scholarly journals Molten-Salt Flux Mediated Synthesis of ZnO-SnO2 Composites: Effects of Surface Areas and Crystallinities on Photocatalytic Activity

2020 ◽  
Author(s):  
Rachelle Austin ◽  
Feier Hou
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Surface Area ◽  
Salt Flux ◽  
Blue Dye ◽  
Synthetic Approach ◽  
Flux Synthesis ◽  
Surface Areas ◽  
Photocatalytic Activities ◽  
Two Factors

In this study, ZnO-SnO2 composites were synthesized using flux synthesis, a synthetic approach different from previous studies, in which molten ZnCl2 acted both as a reactant and as the flux for the reaction. Their photocatalytic properties were measured for the degradation of the organic dye, methylene blue. It was found that as the temperatures of the synthesis increase, the specific surface areas of the ZnO-SnO2 composites decrease, which would decrease their photocatalytic activities due to decreased adsorption of the dye on the surface of the composites; while their crystallinity increases, which would increase their photocatalytic activities due to the smaller concentration of defects and thus improved mobility of the charge carriers. An interplay of those two factors affects their photocatalytic activities, with the composite with the highest photocatalytic activity degrading approximately 95% of the methylene blue dye within 10 minutes. By changing the temperature of the flux synthesis alone, the crystallinity and surface area of the ZnO-SnO2 composite can be changed, which provides a possible way to obtain ZnO-SnO2 composites with relatively high crystallinity and surface area to maximize their photocatalytic activity.

scholarly journals Molten-Salt Flux Mediated Synthesis of ZnO-SnO2 Composites: Effects of Surface Areas and Crystallinities on Photocatalytic Activity

2020 ◽  
Author(s):  
Rachelle Austin ◽  
Feier Hou
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Surface Area ◽  
Salt Flux ◽  
Blue Dye ◽  
Synthetic Approach ◽  
Flux Synthesis ◽  
Surface Areas ◽  
Photocatalytic Activities ◽  
Two Factors

In this study, ZnO-SnO2 composites were synthesized using flux synthesis, a synthetic approach different from previous studies, in which molten ZnCl2 acted both as a reactant and as the flux for the reaction. Their photocatalytic properties were measured for the degradation of the organic dye, methylene blue. It was found that as the temperatures of the synthesis increase, the specific surface areas of the ZnO-SnO2 composites decrease, which would decrease their photocatalytic activities due to decreased adsorption of the dye on the surface of the composites; while their crystallinity increases, which would increase their photocatalytic activities due to the smaller concentration of defects and thus improved mobility of the charge carriers. An interplay of those two factors affects their photocatalytic activities, with the composite with the highest photocatalytic activity degrading approximately 95% of the methylene blue dye within 10 minutes. By changing the temperature of the flux synthesis alone, the crystallinity and surface area of the ZnO-SnO2 composite can be changed, which provides a possible way to obtain ZnO-SnO2 composites with relatively high crystallinity and surface area to maximize their photocatalytic activity.

Comparison of Adsorption Capability and Photocatalytic Activity for Methylene Blue Decomposition of LiInO2 with NaInO2

2006 ◽  
Vol 317-318 ◽  
pp. 819-822
Author(s):  
Jun Hu Wang ◽  
Toru Nonami
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Fine Particles ◽  
Composite Particles ◽  
Blue Dye ◽  
Methylene Blue Dye ◽  
Co Catalyst ◽  
Photocatalytic Activities ◽  
Adsorption Capability

In the present study, Pt, NiO, and RuO2 fine particles as co-catalyst were loaded on the LiInO2 surface by different methods for enhancing its adsorption capability and photocatalytic activity for methylene blue dye (MB) decomposition. Clear adsorption capability and marked photocatalytic activity for MB decomposition were confirmed on the co-catalyst loaded LiInO2 composite particles. Comparing with that of LiINO2, the previously reported NaInO2 photocatalyst had stronger adsorption capability and higher photocatalytic activity. However, the adsorption capabilities and the photocatalytic activities were separately in the same order of RuO2/AInO2 > Pt/AInO2 > AInO2 > NiO/AInO2 and Pt/LiInO2 > RuO2/LiInO2 > NiO/LiInO2 > LiInO2 for the two promising AInO2 (A = Li+ or Na+) photocatalyst.

Photocatalytic Activities of Mo Ions Implanted TiO2 Thin Films

2011 ◽  
Vol 335-336 ◽  
pp. 1508-1511
Author(s):  
Shu Kai Zheng
Keyword(s):  
Thin Films ◽  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Optimal Dose ◽  
Blue Dye ◽  
Methylene Blue Dye ◽  
X Ray Diffraction ◽  
X Ray ◽  
Glass Slides ◽  
Photocatalytic Activities

Transparent TiO2 thin films were deposited onto microscope glass slides by means of d.c. magnetron sputtering method. In order to enhance the photocatalytic activity of TiO2 thin films, Mo ions with different nominal doses were implanted into the TiO2 thin films. The samples were characterized by different technologies including X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS) and UV-VIS-NIR spectrophotometer. The photodegradation results of methylene blue dye solution indicated that optimal dose of 2×1012ions/cm2 Mo ion-implantation resulted in a higher photocatalytic activity in the implanted TiO2 thin films.

scholarly journals Highly Porous and Ultra-Lightweight Aero-Ga2O3: Enhancement of Photocatalytic Activity by Noble Metals

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1985
Author(s):  
Irina Plesco ◽  
Vladimir Ciobanu ◽  
Tudor Braniste ◽  
Veaceslav Ursaki ◽  
Florian Rasch ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Noble Metals ◽  
Hybrid Structures ◽  
Blue Dye ◽  
Light Illumination ◽  
Methylene Blue Dye ◽  
Visible Light Illumination ◽  
New Type ◽  
Highly Porous

A new type of photocatalyst is proposed on the basis of aero-β-Ga2O3, which is a material constructed from a network of interconnected tetrapods with arms in the form of microtubes with nanometric walls. The aero-Ga2O3 material is obtained by annealing of aero-GaN fabricated by epitaxial growth on ZnO microtetrapods. The hybrid structures composed of aero-Ga2O3 functionalized with Au or Pt nanodots were tested for the photocatalytic degradation of methylene blue dye under UV or visible light illumination. The functionalization of aero-Ga2O3 with noble metals results in the enhancement of the photocatalytic performances of bare material, reaching the performances inherent to ZnO while gaining the advantage of the increased chemical stability. The mechanisms of enhancement of the photocatalytic properties by activating aero-Ga2O3 with noble metals are discussed to elucidate their potential for environmental applications.

scholarly journals Photocatalytic activity of CaTaO2N nanocrystals obtained from a hydrothermally synthesized oxide precursor

2019 ◽  
Author(s):  
Roberto Köferstein
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Specific Surface ◽  
Morphological Properties ◽  
Soft Chemistry ◽  
Co Catalyst ◽  
Surface Areas ◽  
Oxide Precursor ◽  
Photocatalytic Activities ◽  
Specific Surface Areas

Highly crystalline CaTaO2N nanoparticles possessing large specific surface areas were investigated as photocatalysts for the decomposition of methyl orange. Two different Ca2Ta2O7 precursors were synthesized by classical solid state synthesis and a hydrothermal soft-chemistry approach, respectively. In both cases, nitridation was carried out by thermal ammonolysis. The obtained CaTaO2N samples were compared with respect to their optical, thermal and morphological properties as well as their photocatalytic activities. In particular, the influence of ammonolysis temperature on the photocatalytic properties was studied. Using hydrothermally synthesized Ca2Ta2O7, phase pure CaTaO2N was obtained already at a relatively low ammonolysis temperature of 860 °C. Morphological investigations show that the CaTaO2N samples from the hydrothermally synthesized precursor consist of single-crystalline particles of 45 to 70 nm diameter with high specific surface areas between 12 and 19 m2 g-1, depending on ammonolysis temperature. A considerable photocatalytic activity for methyl orange degredation was found for the nanoscaled CaTaO2N particles prepared at lower ammonolysis temperatures. Using CoOx as co-catalyst, a further strong enhancement of the methyl orange decomposition by a factor 5-10 was achieved.

Effect of Iron (III)-Doping on the Photocatalytic Activity of Titanium Dioxide Catalysts for Methylene Blue Degradation

2011 ◽  
Vol 117-119 ◽  
pp. 1088-1091
Author(s):  
Wen Churng Lin ◽  
Rui Liu ◽  
Wein Duo Yang
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Specific Surface ◽  
Effective Means ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Surface Areas ◽  
Bet Specific Surface Area ◽  
Vis Spectroscopy

Iron-doped TiO2 photocatalyst powders were prepared by the sol–gel method and characterized by Brunauer–Emmett–Teller (BET)-specific surface area, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Ultraviolet–Visible (UV-Vis) spectroscopy. Fe3+ doping in the TiO2 decreases the crystal grain size, increases the specific surface areas of powders, extends the absorption to visible light regions (400~500 nm), and lowers the photocatalytic activity for methylene blue (MB) degradation under UV irradiation. The photocatalytic degradation of MB in water was investigated as a function of the Fe3+ content in TiO2. It was found that under the irradiation of visible light, a small amount of Fe3+ dopant in TiO22 powders could obviously enhance the photocatalytic activity. When the Fe3+ content was in the range of 0.03–0.1 mol%, the photocatalytic activity of the samples was higher than that of undoped TiO2. Appropriate content of Fe-doping is an effective means to improve the photocatalytic activity of TiO2 for MB degradation under visible light irradiation.

Bi2WO6 Nanoparticles Prepared by Combustion Synthesis with Different Fuels and their Photocatalytic Activity

2014 ◽  
Vol 604 ◽  
pp. 93-101
Author(s):  
Maris Kodols ◽  
Sabine Didrihsone ◽  
Janis Grabis
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Citric Acid ◽  
Ethylene Glycol ◽  
Specific Surface ◽  
Crystallite Size ◽  
Combustion Synthesis ◽  
Surface Area ◽  
Specific Surface Area ◽  
Solution Ph

The influence of glycine, glycerine, ethylene glycol and citric acid fuel and their ratio to NO3- on formation and dispersity of Bi2WO6 nanoparticles prepared by combustion synthesis has been studied. The pure crystalline Bi2WO6 with specific surface area 24,8 m2/g and crystallite size of 28 nm was obtained by using glycerine as fuel at its ratio to NO3- of 0,67. The photocatalytic activity of the prepared Bi2WO6 in degradation of methylene blue depended on its specific surface area of samples and solution pH.

Sign in / Sign up

Export Citation Format

Share Document