Carbon Nanotube Templated Growth of Nano-Crystallinity ZSM-5

2011 ◽  
Vol 299-300 ◽  
pp. 1020-1023 ◽  
Author(s):  
Ke Tang ◽  
Xin Hong

MFI-type(ZSM-5) zeolite nanocrystals with SiO2/Al2O3ratios of 100 has been synthesized through crystallization of gel in mesoporous system of carbon nanotubes(CNTS) with internal diameter of 20~30nm. Investigation by using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), transmission electron microscope (TEM) and scanning electron microscope (SEM) shows that the nanocrystals possess the typical nanosized zeolites structural characteristics which is different from those of microsized zeolites. Compared with those of the corresponding sample synthesized in hydrothermal system, the bands of the nanosized sample are shifted slightly to lower or higher wavenumbers. The TEM images of the purified carbon nanotubes and nanosized ZSM-5 crystals after the removal of the carbon matrix suggest that clean and homogeneous carbon nanotubes have internal diameters of approximately 20~30 nm and the most crystal sizes are in the range 30~60nm. The SEM photograph verifies the existing of nanosized ZSM-5.

2011 ◽  
Vol 194-196 ◽  
pp. 594-597
Author(s):  
Ke Tang ◽  
Xin Hong ◽  
Jin Gang Qi

FAU-type(NaY) zeolites nanocrystals have been synthesized through crystallization of gel in mesoporous system of carbon nanotubes(CNTS) with a internal diameter of 20~30 nm. Investigation by using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), transmission electron microscope (TEM) shows that the nanocrystals possess the typical nanosized zeolites structural characteristics which is different from those of microsized zeolites.


Author(s):  
Nkosinathi Goodman Dlamini ◽  
Albertus Kotze Basson ◽  
Viswanadha Srirama Rajasekhar Pullabhotla

Nanotechnology offers a great opportunity for efficient removal of pollutants and pathogenic microorganisms in water. Copper nanoparticles were synthesized using a polysaccharide bioflocculant and its flocculation, removal efficiency, and antimicrobial properties were evaluated. The synthesized nanoparticles were characterized using thermogravimetry, UV-Visible spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction, scanning electron microscope (SEM), and transmission electron microscope (TEM). The highest flocculation activity (FA) was achieved with the lowest concentration of copper nanoparticles (0.2 mg/mL) with 96% (FA) and the least flocculation activity was 80% at 1 mg/mL. The copper nanoparticles (CuNPs) work well without the addition of the cation as the flocculation activity was 96% and worked best at weak acidic, neutral, and alkaline pH with the optimal FA of 96% at pH 7. Furthermore, the nanoparticles were found to be thermostable with 91% FA at 100 °C. The synthesized copper nanoparticles are also high in removal efficiency of staining dyes, such as safranin (92%), carbol fuchsine (94%), malachite green (97%), and methylene blue (85%). The high removal efficiency of nutrients such as phosphate and total nitrogen in both domestic wastewater and Mzingazi river water was observed. In comparison to ciprofloxacin, CuNPs revealed some remarkable properties as they are able to kill both the Gram-positive and Gram-negative microorganisms.


2011 ◽  
Vol 194-196 ◽  
pp. 442-445
Author(s):  
Cai Liu Yin ◽  
Guo Fu Wen ◽  
Qi Zhong Huang ◽  
Xiu Fei Wang

Carbon nanotubes(CNTs) with uniform wall thickness were synthesized by a solid-liquid reaction route. Calcium carbide block and carbon tetrachloride as double carbon sources were enclosed in a 100ml stainless steel autoclave at 400°C for 8 hours. The fabricated products were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), and Transmission electron microscope (TEM). The research results indicate that the synthesized CNTs have lengths on the order of 10μm and external diameters in the range of 120-200nm. The nanotubes are typically the uniform inner diameters of 70nm and grow in the same direction. The growth mechanism is simply discussed.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Tiedan Chen ◽  
Yanqiu Xia ◽  
Zhengfeng Jia ◽  
Zhilu Liu ◽  
Haobo Zhang

Graphene oxide (GO) nanosheets were prepared by modified Hummers and Offeman methods. Furthermore, oleic acid (OA) capped graphene oxide (OACGO) nanosheets were prepared and characterized by means of Fourier transform-infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and X-ray diffraction (XRD). At the same time, the friction and wear properties of OA capped graphite powder (OACG), OACGO, and oleic acid capped precipitate of graphite (OACPG) as additives in poly-alpha-olefin (PAO) were compared using four-ball tester and SRV-1 reciprocating ball-on-disc friction and wear tester. By the addition of OACGO to PAO, the antiwear ability was improved and the friction coefficient was decreased. Also, the tribological mechanism of the GO was investigated.


2011 ◽  
Vol 175-176 ◽  
pp. 341-344 ◽  
Author(s):  
Byoung Suhk Kim ◽  
Kyu Oh Kim ◽  
Ick Soo Kim

We report the electrospun poly(L-lactide) (PLA) nanofibers incorporating polyhedral oligosilsesquioxane (POSS)-modified multiwalled carbon nanotubes (MWNTs). FT-IR, transmission electron microscopy (TEM) and Raman analysis confirmed the existence of POSS macromers bonded to the MWNTs as an extra phase. The thermal and microstructure properties of the PLA hybrid nanofibers with POSS-modified MWNTs were investigated by thermogravimetric analysis (TGA) and Wide-angle X-ray diffraction (WAXD).


2013 ◽  
Vol 734-737 ◽  
pp. 2528-2531
Author(s):  
Yu Mei Gong ◽  
Qing Liang ◽  
Jing Guo ◽  
Hong Zhang ◽  
Fu Cheng Guan

Anatase/brookite mixtured TiO2nanoparticles have been synthesized by using a two-step process through a chimie douce technique. The as-prepared powders were characterized by Fourier transform infrared (FT-IR) spectra, X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and a nitrogen adsorption apparatus in multipoint Brunauer-Emmett-Teller (BET) method. The results indicated that the TiO2nanoparticles were composed of biphasial anatase/brookite mixtures, 38% anatase phase formed in quasi-spherical shape and 62% brookite phase formed in nanorod shape. The specific surface area, the average pore diameter, and the specific pore volume were 100.06 m2/g, 14.0 nm, and 0.561 cm3/g, respectively.


2021 ◽  
Vol 11 (12) ◽  
pp. 5630
Author(s):  
Norah Salem Alsaiari ◽  
Fatimah Mohammed Alzahrani ◽  
Khadijah Mohammedsaleh Katubi ◽  
Abdelfattah Amari ◽  
Faouzi Ben Rebah ◽  
...  

The removal of heavy metals from water has become a global environmental problem. Various materials have been applied as adsorbent to remove metals from water. In this field, nanomaterials have been gaining increasing interest due to their exceptional properties. In this work, we discuss the synthesis of a core-shell structure nanocomposite by the modification of magnetic chitosan (CS) (Fe3O4/CS) with polyethylenimine (PEI) to produce Fe3O4/CS/PEI composite for the adsorption of arsenic ions (As(V) and As(III)) from aqueous solution. The synthesized materials were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscope (TEM), and vibrating sample magnetometer (VSM). The results indicated the successful combination of three components of the nanocomposite. The adsorption conditions were optimized by studying the effect of different parameters included pH, contact time, initial concentration, and adsorbent dosage. The optimum adsorption pH was found to be 6.7 while the optimum adsorbent dosage was found to be 2.0 and 1.5 g/L for As(III) and As(V), respectively. The removal efficiency for the uptake of As(III) and As(V) ions over Fe3O4/CS/PEI nanocomposite at optimum conditions was found to be 99.5 and 99.7%, respectively. The experimental results were fitted using Freundlich’s and Langmuir’s isotherms. The data were more fitted to Langmuir isotherm providing a suggestion of monolayer adsorption with maximum adsorption capacity equal to 77.61 and 86.50 mg/g for the removal of As(III) and As(V), respectively. Moreover, linear regression coefficient (R2) indicated that the adsorption of arsenic ions over the synthesized magnetic nanocomposite obeyed pseudo 2nd order suggesting the chemisorption process. The reusability of the nanosorbent for arsenic uptake using sodium hydroxide as eluent was also assessed up to five cycles. Interestingly, Fe3O4/CS/PEI nanocomposite can be considered as a promising adsorbent for As ions’ removal from water and should be tested for the removal of other pollutants.


2017 ◽  
Vol 730 ◽  
pp. 37-41 ◽  
Author(s):  
Hui Li Cao ◽  
Yuan Chang Shi ◽  
Hao Shen ◽  
Hu Dong Zhan ◽  
Jiu Rong Liu

In this paper carboxylated carbon nanotubes/polypyrrole composite (CNTs/PPy) was synthesized in different surfactants aqueous under sonication. Carboxylated CNTs was synthesized in hydrogen nitrate by ultrasonic method and coated by PPy. The synthesized CNTs/PPy in different surfactants was evaluated by Fourier transform infrared spectrometer (FT-IR) and transmission electron microscope. The FT-IR patterns illustrate that CNTs were successfully doped by PPy. The morphology of CNTs/PPy synthesized showed on the transmission electron microscope images. The composite materials sythesized without surfactant are easy reunited. It is also found the surface of CNTs/PPy synthesized in cetyl trimethyl ammonium bromide (CTAB) is smoother than that in other surfactants. The coating effect is better with thicker coating layer. The higher magnification of HRTEM images show the PPy was deposited directly on the surface of carbon nanotubes. The final products are the ordered coaxial composite with well-defined core-shell structure.


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Kun Liu ◽  
Lianjie Zhu ◽  
Tengfei Jiang ◽  
Youguang Sun ◽  
Hongbin Li ◽  
...  

Mesoporous anatase TiO2micro-nanometer composite structure was synthesized by solvothermal method at 180°C, followed by calcination at 400°C for 2 h. The as-prepared TiO2was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and Fourier transform infrared spectrum (FT-IR). The specific surface area and pore size distribution were obtained from N2adsorption-desorption isotherm, and the optoelectric property of the mesoporous TiO2was studied by UV-Vis absorption spectrum and surface photovoltage spectra (SPS). The photocatalytic activity was evaluated by photodegradation of sole rhodamine B (RhB) and sole phenol aqueous solutions under simulated sunlight irradiation and compared with that of Degussa P-25 (P25) under the same conditions. The photodegradation preference of this mesoporous TiO2was also investigated for an RhB-phenol mixed solution. The results show that the TiO2composite structure consists of microspheres (∼0.5–2 μm in diameter) and irregular aggregates (several hundred nanometers) with rough surfaces and the average primary particle size is 10.2 nm. The photodegradation activities of this mesoporous TiO2on both RhB and phenol solutions are higher than those of P25. Moreover, this as-prepared TiO2exhibits photodegradation preference on RhB in the RhB-phenol mixture solution.


2014 ◽  
Vol 13 (03) ◽  
pp. 1450018 ◽  
Author(s):  
S. K. Kannan ◽  
M. Sundrarajan

In this study, the synthesis of a cerium oxide nanoparticle was carried out from Acalypha indica leaf extract. The synthesized nanoparticle was characterized by using X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX) and Transmission Electron Microscope (TEM) for structural confirmation. The studies clearly indicate that the synthesized CeO 2 nanoparticle is a crystalline material with particle size between 25–30 nm. Further analysis was carried out by Fourier Transform infrared spectroscopy (FT-IR), to provide evidence for the presence of Ce - O - Ce asymmetry stretching of the CeO 2 nanoparticle. Thermo Gravimetric and Differential Scanning Calorimetry analyses gave the thermal properties of cerium oxide nanoparticles. Antibacterial studies were conducted using the synthesized CeO 2. This result showed increasing rate of antibacterial behavior with gram positive and gram negative bacteria.


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