrO2/HY in aqueous alkaline solution

2014 ◽  
Vol 7 (2) ◽  
Author(s):  
N. Sapawe ◽  
A. A. Jalil ◽  
S. Triwahyono
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Methylene Blue ◽  
Alkaline Solution ◽  
Dark Condition ◽  
X Ray Diffraction ◽  
Aqueous Alkaline Solution ◽  
X Ray ◽  
Transmission Electron ◽  
Methylene Violet

The photodecomposition of methylene blue (MB) in an aqueous alkaline solution over EGZrO2/HY catalyst was investigated. The prepared catalyst was examined using X–ray diffraction (XRD) and transmission electron microscopy (TEM). The MB was completely decolorized under visible light at pH 11 after 432 h over 1 wt% EGZrO2/HY photocatalyst. Photolysis almost did not occurs even the MB was kept for the same reaction time but when the system was kept under dark condition in the absence of catalyst the MB converted into methylene violet (MV) after 30 h of reaction.

The Microwave Synthesis and Photocatalytic Activity of ZnO/TiO2 Nanocomposites

2013 ◽  
Vol 651 ◽  
pp. 187-192 ◽  
Author(s):  
Gang Cheng Zhou ◽  
Quan Xin Zhu ◽  
Wan Qing Xiong ◽  
Jian Lei ◽  
Wen Xiang Ye ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Transmission Electron Microscopy ◽  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Microwave Irradiation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Degradation Ratio

ZnO/TiO2 nanocomposites were prepared by mixing of ultrasonic vibration and sintering at 500°C for 2 h initial nano-ZnO and nano-TiO2 which were synthesized by a microwave irradiation heating technique from an aqueous solution of Zn(Ac)2•2H2O, Ti(SO4)2, respectively. The samples were characterized by the techniques of X-ray diffraction (XRD) and transmission electron microscopy (TEM). And we have also carried on research to the photocatalytic activity of the as-prepared ZnO/TiO2 nanocomposites by photo-degrading methyl orange. The result indicates that the as-prepared sample is a good photocatalyst. When m (TiO2) /m (ZnO) ratio was equal to 4, the photocatalytic activity of the nanocomposites is best. The result shows that the degradation ratio of the methyl orange (2mg/L) has reached 93% within 80 min

A High Resolution Study of G.P. Zones in Aluminum - 4.2 at % Silver

1982 ◽  
Vol 40 ◽  
pp. 722-723 ◽  
Author(s):  
R. Gronsky
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Computer Simulations ◽  
Structural Characteristics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Resolution Study

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.

scholarly journals Quartz Crystallite Size and Moganite Content as Indicators of the Mineralogical Maturity of the Carboniferous Chert: The Case of Cherts from Eastern Asturias (Spain)

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 611
Author(s):  
Celia Marcos ◽  
María de Uribe-Zorita ◽  
Pedro Álvarez-Lloret ◽  
Alaa Adawy ◽  
Patricia Fernández ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Crystallite Size ◽  
Archaeological Sites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Infrared And Raman Spectroscopy ◽  
First Time ◽  
Geological Formations

Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.

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