scholarly journals Ultrasound-Assisted Rapid ZIF-8 Synthesis, Porous ZnO Preparation by Heating ZIF-8, and Their Photocatalytic Activity

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Pham Dinh Du ◽  
Nguyen Trung Hieu ◽  
Tran Vinh Thien
Keyword(s):  
Photocatalytic Activity ◽  
Room Temperature ◽  
Diffuse Reflectance ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Zeolitic Imidazolate Framework ◽  
X Ray ◽  
Photocatalytic Activities ◽  
Ft Ir ◽  
Adsorption Desorption

Zeolitic imidazolate framework-8 (ZIF-8) is synthesized quickly at room temperature in methanol with the support of ultrasound. Porous ZnO is also prepared via the thermal treatment of ZIF-8. The photocatalytic activities of the obtained materials are demonstrated via methylene blue (MB) decomposition under UV radiation. The obtained materials are characterized by means of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), nitrogen adsorption/desorption isotherms, UV-Vis diffuse reflectance spectra (DR-UV-Vis), and photoluminescence spectra. The results indicate that ZIF-8 and the materials obtained from ZIF-8 by heating in the air have photocatalytic activity under UV irradiation. The ZnO sample obtained by ZIF-8 calcination at 660°C for 5 h has the highest photocatalytic activity. However, the MB degradation photocatalytic efficiency of the ZnO samples is even lower than that of the ZIF-8 samples, indicating that ZIF-8 is an effective photocatalyst in the treatment of environmental pollution.

scholarly journals Pyrolysis Synthesized g-C3N4for Photocatalytic Degradation of Methylene Blue

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Gang Xin ◽  
Yali Meng
Keyword(s):  
Methylene Blue ◽  
Fourier Transform ◽  
Photocatalytic Activity ◽  
Carbon Nitride ◽  
Diffuse Reflectance ◽  
Photogenerated Electron ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Uv Visible

Graphitic carbon nitride (g-C3N4) was synthesized at 520°C by the pyrolysis of cyanamide, dicyandiamide, and melamine. The samples were characterized by X–ray diffraction (XRD), UV-visible diffuse reflectance spectra, Fourier transform infrared spectroscopy (FT-IR), and elemental analyzer. The photocatalytic activity of g-C3N4was evaluated by the photodegrading experiments of methylene blue (MB). The results indicated that g-C3N4. A photocatalytic mechanism presumed the MB photodegradation over the C3N4photocatalyst is attributed to photogenerated electron impelled multistep reduction of O2.

TiO2 Hollow Spheres Obtained under Autogenic Pressure at Elevated Temperature

2009 ◽  
Vol 79-82 ◽  
pp. 525-528 ◽  
Author(s):  
Ke Xun Li ◽  
Hong Liang Li ◽  
Jun Hua Zhao ◽  
Ying Chun Zhu ◽  
Xiu Song Zhao
Keyword(s):  
Elevated Temperature ◽  
Diffuse Reflectance ◽  
Hollow Spheres ◽  
Nitrogen Adsorption ◽  
Bet Surface Area ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surfactant Additive ◽  
Tio2 Hollow Spheres ◽  
Adsorption Desorption

Carbon/TiO2 composites were prepared via the reaction under Autogenic Pressure at Elevated Temperature (RAPET) using alkoxides as precursor, and then porous TiO2 hollow spheres were derived after removing the carbon ingredient by calcination at 600°C. The influence of surfactant additives, including the addition ratio and the nature of the surfactants, on the morphology and the structures of the Carbon/TiO2 composites and the derived TiO2 were also studied with scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-Vis diffuse reflectance spectrophotoscopy (DRS) and nitrogen adsorption-desorption measurements. The results revealed that the morphology of the products turned to spherical and then fusiform and the structures turned from hollow to solid with the increasing of surfactant additive. The BET surface area of the hollow TiO2 was modified from 12m2/g to 57m2/g after calcinations. The XRD investigation indicates that the phases of the TiO2 in both the carbon/TiO2 composites and the derived TiO2 hollow spheres are anatase.

scholarly journals Impedimetric Detection of Ammonia and Low Molecular Weight Amines in the Gas Phase with Covalent Organic Frameworks

Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1385 ◽  
Author(s):  
Andrés Rodríguez ◽  
Elio Rico ◽  
Cesar Sierra ◽  
Oscar Rodríguez
Keyword(s):  
Molecular Weight ◽  
Room Temperature ◽  
Nitrogen Adsorption ◽  
Low Molecular Weight ◽  
Covalent Organic Frameworks ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Nitrogen Adsorption Isotherms ◽  
Significant Interference

Two Covalent Organic Frameworks (COF), named TFP-BZ and TFP-DMBZ, were synthesized using the imine condensation between 1,3,5-triformylphloroglucinol (TFP) with benzidine (BZ) or 3,3-dimethylbenzidine (DMBZ). These materials were deposited, such as films over interdigitated electrodes (IDE), by chemical bath deposition, giving rise to TFP-BZ-IDE and TFP-DMBZ-IDE systems. The synthesized COFs powders were characterized by Powder X-Ray Diffraction (PXRD), Fourier Transform Infrared spectroscopy (FT-IR), solid-state Nuclear Magnetic Resonance (ssNMR), nitrogen adsorption isotherms, Scanning Electron Microscopy (SEM), and Raman spectroscopy, while the films were characterized by SEM and Raman. Ammonia and low molecular weight amine sensing were developed with the COF film systems using the impedance electrochemical spectroscopy (EIS). Results showed that the systems TFP-BZ-IDE and TFP-DMBZ-IDE detect low molecular weight amines selectively by impedimetric analysis. Remarkably, with no significant interference by other atmospheric gas compounds such as nitrogen, carbon dioxide, and methane. Additionally, both COF films presented a range of sensitivity at low amine concentrations below two ppm at room temperature.

Preparation of Fe3O4/TiO2 magnetic mesoporous composites for photocatalytic degradation of organic pollutants

2017 ◽  
Vol 75 (7) ◽  
pp. 1523-1528 ◽  
Author(s):  
Hongfeng Zhang ◽  
Xiu He ◽  
Weiwei Zhao ◽  
Yu Peng ◽  
Donglan Sun ◽  
...  
Keyword(s):  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Sol Gel ◽  
Nitrogen Adsorption ◽  
Magnetic Composite ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mesoporous Composites ◽  
Uv Lamp ◽  
Adsorption Desorption

Fe3O4/TiO2 magnetic mesoporous composites were synthesized through a sol-gel method with tetra-n-butyl titanate as precursor and surfactant P123 as template. The as-prepared Fe3O4/TiO2 composites were characterized by X-ray diffraction, diffuse reflectance spectroscopy, nitrogen adsorption-desorption isotherm and pore size distribution. The as-synthesized products were applied as photocatalysis for the degradation of Acid Black ATT and tannery wastewater under UV lamp irradiation. Fe3O4/TiO2-8 composites containing Fe3O4 of 8 wt% were selected as model catalysts. The optimal catalyst dosage was 3 g/L in this photocalytic system. The magnetic Fe3O4/TiO2 composites possessed good photocatalytic stability and durability. This approach may provide a platform to prepare a magnetic composite to optimize the catalytic ability.

Preparation and Luminescence of Host-Guest (SBA-15)-(Arsenano-III) Nanocomposite Materials

2013 ◽  
Vol 785-786 ◽  
pp. 537-541
Author(s):  
Xiao Dong Li
Keyword(s):  
Low Temperature ◽  
Absorption Spectra ◽  
Molecular Sieves ◽  
Diffuse Reflectance ◽  
Nitrogen Adsorption ◽  
Nanocomposite Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Prepared Composite ◽  
Adsorption Desorption

The nanosized channels of SBA-15 molecular sieves were used as template and arsenano-III (ASA-III) was trapped inside the SBA-15 molecular sieves by means of liquid grafting method. The prepared nanocomposite materials were characterized by the powder X-ray diffraction, low temperature nitrogen adsorption-desorption and solid diffuse reflectance absorption spectra. The powder X-ray diffraction indicated the structure of the (SBA-15)-(ASA-III) still remains two-dimensional hexagonal mesostructrure. The low temperature nitrogen adsorption-desorption research showed that the ASA-III was present on the inner surface and partially occupied the channels of the molecular sieve. The UV-Vis solid state diffuse reflectance absorption spectra of the prepared composite materials showed the steroconfinmment effect of the host SBA-15 channels on the guest ASA-III and the guest was in the channels of the SBA-15 host. Luminous spectra showed that the prepared (SBA-15)-(ASA-III) nanocomposite materials have the investigating optical properties.

Preparation and Photocatalytic Study of Nano Cadmium Sulphide

2012 ◽  
Vol 584 ◽  
pp. 406-410 ◽  
Author(s):  
S. Ershadul Haque ◽  
B. Ramdas ◽  
A. Sheela
Keyword(s):  
Photocatalytic Activity ◽  
Room Temperature ◽  
Diffuse Reflectance ◽  
Uv Light ◽  
Cadmium Sulphide ◽  
Spectroscopic Techniques ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
Sunlight Irradiation ◽  
X Ray

Nano CdS has been prepared by solid state method at room temperature in the absence of any surfactants or dopants. It is characterized by powder X-ray diffraction, scanning electron microscopy (SEM) and diffuse reflectance spectroscopic techniques. It shows cubic structure with the particle size ranging about 20nm. It also exhibits a strong photocatalytic activity for the decomposition of methyl orange (MO) and rhodamine B (RB) under UV and sunlight irradiation. The result shows that CdS exerts greater photocatalytic activity for MO (83%) and RB (73%) under sunlight than UV light.

Synthesis and characterization of polypyrrole/molybdenum oxide composite for ammonia vapour sensing at room temperature

2021 ◽  
pp. 096739112110365
Author(s):  
Mohd Urooj Shariq ◽  
Ahmad Husain ◽  
Mahfoozurrahman Khan ◽  
Anees Ahmad
Keyword(s):  
Electron Microscopy ◽  
Molybdenum Oxide ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Oxide Composite ◽  
Ammonia Vapour ◽  
Ft Ir ◽  
Adsorption Desorption

In this study, polypyrrole (PPy) and polypyrrole/molybdenum oxide composite (PPy/MoO3) were synthesized by the chemical oxidative method in an aqueous medium, using anhydrous ferric chloride (FeCl3) as an oxidant. The successful preparation of materials was confirmed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmittance electron microscopy (TEM). PPy and PPy/MoO3 were converted into pellets which were used as the sensor. A four-in-line probe device was used for studying DC electrical conductivity–based ammonia vapour–sensing properties at three different ammonia concentrations, that is, 1 M, 0.5 M and 0.1 M. The PPy/MoO3 sensor showed much-improved sensing performance than the PPy sensor in terms of % sensing response and reversibility. PPy/MoO3 sensor showed excellent selectivity for ammonia vapours against various VOCs. The % sensing response of PPy/MoO3 sensor towards ammonia was found to be 2.19, 2.50, 3.16, 3.87, 4.1, 5.15, 6.19, 6.55 and 7.77 times greater than ethanol, methanol, acetone, acetaldehyde, formaldehyde, toluene, benzene, chloroform and n-hexane, respectively. In the end, a sensing mechanism was also proposed, which is based on rapid adsorption–desorption of ammonia molecules on the PPy/MoO3 sensor’s surface.

SBA-15(P)-Supported Tetraethylenepentamine for CO2 Capture

2012 ◽  
Vol 457-458 ◽  
pp. 1283-1286 ◽  
Author(s):  
Yong Hong Yang ◽  
Cheng Yang ◽  
Jin Hu Wu
Keyword(s):  
Nitrogen Adsorption ◽  
Temperature Programmed Desorption ◽  
X Ray Diffraction ◽  
Impregnation Process ◽  
X Ray ◽  
Adsorption Capacities ◽  
Ft Ir ◽  
Temperature Programmed ◽  
Loading Amount ◽  
Adsorption Desorption

In this paper, various amine-modified CO2 adsorbents were prepared by incorporating tetraethylenepenthamine (TEPA) onto SBA-15(P) by controlling dynamic impregnation process. The materials were characterized by X-ray diffraction (XRD), nitrogen adsorption/desorption, elemental analysis (EA) and Fourier transform infrared (FT-IR) experiments. Moreover, the adsorption capacities and cycle life were evaculated by CO2 temperature programmed desorption (CO2-TPD). Various characterization results indicate that the morphology and loading amount of TEPA on the support material were controlled by adjusting dynamic impregnation times. Under given conditions, there is an optimum dynamic impregnation times.

scholarly journals Synthesis, Characterization, and Photocatalytic Activity of Microspheres Functionalized with Porphyrin

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Jin-Hua Cai ◽  
Jin-Wang Huang ◽  
Han-Cheng Yu ◽  
Liang-Nian Ji
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Reflectance Spectroscopy ◽  
Model Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir

In order to utilize visible light more efficiently in the photocatalytic reaction, microspheres sensitized by 5-(4-allyloxy)phenyl-10,15,20-tri(4-methylphenyl)porphyrin (APTMPP) were prepared and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), nitrogen physisorption, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and UV-vis diffuse reflectance spectroscopy, and so forth, The characterization results indicated that APTMPP-MPS- was composed of the anatase crystal phase. The morphology of the composite materials was spheriform with size of 0.3–0.7 μm and the porphyrin was chemisorbed on the surface of through a Si–O–Ti bond. The photooxidation ofα-terpinene was employed as the model reaction to evaluate the photocatalytic activity of APTMPP-MPS- microspheres under visible light. The results indicated that the photodegradation ofα-terpinene was significantly enhanced in the presence of the APTMPP-MPS- compared with the nonmodified under visible light.

scholarly journals Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 558
Author(s):  
Wenhui Zhu ◽  
Caiyun Zhang ◽  
Yali Chen ◽  
Qiliang Deng
Keyword(s):  
Methylene Blue ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Degradation Rate ◽  
Model Compound ◽  
Vibrating Sample Magnetometer ◽  
Simulated Sunlight ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

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