Preparation of TiO2 Nanoparticle/Nanotube Composites via a Vapor Hydrolysis Method and Their Photocatalytic Activities

TiO2 nanoparticle/nanotube composites were prepared by a vapor hydrolysis method and were characterized by X-ray diffraction, transmission electron microscopy, and N2 isothermal adsorption-desorption. The well-crystallized TiO2 nanoparticles were uniformly deposited onto the surface of TiO2 nanotubes. The photocatalytic activity of the composites was evaluated by the degradation of acid red G and phenol solution under UV irradiation. The results showed that the photocatalytic activities of the modified composites were significantly enhanced compared to the pristine nanotubes. In particular, the 50 wt% TiO2 nanoparticle/nanotube composite obtained at 120°C exhibited a remarkable ARG degradation efficiency of 90% after irradiation for 30 minutes and a phenol degradation efficiency of 93% after irradiation for 2 hours.

Download Full-text

Comparison of TiO2/RH-MCM-41 and TiO2/TEOS-MCM-41 Hybrid Catalysts in Characteristics and Photodegradation of Tetramethylammonium

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.93-94.22 ◽

2010 ◽

Vol 93-94 ◽

pp. 22-26 ◽

Cited By ~ 1

Author(s):

Surachai Artkla ◽

Won Yong Choi ◽

Jatuporn Wittayakun

Keyword(s):

Irradiation Time ◽

Catalytic Performance ◽

X Ray Diffraction ◽

N2 Adsorption ◽

X Ray ◽

Transmission Electron ◽

Photocatalytic Activities ◽

Adsorption Desorption ◽

Two Hybrid ◽

Mcm 41

This work compared properties and catalytic performance of two hybrid photocatalysts, TiO2/RH-MCM-41 and TiO2/TEOS-MCM-41 prepared by loading nanoparticles of TiO2 (10 wt.%) on MCM-41 synthesized with rice husk silica and tetraethyl orthosilicate respectively. The supports and catalysts were characterized by X-ray diffraction, N2 adsorption-desorption, transmission electron microscopy and zeta potential. The photocatalytic activities of the TiO2/RH-MCM-41 and TiO2/TEOS-MCM-41 for the degradation of tetramethylammonium (TMA) in aqueous slurry were similar with a complete conversion after irradiation time of 90 min at pH 7.

Download Full-text

Synthesis and photocatalytic activities of Nd-doped TiO2 mesoporous microspheres

Functional Materials Letters ◽

10.1142/s1793604716500132 ◽

2016 ◽

Vol 09 (01) ◽

pp. 1650013 ◽

Cited By ~ 6

Author(s):

Xijian Liu ◽

Yangang Sun ◽

Yeying Wang ◽

Lijuan Zhang ◽

Jie Lu

Keyword(s):

Electron Microscopy ◽

Light Irradiation ◽

Xenon Lamp ◽

X Ray Diffraction ◽

Absorbance Spectroscopy ◽

Transmission Electron ◽

Mesoporous Microspheres ◽

Photocatalytic Activities ◽

Uv Visible ◽

Adsorption Desorption

Nd-doped TiO2 mesoporous microspheres with possessing regular micro/nanostructure were synthesized by a simple and facile method. The structure and optical properties of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption–desorption isotherms and UV-Visible absorbance spectroscopy. It was revealed that Nd-doped TiO2 mesoporous microspheres are composed of primary nanoparticles with a particle size of [Formula: see text]25[Formula: see text]nm. The photocatalytic activities of all the samples were evaluated by degradation methyl orange (MO) in aqueous solution as a model reaction under xenon lamp light irradiation. The results showed that the doped samples demonstrated a higher photocatalytic activity than TiO2 mesoporous microspheres, and the MO of 10[Formula: see text]mg/mL almost could be completely degraded by the Nd-doped TiO2 mesoporous sample (the dosage of Nd salt to TiO2 is 6%) under xenon lamp light irradiation within 1[Formula: see text]h.

Download Full-text

REMOVAL OF NORFLOXACIN BY TiO2-SBA-15 PHOTOCATALYST

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/58/3a/14229 ◽

2020 ◽

Vol 58 (3A) ◽

pp. 13

Author(s):

Nguyễn Thị Thu Trang ◽

Trần Quang Vinh ◽

Nguyễn Thành Đồng ◽

Phạm Tuấn Linh ◽

Nguyễn Viết Hoàng ◽

...

Keyword(s):

Uv Light ◽

Sol Gel ◽

X Ray Diffraction ◽

Surface Areas ◽

Pluronic P123 ◽

Adsorption Capacities ◽

Transmission Electron ◽

Photocatalytic Activities ◽

Adsorption Desorption ◽

Synthesized Materials

Ordered SBA-15 mesoporous silica support was synthesized by a sol-gel method using triblock copolymer Pluronic P123 and immobilized with different amounts of photocatalyst TiO2. The synthesized composites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and N2 adsorption-desorption isotherms. The synthesized materials possessed specific surface areas SBET of 768 m2/g, 544 m2/g, 421 m2/g and 333 m2/g at the TiO2:SiO2 ratio of 0, 0.25, 1.0 and 5.0, respectively. The adsorption capacities and photocatalytic activities under UV light irradiation of these materials were evaluated for Norfloxacin degradation. Experimental results indicate that the highest activity was observed on the sample with TiO2:SiO2 ratio of 1.

Download Full-text

Synthesis, Characterization and Photocatalytic Activity of AgCl Loaded on TiO2/SBA-15 Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.557-559.249 ◽

2012 ◽

Vol 557-559 ◽

pp. 249-253

Author(s):

Ge Er Yi ◽

Chun Fang Du ◽

Yi Guo Su ◽

Zhi Liang Liu

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Photocatalytic Decomposition ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Photocatalytic Activities ◽

The Matrix ◽

Photocatalytic Performances ◽

Adsorption Desorption

TiO2/SBA-15 and AgCl loaded on TiO2/SBA-15(AgCl-TiO2/SBA-15) composites were synthesized by a facile method. All products were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and N2adsorption-desorption analysis. Photocatalytic activities of the composites were assessed by the photocatalytic decomposition of methyl orange (MO). The results indicated that TiO2or TiO2-AgCl existed in the matrix SBA-15, which reduced the specific surface area, pore volume and pore size of the matrix. The photocatalytic performances of TiO2/SBA-15 were higher than that of pure TiO2, and the resultant AgCl-TiO2/SBA-15 composites showed much higher photocatalytic performances than TiO2/SBA-15.

Download Full-text

Synthesis of ZnO/ZnFe2O4 nanocomposites in organic-free media and their photocatalytic activity under natural sunlight

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.14.2.2020.20.0532 ◽

2020 ◽

Vol 14 (2) ◽

pp. 6801-6810

Author(s):

Rahmayeni Rahmayeni ◽

Zulhadjri Zulhadjri ◽

Yeni Stiadi ◽

Agusnar Harry ◽

Syukri Arief

Keyword(s):

Electron Microscopy ◽

Hexagonal Wurtzite Structure ◽

Rice Grain ◽

X Ray Diffraction ◽

Homogeneous Sphere ◽

Natural Sunlight ◽

Transmission Electron ◽

Photocatalytic Activities ◽

Free Media ◽

Photocatalytic Applications

Nanocomposite ZnO/ZnFe2O4 photocatalysts with different proportions of ZnFe2O4 were synthesized in organic-free media using metal nitric as precursors. The ZnO phase with hexagonal wurtzite structure and low crystallinity of ZnFe2O4 was confirmed using XRD (X-Ray diffraction). Different morphologies of the nanocomposites were obtained ranging from rice grain-like with a porous surface to homogeneous sphere-like nanoparticles as shown in Scanning Electron Microscopy (SEM) and TEM Transmission Electron Microscopy (TEM) studies. Magnetic properties measured by Visible Sampler Magnetometer (VSM) showed diamagnetic and paramagnetic behavior for the nanocomposites. Analysis with Diffuse Reflectance Spectrophotometer (DRS) UV-vis showed an increase the composition of ferrite in composites increasing its ability to absorb visible light. Photocatalytic activities of ZnO/ZnFe2O4 nanocomposites on the degradation of Rhodamine B dye reached 95.6% after 3 h under natural sunlight suggesting their suitability for sunlight driven photocatalytic applications.

Download Full-text

Hydrothermal Synthesis, Characterization and Exploration of Photocatalytic Activities of Polyoxometalate: Ni-CoWO4 Nanoparticles

Crystals ◽

10.3390/cryst11050456 ◽

2021 ◽

Vol 11 (5) ◽

pp. 456

Author(s):

Fahad A. Alharthi ◽

Hamdah S. Alanazi ◽

Amjad Abdullah Alsyahi ◽

Naushad Ahmad

Keyword(s):

Electron Microscopy ◽

Hydrothermal Synthesis ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Structure Morphology ◽

Photocatalytic Activities ◽

Ft Ir ◽

Photocatalytic Reactions ◽

Cobalt Tungstate

This study demonstrated the hydrothermal synthesis of bimetallic nickel-cobalt tungstate nanostructures, Ni-CoWO4 (NCW-NPs), and their phase structure, morphology, porosity, and optical properties were examined using X-ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy- energy dispersive X-ray spectroscopy (SEM-EDS), high resolution Transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) and Raman instruments. It was found that as-calcined NCW-NPs have a monoclinic phase with crystal size ~50–60 nm and is mesoporous. It possessed smooth, spherical, and cubic shape microstructures with defined fringe distance (~0.342 nm). The photocatalytic degradation of methylene blue (MB) and rose bengal (RB) dye in the presence of NCW-NPs was evaluated, and about 49.85% of MB in 150 min and 92.28% of RB in 90 min degraded under visible light. In addition, based on the scavenger’s study, the mechanism for photocatalytic reactions is proposed.

Download Full-text

Behaviours of direct yellow 12 adsorption on mesoporous carbons with different pore geometries

Water Science & Technology ◽

10.2166/wst.2018.104 ◽

2018 ◽

Vol 2017 (1) ◽

pp. 219-228

Author(s):

Fengling Liu ◽

Ziyan Guo ◽

Hui Qiu ◽

Xia Lu ◽

Hua Fang ◽

...

Keyword(s):

Mesoporous Carbons ◽

X Ray Diffraction ◽

Pore Characteristics ◽

X Ray ◽

Transmission Electron ◽

Cylindrical Pores ◽

Pseudo Second Order ◽

Hexagonally Ordered ◽

Adsorption Desorption ◽

Interconnected Pore

Abstract Four kinds of mesoporous carbons, C1-h-w, C2-h-h, C3-s-w, and C4-s-h, with different pore geometries were prepared and characterised, and their adsorption behaviours with aqueous direct yellow 12 (DY-12) were investigated. The results of X-ray diffraction and transmission electron microscopy show that C1-h-w and C3-s-w have wormlike pore characteristics, whereas C2-h-h and C4-s-h have 2-D hexagonally arranged pores. According to the N2 adsorption/desorption results, the specific surface area of C1-h-w (1,378 m2/g) is the largest among the four carbons. The adsorption isotherms could be effectively fitted using the Langmuir model. The maximum adsorption amounts of C1-h-w, C2-h-h, C3-s-w and C4-s-h are 0.968 mmol/g, 0.726 mmol/g, 0.161 mmol/g and 0.156 mmol/g, respectively. The pseudo-second-order rate constants of C1-h-w (39.8 g/(mmol·min)) and C2-h-h (7.28 g/(mmol·min)) are substantially larger than those of C3-s-w (0.0046 g/(mmol·min)) and C4-s-h (0.014 g/(mmol·min)), indicating that an open and interconnected pore geometry is favourable for DY-12 adsorption. Furthermore, DY-12 diffusion in 2-D hexagonally ordered cylindrical pores is superior to that in wormlike pores due to the smoothness of the channels in the former. External mass transfer and intraparticle diffusion both play roles in the adsorption process.

Download Full-text

FeYO3@rGO nanocomposites: Synthesis, characterization and application in photooxidative degradation of atrazine under visible light

Materials Express ◽

10.1166/mex.2021.1957 ◽

2021 ◽

Vol 11 (5) ◽

pp. 706-716

Author(s):

Nada D. Al-Khthami ◽

Tariq Altalhi ◽

Mohammed Alsawat ◽

Mohamed S. Amin ◽

Yousef G. Alghamdi ◽

...

Keyword(s):

Visible Light ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Bandgap Energy ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Structural Surface ◽

Adsorption Desorption

Different organic pollutants have been remediated photo catalytically by applying perovskite photocatalysts. Atrazine (ATR) is a pesticide commonly detected as a pollutant in drinking, surface and ground water. Herein, FeYO3@rGO heterojunction was synthesized and applied for photooxidation decomposition of ATR. First, FeYO 3nanoparticles (NPs) were prepared via routine sol-gel. After that, FeYO3 NPs were successfully incorporated with different percentages (5, 10, 15 and 20 wt.%) of reduced graphene oxide (rGO) in the synthesis of novel FeYO3@rGO photocatalyst. Morphological, structural, surface, optoelectrical and optical characteristics of constructed materials were identified via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM), adsorption/desorption isotherms, diffusive reflectance (DR) spectra, and photoluminescence response (PL). Furthermore, photocatalytic achievement of the constructed materials was evaluated via photooxidative degradation of ATR. Various investigations affirmed the usefulness of rGO incorporation on the advancement of formed photocatalysts. Actually, novel nanocomposite containing rGO (15 wt.%) possessed diminished bandgap energy, as well as magnified visible light absorption. Furthermore, such nanocomposite presented exceptional photocatalytic achievement when exposed to visible light as ATR was perfectly photooxidized over finite amount (1.6 g · L-1) from the optimized photocatalyst when illuminated for 30 min. The advanced photocatalytic performance of constructed heterojunctions could be accredited mainly to depressed recombination amid induced charges. The constructed FeYO3@rGO nanocomposite is labelled as efficient photocatalyst for remediation of herbicides from aquatic environments.

Download Full-text

Hydrothermal Synthesis of Iodine-Doped Nanoplates with Enhanced Visible and Ultraviolet-Induced Photocatalytic Activities

International Journal of Photoenergy ◽

10.1155/2012/915386 ◽

2012 ◽

Vol 2012 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Jiang Zhang ◽

Zheng-Hong Huang ◽

Yong Xu ◽

Feiyu Kang

Keyword(s):

Photocatalytic Activity ◽

Photoelectron Spectroscopy ◽

Oxygen Vacancies ◽

Diffuse Reflectance Spectroscopy ◽

Synergetic Effect ◽

X Ray Diffraction ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Photocatalytic Activities

The iodine-doped Bi2WO6(I-BWO) photocatalyst was prepared via a hydrothermal method using potassium iodide as the source of iodine. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. The photocatalytic activity of I-BWO for the degradation of rhodamine B (RhB) was higher than that of pure BWO and I2-BWO regardless of visible light (>420 nm) or ultraviolet light (<400 nm) irradiation. The results of DRS analysis showed that the I-BWO and I2-BWO catalysts had narrower band gaps. XPS analysis proved that the multivalent iodine species including I0and were coadsorbed on the defect surface of Bi2WO6in I-BWO. The enhanced PL intensity revealed that a large number of defects of oxygen vacancies were formed by the doping of iodine. The enhanced photocatalytic activity of I-BWO for degradation of RhB was caused by the synergetic effect of a small crystalline size, a narrow band gap, and plenty of oxygen vacancies.

Download Full-text

Silver Orthophosphate Immobilized on Flaky Layered Double Hydroxides as the Visible-Light-Driven Photocatalysts

International Journal of Photoenergy ◽

10.1155/2012/263254 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 20

Author(s):

Xianlu Cui ◽

Yaogang Li ◽

Qinghong Zhang ◽

Hongzhi Wang

Keyword(s):

Visible Light ◽

Diffuse Reflectance Spectroscopy ◽

Diffraction Field ◽

X Ray Diffraction ◽

Transmission Electron ◽

Photocatalytic Activities ◽

Visible Light Driven ◽

Double Hydroxide ◽

Double Hydroxides ◽

Acid Red G

Flaky layered double hydroxide (FLDH) was prepared by the reconstruction of its oxide in alkali solution. The composites with FLDH/Ag3PO4mass ratios at 1.6 : 1 and 3 : 1 were fabricated by the coprecipitation method. The powders were characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscope, and UV-vis diffuse reflectance spectroscopy. The results indicated that the well-distributed Ag3PO4in a fine crystallite size was formed on the surface of FLDH. The photocatalytic activities of the Ag3PO4immobilized on FLDH were significantly enhanced for the degradation of acid red G under visible light irradiation compared to bare Ag3PO4. The composite with the FLDH/Ag3PO4mass ratio of 3 : 1 showed a higher photocatalytic efficiency.

Download Full-text