scholarly journals Characterization of Commercial TiO2 P90 Modified with ZnO by the Impregnation Method

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Tetiana А. Dontsova ◽  
Olena I. Yanushevska ◽  
Svitlana V. Nahirniak ◽  
Anastasiya S. Kutuzova ◽  
Grigory V. Krymets ◽  
...  

This article is devoted to TiO2/ZnO nanocomposites’ creation by modifying with the commercial TiO2/P90 product using the impregnation method and identifying the effect of the ZnO modifier on its adsorption, structural, photocatalytic, and electrical properties. The synthesized TiO2/ZnO nanocomposites were characterized by XRD, XRF, XPS, and low-temperature nitrogen adsorption-desorption methods. As a result, nanostructured TiO2/ZnO composites with the ZnO content of 2, 5, 10, and 15% were obtained. It was shown that the phase composition of TiO2/P90 does not change during the nanocomposite synthesis. XPS studies of TiO2/ZnO nanocomposites indicated the presence of Ti4+, Zn2+, O2−, and OH states on their surface, which is associated with TiO2, ZnO, and hydroxide ions. The nitrogen adsorption-desorption method showed that the commercial TiO2/P90 sample is nonporous, and all TiO2/ZnO nanocomposites are characterized by almost the same homogeneous mesoporous structure. Experimentally established sorption and photocatalytic properties depend on the specific surface area and electrostatic interaction with dyes. The effect of the ZnO modifier on I-V characteristics of the TiO2/P90 sample was revealed. The obtained experimental data showed that the TiO2/P90 sample contains one type of current carriers, and TiO2/2ZnO and TiO2/5ZnO nanocomposites are characterized by two types of current carriers.

2013 ◽  
Vol 22 (3) ◽  
pp. 096369351302200
Author(s):  
N. Ivashchenko ◽  
V. Tertykh ◽  
J. Skubiszewska-Zięba ◽  
R. Leboda ◽  
S. Khainakov ◽  
...  

Palladium nanoparticles with controlled size were synthesized within the pores of the mesoporous SBA-15 and SBA-16 silicas with grafted silicon hydride groups. Nitrogen adsorption-desorption method, X-ray diffraction and transmission electron microscopy (TEM) were used for characterization of palladium-containing composites. Results of material study clearly revealed that Pd nanoparticles prepared by this method were located inside the porous channels and were quite uniform in size (mostly 5–6 nm). The influence of metal content on the particles size and porous structure of supports was investigated.


2012 ◽  
Vol 9 (3) ◽  
pp. 1320-1326
Author(s):  
Liang Zhou

A serial of aminophosphonates zirconium with the different arm lengths of –(CH2)n– organic chains (n=2–6) was synthesized for the first time. These compounds are characterized by FT-IR, SEM, TEM, TG and nitrogen adsorption-desorption. And based on the experimental data, these materials not only have layer structure mesoporous and good thermal stability such as zirconium phosphate, but also can be adjusted the layer distance, pore size and pore volume. So aminophosphonates zirconium posses special excellent properties and will have potential prospect applications.


Author(s):  
T. F. Kouznetsova ◽  
A. I. Ivanets ◽  
J. D. Sauka

Titania-silica membranes on a porous quartz substrate are prepared by its direct contact with metal silicate sol at various Ti/Si ratios in the conditions of coagel sedimentation and presence of cetylpyridinium chloride. The study of textural and adsorption properties of membranes is conducted by low-temperature nitrogen adsorption-desorption, including methods of t-plots and DFT theory. It was shown that obtained membranes have mesoporous structure with the specific surface area and pore hydraulic diameter varied in intervals of 64–217 m2 /g and 4–11 nm, respectively. Developed values of surface area remain up to molar ratio of Ti/Si = 50/50.


Nanomaterials ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 1156 ◽  
Author(s):  
Nayda P. Arias ◽  
María E. Becerra ◽  
Oscar Giraldo

The focus of this paper is centered on the thermal reduction of KMnO4 at controlled temperatures of 400 and 800 °C. The materials under study were characterized by atomic absorption spectroscopy, thermogravimetric analysis, average oxidation state of manganese, nitrogen adsorption–desorption, and impedance spectroscopy. The structural formulas, found as a result of these analyses, were K 0.29 + ( M n 0.84 4 + M n 0.16 3 + ) O 2.07 · 0.61 H 2 O and K 0.48 + ( M n 0.64 4 + M n 0.36 3 + ) O 2.06 · 0.50 H 2 O . The N2 adsorption–desorption isotherms show the microporous and mesoporous nature of the structure. Structural analysis showed that synthesis temperature affects the crystal size and symmetry, varying their electrical properties. Impedance spectroscopy (IS) was used to measure the electrical properties of these materials. The measurements attained, as a result of IS, show that these materials have both electronic and ionic conductivity. The conductivity values obtained at 10 Hz were 4.1250 × 10−6 and 1.6870 × 10−4 Ω−1cm−1 for Mn4 at 298 and 423 K respectively. For Mn8, the conductivity values at this frequency were 3.7074 × 10−7 (298) and 3.9866 × 10−5 Ω−1cm−1 (423 K). The electrical behavior was associated with electron hopping at high frequencies, and protonic conduction and ionic movement of the K+ species, in the interlayer region at low frequencies.


2014 ◽  
Vol 968 ◽  
pp. 49-52
Author(s):  
Qin Qin Hou

A new nanocomposite, semiconducting polythiophene (PT) confined in mesoporous silica (SBA-15) was synthesized. PT was formed in the pores of SBA-15 by subsequent oxidative polymerization with FeCl3. Different techniques were used to characterize the nanocomposite formation. X-ray diffraction (XRD) and N2 adsorption/desorption analysis showed that the nanocomposite possesses mesoporous structure, and the residual pore volume of nanocomposite was significantly lower than that of pure empty SBA-15. Scan electron micrographs confirmed the presence of polythiophene inside pore channels of the host, and thermogravimetric analysis proved confinement effect in the channel system.


2014 ◽  
Vol 805 ◽  
pp. 678-683
Author(s):  
Ângela da Costa Nogueira ◽  
Jocielys Jovelino Rodrigues ◽  
Liliane Andrade Lima ◽  
Meiry Glaúcia Freire Rodrigues

In this study catalysts Fe/SBA-15 were prepared for Fischer-Tropsch Synthesis. SBA-15 samples were synthesized under acidic conditions using triblock copolymer Pluronic as a template and tetraethyl orthosilicate as a silica source.The molar composition was: 1.0 TEOS: 0017 P123: 8.14 HCl: 168 H2O. Fe/SBA-15 catalysts with different iron loading (15 wt. % and 20 wt. %) were prepared by wetness impregnation of relative SBA-15 with the desired amount of aqueous iron nitrate. The obtained catalyst were characterized by X ray diffraction (XDR), nitrogen adsorption-desorption and energy dispersive X-ray spectrometry (EDX). After impregnation of Fe the XRD profiles were almost unchanged and exhibited the high diffraction peaks of SBA-15 at low angles. The analysis of nitrogen adsorption-desorption was observed that the values of specific surface area decreased as the concentration of metal impregnated increased. And by the EDX analysis verified that the iron contents obtained are close to nominal levels of iron.


2021 ◽  
Vol 259 ◽  
pp. 04001
Author(s):  
Zane Abelniece ◽  
Valdis Kampars ◽  
Helle-Mai Piirsoo ◽  
Aile Tamm

CuO on mesoporous silica catalyst was prepared with post synthesis impregnation method, and the effects of Al and Co promoters on CuO/SBA-15/kaolinite catalyst properties and CO2 hydrogenation were studied. The mixing technology with kaolinite clay (containing Al2O3) was used to obtain the granules and to enhance the CO2 conversion to methanol as a product. The performance of all catalysts for catalytic hydrogenation of CO2 was evaluated on a fixed-bed tubular micro-activity reactor at 20 bar and 250°C with H2/CO2 molar ratio 3:1. XRD analysis, N2 adsorption-desorption analysis and SEM-EDX analysis indicated that the mesoporous structure of SBA-15 remains after loading with CuO and promoters, and after mixing with kaolinite clay. Results were compared with results obtained with commercial CuO/Al2O3 catalyst, which showed high MeOH selectivity (78%) during CO2 hydrogenation reaction.


2010 ◽  
Vol 03 (03) ◽  
pp. 161-164 ◽  
Author(s):  
XI LONG ◽  
CHUNXIA ZHAO ◽  
WEN CHEN

The present paper studies a kind of mesoporous carbon (MC) with high electrochemical performance, which was prepared by vapor infiltration method. The microstructure and electrochemical properties of the mesoporous carbon were investigated by transmission electron microscopy (TEM), nitrogen adsorption–desorption isotherms, cyclic voltammetry (CV), constant current charge–discharge cycling (CD), and the long-term stability test. The results indicated that the mesoporous carbon has an ordered mesoporous structure, with pore size of about 3.87 nm and surface areas of 1087 m2 ⋅ g-1. The cyclic voltammetry curve reveals typical electrical double-layer capacitor property. After 200 cycles, the CV curves can almost be overlapped, which indicates excellent cycling stability. From the charge/discharge cycling, the specific capacitance of MC is 117 F ⋅ cm-1 in 1.0 M KNO3 electrolyte media at a scan rate of 1.0 mV ⋅ s-1, which decays with increasing current density. The charge–discharge efficiency also decays with it.


2011 ◽  
Vol 204-210 ◽  
pp. 1245-1249 ◽  
Author(s):  
Quan Min Xue ◽  
Ying Shu Liu ◽  
Peng Huo

A promising adsorbent for CO2removal was prepared by introducing methyl-diethyl-amine (MDEA) into mesoporous silica SBA-15 using impregnation method. The MDEA modified adsorbents were characterized by X-ray powder diffraction (XRD) and nitrogen adsorption/desorption. Surface area, pore size and pore volume of MDEA-modified SBA-15 adsorbent decreased with the increasing of MDEA loading, while the loaded MDEA could not change the structure of the adsorbents. The adsorption performance of CO2on the adsorbents was conducted in a dynamic setup. Dynamic adsorption performance changed with change of the amount of loaded MDEA. In addition, not only the adsorbent was regenerable by purging with the purified gas, but also the adsorption performance is stable in adsorption cycles. The results indicated that the MDEA modified adsorbents were novel for removing CO2for biogas upgrading.


2013 ◽  
Vol 832 ◽  
pp. 132-137 ◽  
Author(s):  
Azry Borhan ◽  
Mohd Faisal Taha ◽  
Athirah Amer Hamzah

The preparation of activated carbon from wood-based industrys residue is one of the most environmental friendly solutions of transforming negative-valued wastes to valuable materials. Wood sawdust was first chemically activated using potassium hydroxide, KOH and characterized by nitrogen adsorption-desorption isotherms measured in Micrometrices ASAP 2020 and Field Emission Scanning Electron Microscope (FESEM). By manipulating three different parameters, the optimal activation conditions were found at temperature of 500°C, activation time of 60 min and impregnation ratio of 1:3. Results showed that the BET surface area, total pore volume and diameter of activated carbon were 1876.16 m2g-1, 0.88 cm3g-1and 6.93 nm, respectively. Nitrogen adsorption desorption isotherm analysis proved the existence of mesopores in activated carbon produced, suggesting that it can be effectively used as an adsorption material.


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