scholarly journals Facile Synthesis and Characterization of N-Doped TiO2Photocatalyst and Its Visible-Light Activity for Photo-Oxidation of Ethylene

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Yu-Hao Lin ◽  
Chih-Huang Weng ◽  
Arun Lal Srivastav ◽  
Yao-Tung Lin ◽  
Jing-Hua Tzeng
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Oxidation ◽  
Precursor Solution ◽  
Ammonium Hydroxide ◽  
Titanium Isopropoxide ◽  
Light Region ◽  
Light Activity ◽  
Different Temperatures ◽  
N Doping

A facile wet chemical method was adopted for preparing highly photoactive nitrogen doped TiO2(N-TiO2) powders with visible responsive capability, which could be achieved by the hydrolysis of titanium isopropoxide (TTIP) in the ammonium hydroxide precursor solution in various concentrations and then calcined at different temperatures. The N-TiO2powders were characterized, and the photocatalytic activity was evaluated for the photocatalytic oxidation of ethylene gas under visible light irradiation to optimize the synthesizing conditions of N-TiO2catalyst. The N-TiO2photocatalytic powders were calcined in a range of temperatures from 300 to 600°C and obviously found to have greater photocatalytic activities than commercial TiO2P25. The strong absorption in the visible light region could be ascribed to good crystallization and adapted sinter temperature of as prepared sample. XPS test demonstrated that the N was doped into TiO2lattice and made an interstitial formation (Ti-O-N), and N doping also retarded the phase transformation from anatase to rutile as well. The N-TiO2catalyst prepared with 150 mL ammonium hydroxide added and calcined at 500°C showed the best photocatalytic activity. The experimental results also proved the enhanced photoactivity of N-TiO2material depends on the synthesizing conditions.

scholarly journals N-Doped K3Ti5NbO14@TiO2 Core-Shell Structure for Enhanced Visible-Light-Driven Photocatalytic Activity in Environmental Remediation

Catalysts ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 106 ◽  
Author(s):  
Xin Gao ◽  
Chen Wang ◽  
Qixiang Xu ◽  
Hongjie Lv ◽  
Ting Chen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Environmental Remediation ◽  
Titanium Isopropoxide ◽  
Core Shell ◽  
Xps Spectra ◽  
X Ray ◽  
Visible Light Driven ◽  
N Doping

A novel N-doped K3Ti5NbO14@TiO2 (NTNT) core-shell heterojunction photocatalyst was synthesized by firstly mixing titanium isopropoxide and K3Ti5NbO14 nanobelt, and then calcinating at 500 °C in air using urea as the nitrogen source. The samples were analyzed by X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-Vis absorption spectroscopy and X-ray photoelectron spectroscopic (XPS) spectra. Anatase TiO2 nanoparticles were closely deposited on the surface of K3Ti5NbO14 nanobelt to form a nanoscale heterojunction structure favorable for the separation of photogenerated charge carriers. Meanwhile, the nitrogen atoms were mainly doped in the crystal lattices of TiO2, resulting in the increased light harvesting ability to visible light region. The photocatalytic performance was evaluated by the degradation of methylene blue (MB) under visible light irradiation. The enhanced photocatalytic activity of NTNT was ascribed to the combined effects of morphology engineering, N doping and the formation of heterojunction. A possible photocatalytic mechanism was proposed based on the experimental results.

Experimental Research of Visible Light-Induced Photocatalytic Oxidation Effects of SO2 by N-Doping Nano-TiO2

2012 ◽  
Vol 486 ◽  
pp. 12-17
Author(s):  
Shu Qin Wang ◽  
Yin Tao Wang ◽  
Yan Dong Liu
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Oxidation ◽  
Sol Gel ◽  
Particle Diameter ◽  
Experimental Conditions ◽  
N Doping ◽  
Photocatalytic Reactions ◽  
Oxidation Mechanisms ◽  
Lamp Illumination

N-doping nanoTiO2 was prepared by sol-gel method. The TEM,XRD,XPS,BET and UV techniques were used to characterize the crystalline structure.The photocatalytic oxidation effects of SO2 were studied with the fluorescence lamp illumination under the different conditions. The visible light-induced photocatalytic oxidation mechanisms of SO2 were discussed. The results showed that N-doping nanoTiO2 increase the visible-light responsive photocatalytic activity because of the increase of the surface area, O2 lacuna and small particle diameter. There are the optima of the dosage and amount of O2. The removal efficiency of SO2 was greater than 95% under the experimental conditions. The photocatalytic reactions of SO2 included two parts-adsorption and oxidation. The results provide some references for the SO2 control and further application of nanoTiO2.

Visible-Light Activity Evaluation of p-n Junction Photocatalyst NiO/TiO2 Prepared by Sol-Gel Method

2010 ◽  
Vol 152-153 ◽  
pp. 441-449 ◽  
Author(s):  
Wei Liu ◽  
Shi Fu Chen
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Oxidation ◽  
Raw Materials ◽  
Sol Gel ◽  
Visible Region ◽  
Tetrabutyl Titanate ◽  
Gel Method ◽  
Sol Gel Method ◽  
Light Activity

P-N junction photocatalyst NiO/TiO2 photoexcited by visible light was prepared by sol-gel method using Ni(NO3)2•6H2O and tetrabutyl titanate [Ti(OC4H9)4] as the raw materials. The p-n junction photocatalyst NiO/TiO2 was characterized by UV-Vis diffuse reflection spectrum, fluorescence spectra (FL), X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). UV-Vis spectrum showed that the absorption wavelength range of NiO/TiO2 is extended to the visible region, making it an effective photocatalyst photoexcited by visible light. This was demonstrated by photocatalytic reduction of Cr2O72- and photocatalytic oxidation of methyl orange (MO) under visible-light (λ>400 nm) irradiation. Doped-NiO effectively suppressed the phase transformation of anatase to rutile and the growth of titania crystallites. The optimum percentage of doped NiO is 0.5% (mole ratio of Ni/Ti). Effects of heat treatment on the photocatalytic activity of p-n junction photocatalyst NiO/TiO2 were investigated. The mechanisms of influence on the photocatalytic activity were also discussed by the p-n junction principle.

Preparation and Properties of Titanium Oxide Photocatalyst with Visible Light Activity

2007 ◽  
Vol 280-283 ◽  
pp. 377-380 ◽  
Author(s):  
Lei E ◽  
Ming Xia Xu ◽  
Lei Ge ◽  
Yu Ming Tian ◽  
Yan Li ◽  
...  
Keyword(s):  
Visible Light ◽  
Ph Value ◽  
Uv Light ◽  
Hydrolysis Product ◽  
Treatment Temperature ◽  
Absorption Feature ◽  
Visible Light Region ◽  
Light Region ◽  
Light Activity ◽  
Different Temperatures

TiO2 photocatalyst were obtained from the hydrolysis product of TiOSO4 with ammonia and the photocatalytic activities were investigated by the photocatalytic degradation of methyl orange aqueous solution under UV-light and visible-light. The results showed that the absorption intensity in visible-light was dependent on the concentration of the materials, pH value and heat-treatment temperature. The color of the TiO2 varied from yellowish to vivid yellow when the TiO2 was calcined at different temperatures from 300°C to 500°C for 1h. The photocatalytic activity of TiO2 under visible light was determined by the photo-absorption feature in visible light region, which was related to the heattreatment temperature. The TiO2 calcined at 400°C shows stronger photo-absorption in visible light region and exhibits higher visible-light activity than the TiO2 calcined at other temperature.

PEG-Assisted Hydrothermal Synthesis and Photocatalytic Activity of Bi2Fe4O9 Crystallites

2011 ◽  
Vol 1292 ◽  
Author(s):  
Dengrong Cai ◽  
Jianmin Li ◽  
Shundong Bu ◽  
Shengwen Yu ◽  
Dengren Jin ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Diffuse Reflectance Spectrum ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
Peg 400 ◽  
Transmission Electron ◽  
Light Region ◽  
Facile Hydrothermal Route ◽  
Degradation Ratio

ABSTRACTA facile hydrothermal route assisted by polyethylene glycol (PEG) 400 was utilized to synthesize single-phase Bi2Fe4O9 crystallites. X-ray diffraction results showed the products with PEG 400 of 30 g/L exhibited a preferred growth along the (001) plane. Transmission electron microscopy indicated that the morphology of the as-prepared Bi2Fe4O9 crystallites with PEG 400 were plake-like and rod-like. Strong absorption in visible-light region of the products was characterized by UV-vis diffuse reflectance spectrum (UV-DRS). The photocatalytic activity of Bi2Fe4O9 crystallites was evaluated on degradation of methyl orange (MO) under visible light irradiation. For 3 h irradiation, the degradation ratio was increased to 93% with the aid of a small amount of H2O2. The analysis of FT-IR spectra proved that the Bi2Fe4O9 catalysts were remained stable after the photocalytic reactions.

scholarly journals SOLVOTHERMAL SYNTHESIS OF BI2WO6 AND ITS PHOTOCATALYTIC ACTIVITY UNDER VISIBLE LIGHT IRRADIATION

2018 ◽  
Vol 54 (4B) ◽  
pp. 42
Author(s):  
Trinh Duy Nguyen
Keyword(s):  
Absorption Spectrum ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Solvothermal Synthesis ◽  
Solvothermal Method ◽  
Visible Region ◽  
High Photocatalytic Activity ◽  
Light Irradiation ◽  
Different Temperatures

Flower-like Bi2WO6 were successfully synthesized using the solvothermal method at different temperatures and characterized by XRD, FE-SEM, and DRS. We also investigated the photocatalytic activity of Bi2WO6 for the decomposition of rhodamine B under visible light irradiation. From XRD and SEM results, the reaction temperature has significant effects on the morphologies of the samples. From DRS results, Bi2WO6 samples displayed the absorption spectrum up to the visible region and then they showed the high photocatalytic activity under visible light irradiation, as a comparison with TiO2-P25.

Ultrathin HNb3O8 nanosheets with oxygen vacancies for enhanced photocatalytic oxidation of amines under visible light irradiation

2019 ◽  
Vol 7 (10) ◽  
pp. 5493-5503 ◽  
Author(s):  
Junli Chen ◽  
Hai Wang ◽  
Zhiqiang Zhang ◽  
Lifeng Han ◽  
Yonghui Zhang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Photocatalytic Oxidation ◽  
Oxygen Vacancies ◽  
Hydrothermal Process ◽  
Light Irradiation ◽  
Excellent Photocatalytic Activity ◽  
Simple Hydrothermal Process

Ultrathin HNb3O8 nanosheets with oxygen vacancies were successfully synthesized by a simple hydrothermal process. HNb3O8 NSs showed excellent photocatalytic activity.

scholarly journals Preparation and Characterization of Defective TiO2. The Effect of the Reaction Environment on Titanium Vacancies Formation

Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2763
Author(s):  
Zuzanna Bielan ◽  
Szymon Dudziak ◽  
Agnieszka Sulowska ◽  
Daniel Pelczarski ◽  
Jacek Ryl ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Hydrothermal Reaction ◽  
High Photocatalytic Activity ◽  
Paramagnetic Resonance ◽  
X Ray ◽  
Light Activity ◽  
Cheap Alternative

Among various methods of improving visible light activity of titanium(IV) oxide, the formation of defects and vacancies (both oxygen and titanium) in the crystal structure of TiO2 is an easy and relatively cheap alternative to improve the photocatalytic activity. In the presented work, visible light active defective TiO2 was obtained by the hydrothermal reaction in the presence of three different oxidizing agents: HIO3, H2O2, and HNO3. Further study on the effect of used oxidant and calcination temperature on the physicochemical and photocatalytic properties of defective TiO2 was performed. Obtained nanostructures were characterized by X-ray diffractometry (XRD), specific surface area (BET) measurements, UV-Vis diffuse reflectance spectroscopy (DR-UV/Vis), photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) spectroscopy. Degradation of phenol as a model pollutant was measured in the range of UV-Vis and Vis irradiation, demonstrating a significant increase of photocatalytic activity of defective TiO2 samples above 420 nm, comparing to non-defected TiO2. Correlation of EPR, UV-Vis, PL, and photodegradation results revealed that the optimum concentration of HIO3 to achieve high photocatalytic activity was in the range of 20–50 mol%. Above that dosage, titanium vacancies amount is too high, and the obtained materials’ photoactivity was significantly decreased. Studies on the photocatalytic mechanism using defective TiO2 have also shown that •O2− radical is mainly responsible for pollutant degradation.

scholarly journals Tuning the Morphological Structure and Photocatalytic Activity of Nitrogen-Doped (BiO)2CO3by the Hydrothermal Temperature

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Chongjun Wang ◽  
Zaiwang Zhao ◽  
Bin Luo ◽  
Min Fu ◽  
Fan Dong
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Light Absorption ◽  
Photocatalytic Performance ◽  
Morphological Structure ◽  
Hydrothermal Temperature ◽  
Nitrogen Doped ◽  
Light Region ◽  
Efficient Performance ◽  
One Step

Various nitrogen-doped hierarchical (BiO)2CO3nanosheets architectures were synthesized by a facile one-step template-free hydrothermal method through controlling the hydrothermal temperature (HT). The as-synthesized samples were characterized by XRD, SEM, FT-IR, XPS, and UV-vis DRS. The photocatalytic activity of the samples was evaluated towards degradation of NO at ppb level in air under visible light (VIL). It was found that HT acted as a crucial factor in determining the morphology of the samples. The rosa chinensis-like, red camellia-like, and lamina-like of nitrogen-doped (BiO)2CO3(N-BOC) micro-/nanostructures can be selectively fabricated under hydrothermal temperatures of 150, 180, and 210°C. The thickness of the nanosheets was in direct proportion to the increasing HT. Nitrogen-doping can extend the light absorption spectra of (BiO)3CO3to visible light region and enhance the VIL photocatalytic activity. Especially, the red camellia-like N-BOC-180 exhibited the highest photocatalytic performance, superior to the well-known VIL-driven photocatalyst C-doped TiO2and N-doped TiO2. The high photocatalytic performance of N-BOC was attributed to the synergetic effects of enhanced visible light absorption, multiple light-reflections between the nanosheets, and accelerated transfer of reactants and product. This research could provide new insights to the development of excellent photocatalyst with efficient performance for pollution control.

Photocatalytic properties of Bi/BiOCl heterojunctions synthesized using an in situ reduction method

2014 ◽  
Vol 38 (10) ◽  
pp. 4913-4921 ◽  
Author(s):  
Jiajia Hu ◽  
Guangqing Xu ◽  
Jinwen Wang ◽  
Jun Lv ◽  
Xinyi Zhang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Reduction Method ◽  
Uv Light ◽  
Photocatalytic Properties ◽  
In Situ Reduction ◽  
Light Activity ◽  
Bi Nanoparticles

Bi nanoparticles on BiOCl nanosheets, synthesized via in situ reduction, enhance the UV light photocatalytic activity and achieve visible light activity.

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