scholarly journals Preparation and Carbonization of Glucose and Pyromellitic Dianhydride Crosslinked Polymers

2021 ◽  
Vol 7 (3) ◽  
pp. 56
Author(s):  
Fabrizio Caldera ◽  
Antonella Moramarco ◽  
Federico Cesano ◽  
Anastasia Anceschi ◽  
Alessandro Damin ◽  
...  
Keyword(s):  
Organic Contaminants ◽  
Gas Flow ◽  
High Surface ◽  
High Surface Area ◽  
Pyromellitic Dianhydride ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Porous Texture ◽  
Molar Ratios ◽  
Transmission Electron

In this work, four types of nanosponges were prepared from pyromellitic dianhydride (PMDA) and D-glucose (GLU) with different molar ratios (1.5:1, 2:1, 2.5:1 and 3:1). The obtained PMDA/GLU nanosponges were then pyrolyzed at 800 °C for 30 min under N2 gas flow. The prepared polymeric nanosponges were investigated by FTIR spectroscopy, elemental and thermogravimetric analyses to unravel the role played by the different molar ratio of the precursors in the formation of the polymer. The pyrolyzed nanosponges were investigated by means of porosity measurements, X-ray diffraction analysis, Raman spectroscopy and high-resolution transmission electron microscopy. Notably, no significant correlation of the amounts of used precursors with the porous texture and structure was evidenced. The results corroborate that PMDA and GLU can be easily combined to prepare nanosponges and that the carbon materials produced by their pyrolysis can be associated with glassy carbons with a microporous texture and relatively high surface area. Such hard carbons can be easily obtained and shrewdly used to segregate relatively small molecules and organic contaminants; in this study methylene blue adsorption was investigated.

Synthesis of Nanoporous Materials Al-MCM-41 from Natural Halloysite

NANO ◽  
2015 ◽  
Vol 10 (01) ◽  
pp. 1550005 ◽  
Author(s):  
Yaling Xie ◽  
Aidong Tang ◽  
Huaming Yang
Keyword(s):  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Halloysite Nanotubes ◽  
Nanoporous Materials ◽  
Molar Ratio ◽  
Molar Ratios ◽  
Naoh Solution ◽  
The One ◽  
Mcm 41

Nanoporous materials Al -MCM-41 with varying Si / Al molar ratios have been successfully synthesized from natural clay mineral halloysite nanotubes (HNTs). Hydrothermal treatment of acid-pretreated HNTs and NaOH solution resulted in the one-step synthesis of final nanoporous products by using surfactant. The effects of Si / Al molar ratios (7.7, 61.0 and 176.5) on the surface area, porosity and degree of structural order of Al -MCM-41 materials have been investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), N 2 adsorption–desorption measurements and Fourier transform infrared (FTIR) spectra techniques. The results indicated that Si / Al molar ratio had important effect on the characteristics of nanoporous materials, and Al -MCM-41 with an intermediate Si / Al molar ratio of 61.0 exhibited excellent characteristics with high degree of order, high surface area (S BET ) of 1033 m2/g and pore volume of 0.92 mL/g.

scholarly journals Synthesis and Characterization of Hierarchical Porousα-FeOOH for the Adsorption and Photodegradation of Rhodamine B

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Jianliang Cao ◽  
Gaojie Li ◽  
Yan Wang ◽  
Guang Sun ◽  
Hari Bala ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Rhodamine B ◽  
Uv Light ◽  
Low Cost ◽  
High Surface ◽  
High Surface Area ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Hierarchical Porous ◽  
Templated Method

Hierarchical porousα-FeOOH nanoparticles were controlled and prepared via a facile polystyrene (PS) microspheres-templated method. Theα-Fe2O3was obtained by the calcination of the as-preparedα-FeOOH. The resulting nanoparticles were characterized by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N2-sorption techniques. The adsorption and photodegradation of Rhodamine B performance were evaluated under UV light at room temperature. The results indicated that the photocatalytic activity of theα-FeOOH nanoparticles is superior toα-Fe2O3-200 andα-Fe2O3-300 due to the hierarchically multiporous structure and high surface area. This convenient and low-cost process provides a rational synthesis alternative for the preparation of multiporous materials and the as-synthesis products have great foreground applications in many aspects.

scholarly journals Liquid petroleum gas sensing performance enhanced by CuO modification of nanocrystalline ZnO-TiO2

2016 ◽  
Vol 34 (3) ◽  
pp. 571-581
Author(s):  
R.B. Pedhekar ◽  
F.C. Raghuwanshi ◽  
V.D. Kapse
Keyword(s):  
Thick Film ◽  
Gas Sensing ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Transmission Electron ◽  
Liquid Petroleum Gas ◽  
Synthesized Materials ◽  
Sensing Characteristics

AbstractNanocrystalline ZnO-TiO2 (with molar ratios 9:1, 7:3, 1:1, 3:7 and 1:9) were successfully synthesized by hydrothermal method. Synthesized materials were examined with the help of X-ray diffraction and transmission electron microscope. Liquid petroleum gas sensing characteristics of the ZnO-TiO2 films were investigated at different operating temperatures. The ZnO-TiO2 thick film (with 1:1 molar ratio) exhibited good response toward liquid petroleum gas as compared to other investigated compositions. Further, liquid petroleum gas sensing characteristics of CuO modified ZnO-TiO2 thick films were investigated. 0.2 M CuO modified ZnO-TiO2 thick film exhibited excellent liquid petroleum gas sensing characteristics such as higher response (~ 1637.49 at 185 °C) with quick response time (~30 s), low recovery time (~70 s), excellent repeatability and stability at low operating temperature.

Nanostructured Ni/CeO2–ZrO2 Catalysts for CO2 Conversion into Synthetic Natural Gas

2019 ◽  
Vol 19 (6) ◽  
pp. 3269-3276 ◽  
Author(s):  
Luciano Atzori ◽  
Elisabetta Rombi ◽  
Daniela Meloni ◽  
Roberto Monaci ◽  
Maria Franca Sini ◽  
...  
Keyword(s):  
Mixed Oxides ◽  
High Surface ◽  
High Surface Area ◽  
Xrd Analysis ◽  
Molar Ratio ◽  
Soft Template ◽  
Synthetic Natural Gas ◽  
Molar Ratios ◽  
Mild Reduction ◽  
Average Size

NiO–CeO2–ZrO2 mixed oxides, with Ni/(Ce + Zr) = 1 mol/mol and different Ce/Zr molar ratios, were prepared by the soft-template method. The chemical composition, texture, structure, and redox features of the synthesized systems were investigated by different techniques. All samples were nanocrystalline (NiO nanocrystal average size 4 nm) and had high surface area and quite an ordered mesoporous system. The catalytic performances in the CO2 conversion into methane were studied at atmospheric pressure, 300 °C, and stoichiometric H2/CO2 molar ratio. Prior to reaction the catalysts were submitted to a mild reduction pretreatment (H2 at 400 °C for 1 h). XRD analysis of the samples after pretreatment showed the presence of small Ni crystals (4–7 nm) on all the samples as well as of some unreduced NiO nanocrystals on the systems with high Zr content, in accordance with H2-TPR experiments, which indicated that NiO reduction is promoted by CeO2 but hindered by ZrO2. The catalytic tests were performed at two different space velocities (72000 and 900000 cm3 h−1 g−1cat) on a series of Ni-based catalysts supported on CeO2–ZrO2 systems with different Ce/Zr ratios, including the two pure oxides. CO2 conversion and selectivity to CH4 (which was always close to 100 mol%) were constant throughout the 6-hour runs. CO2 conversion resulted to increase with CeO2 content in the catalyst, thus indicating the role of the CeO2 component of the support in activating CO2, whereas H2 is activated on the Ni nanoparticles.

Ni-doped, urchin-like Bi2S3 particles for electrocatalytic oxidation of glucose

2021 ◽  
pp. 2150006
Author(s):  
Biao Wang ◽  
Ya Liu ◽  
Xu Huai ◽  
Yuqing Miao
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Electrocatalytic Oxidation ◽  
High Surface ◽  
High Surface Area ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Capacitance Current ◽  
Oxidation Of Glucose

In order to develop non-noble metal-based electrocatalysts for glucose oxidation, the Ni-doped, urchin-like Bi2S3 particles were prepared by a solvothermal method using the solvent of ethylene glycol/H2O. The obtained products were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The background signal from capacitance current is relatively low and the electrocatalytic oxidation current of glucose relatively high due to the urchin-like nanostructure of Bi2S3 particles and high surface area where the presence of Bi also improves the electrocatalytic performance of NiII/NiIII shift.

Synthesis and Analysis of High Surface Area Vanadium Carbide Nanoparticles

2012 ◽  
Vol 585 ◽  
pp. 95-99 ◽  
Author(s):  
M. Mahajan ◽  
K. Singh ◽  
O.P. Pandey
Keyword(s):  
Surface Area ◽  
Vanadium Carbide ◽  
High Surface ◽  
High Surface Area ◽  
X Ray Diffraction ◽  
High Melting Point ◽  
X Ray ◽  
Transmission Electron ◽  
Product Powder ◽  
Scanning Electron

Vanadium carbide is known for its applications due to extreme hardness and high melting point. In this present work, vanadium carbide nanoparticles have been synthesized in a specially designed stainless steel autoclave by solvothermal route using vanadium pentoxide (V2O5) as precursor along with a hydrocarbon acetone (C3H6O) in the presence of reducing agent magnesium (Mg). The optimization of reaction time was studied at constant temperature of 800oC. The product powder was characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscope (TEM) and Brunauer – Emmett – Teller (BET) techniques. The results indicate that the product was vanadium carbide having particle size of about 30 nm with high surface area.

Synthesis and Characterization of ZrO2/Graphene Nanocomposite Materials

2012 ◽  
Vol 531 ◽  
pp. 161-164 ◽  
Author(s):  
Zong Hua Wang ◽  
Fu Qiang Zhu ◽  
Jan Fei Xia ◽  
Fei Fei Zhang ◽  
Yan Zhi Xia ◽  
...  
Keyword(s):  
High Surface ◽  
High Surface Area ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Simple Method ◽  
Transmission Electron ◽  
Ft Ir ◽  
Graphene Nanocomposite ◽  
Adsorption Desorption

Zirconia/graphene (ZrO2/graphene) nanocomposite has been successfully synthesized by a simple method. The as-prepared nanocomposite was characterized using transmission electron microscopy (TEM), FT-IR spectroscopy, power X-ray diffraction (XRD) and nitrogen adsorption-desorption. It was found that tetragonal ZrO2was uniformly deposited on graphene, which resulted in the formation of two-dimensional nanocomposite, it showed a high surface area of 165 m2/g.

Convenient Route to Cu-Ag Bimetallic Nanoleaflets with High Content of Cu and their Electrochemical Properties

2017 ◽  
Vol 727 ◽  
pp. 395-402
Author(s):  
Zi Run Wang ◽  
Xin Liu ◽  
Gui Qi Xie ◽  
Yi Wu ◽  
Ming Nie ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Reduction Method ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Phase Reduction ◽  
Transmission Electron ◽  
Convenient Route

Cu-Ag alloy nanoparticles were synthesized by a liquid phase reduction method. Using sodium formaldehyde sulfoxylate (SFS) as reducing agents, copper-silver bimetallic nanoleaflets with high content of Cu were prepared. The obtained Cu-Ag bimetallic nanocrystal were characterized by powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), field emission scanning electron microscope (FESEM), high resolution transmission electron microscopy (HRTEM) and transmission electron microscopy (TEM). Different molar ratio of Cu-Ag bimetallic nanomaterials could produce different morphologies. The surfactant β-CD plays a crucial role on the structure of the products. The different molar ratios of Cu-Ag were also investigated. The electrochemical activity was evaluated using cyclic voltammetry (CV), electrochemical hydrogen evolution reaction (HER) in a 0.5M Na2SO4 electrolyte.

scholarly journals Fabrikasi Nanotubes Titanium Dioksida (TiO2) Menggunakan Metode Hidrotermal

2017 ◽  
Vol 3 (1) ◽  
pp. 20-26
Author(s):  
Atik Setyani ◽  
Emas Agus Prastyo Wibowo
Keyword(s):  
Tio2 Nanoparticles ◽  
Tio2 Nanotubes ◽  
Crystal Size ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

Nanotubes received great attention because it has a high surface area. In this study, TiO2 nanotubes fabricated via hydrothermal method from  synthesis of TiO2 nanoparticles via sol-gel method. Catalysts that have been synthesized later in the characterization by X-Ray Diffraction (XRD) to obtain the crystal size and crystallinity. Crystal size of TiO2 nanoparticles at a temperature of 450C is 13.78 nm. Then characterized by Transmission Electron Microscopy (TEM) to look at the formation of nanotubes. Characterization of TiO2 nanotubes with TEM shows that the structure of the tubes had already been formed TNTs although the growth has not been perfect. It can be seen from the structure TNTs who tend to be short and yet so irregular.DOI: http://dx.doi.org/10.15408/jkv.v0i0.5036  

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