In this study, a new composite film consisting of polyethylene (PE)/oxide minerals (bentonite, silica, and diatomite) was successfully synthesized. Polymer modification was carried out by melting ...method. Coating of oxide minerals with PE has shown important results for size control, stabilization and increasing strength. Benzoyl chloride was used as a modifying material in the mechanism. According to the mechanism, it increases the interactions between the mineral and polyethylene through adsorption of the polymer backbone by ion pairing. The resulting composite materials were characterized using advanced analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared spectrophotometry (FTIR), Derivative thermogravimetry (DTG) and Thermogravimetric Analysis (TGA). The morphological structures of the composites were examined by scanning electron microscopy (SEM). SEM and FTIR analyses showed that bentonite, silica, and diatomite were modified with PE using an extruder device. At the same time, mechanical test results showed that the tensile strength of films containing 5% oxide mineral is higher than that of pure polyethylene film. In addition, the homogeneous appearance of the surfaces of the films has changed from porous to brittle appearance with the increase in the oxide mineral ratio in composite films. It was found that with the increase in the percentage of minerals in composite films using modified oxide minerals, porous and brittle structures do not form much on the film surfaces, and the interaction of the mineral with the polymer matrix increases. The study had important results in terms of emphasizing the cost-effectiveness of the modification of different minerals with PE, the suitability of production by smelting method and the improvement of mechanical properties. In addition, it is important to obtain different composite derivatives for use in the industrial field.
The composite consisted of clay and polymers like polyethylene (GCP) was used to remove methylene blue (MB) from the water. The most effective pH, temperature and initial dye concentration in ...adsorption process were found to be 9, 55 °C and 5 × 10
−6
M, respectively. The results of the experiment showed that the adsorption process was compatible with the pseudo-second-order model. Activation parameters of Δ
G
: − 70.64 K J mol
−1
, Δ
S
: − 70.64 J mol
−1
K
−1
,
E
a
: 12.37 K J mol
−1
at 308 °C were calculated and showed that adsorption process was exothermic and spontaneous. The results revealed that adsorption of MB on composite GCP was spontaneous and the composite of GCP
f
could be used for removing of MB from the water.
AgFe2O4@MWCNT nanocatalysts were successfully synthesized by following a series of physicochemical hydrothermal processes and characterized by various instruments such as XRD, TEM, Raman, UV-Vis ...spectroscopy, and XPS techniques. The activity of the nanocatalyst was assessed by examining the degradation of methylene blue (MB) through combined adsorption and heterogeneous sonocatalysis. AgFe2O4@MWCNT nanocatalysts exhibited better removal efficiency in the case of pre-adsorption followed by sonocatalytic reaction as compared to the simultaneous adsorption and sonocatalysis system. The effects the AgFe2O4@MWCNT nanocatalysts on the sonocatalytic activity were investigated in details by various experimental parameters such as solution pH (5.5–10), catalyst dosage (8–20 mg L−1), hydrogen peroxide (H2O2) dosage (5–20 mM), temperature (298–328 K), and dye concentration (12–40 mg L−1). The results revealed that the efficiency of AgFe2O4@MWCNT in MB degradation after sonocatalytic activity under optimum conditions was found to be about 98.5% in 75 min. Furthermore, OH• and O2• radicals exhibited the crucial molecular functions in the degradation of MB under sonocatalytic conditions in the presence of AgFe2O4@MWCNT nanocatalysts.The intermediate products after the degradation of MB were characterized by the GC-MS technique Based on the results, the adsorption followed by sonocatalytic degradation in the presence of AgFe2O4@MWCNT nanocatalysts showed great potential for the efficient treatment of wastewater.
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•AgFe2O4@MWCNT nanocatalysts were synthesized by following a series of physicochemical hydrothermal processes.•AgFe2O4@MWCNT nanocatalysts were successfully applied for the degradation of methylene blue.•The OH• radicals were found to be very effective in the MB degradation.
In this research, adsorption properties of bovine serum albumin (BSA) on diatomite clay, which is an oxide mineral, were studied as a function of BSA, sodium phosphate buffer and protein ...concentration and pH and the thermodynamic parameters of adsorption process were investigated. The BSA adsorption experiment onto diatomite clay indicated that the BSA solution reached the maximum adsorption value at pH 5.5. It was observed that the maximum adsorption capacity (qm) of the data obtained from the adsorption studies showed a great dependence on pH. The maximum amount of adsorption in adsorption experiments can be considered as points where the electrostatic interaction for pH is appropriate. Both structural and electrostatic interaction in regions outside of the isoelectric point may have caused a decrease in BSA absorbance. The structural influences were associated with different conformational states that while BSA molecules accept changes with pH, electrostatic effects can be observed in BSA molecules behaved like soft particles. In this case, it is not possible to explain the independence of the qm–pH curves of the amount of adsorption. The protein molecules at this point are very stable. Because this value is close to the isoelectric point of serum albumin. The surface structural change of BSA and diatomite clay was studied. For this, Fourier transform infrared spectroscopy (FTIR) spectroscopy values were compared before and after the experiment. The diatomite samples used as support material were characterized by FTIR, scanning electron microscopy, thermogravimetric analysis and Brunauer Emmett–Teller surface area analysis. The thermodynamic functions such as enthalpy, entropy, Gibbs free energy and activation energy were investigated in their experimental work. The thermodynamic parameters such as Gibbs free energy (Δ
G
*),
E
a
, Δ
H
* and Δ
S
* were calculated as − 67.45, 15.41, − 12.84 kJ mol
−1
and − 183.28 J mol
−1
K
−1
for BSA adsorption, respectively. We can deduce that the adsorption process from the data obtained from the thermodynamic parameters is spontaneous and exothermic. The adsorption of the process was investigated using Eyring and Arrhenius equations, and its adsorption kinetic found to be coherent with the pseudo-second-order model. As a result, we reached that the diatomite clay is a suitable adsorbent for the BSA. Experimental results showed that diatomite clay has the potency to be used for rapid pretreatment in the process of identifying proteins.
In the present work, SnO
2
-Fe
3
O
4
@MWCNT nanocatalyst was fabricated according to a sonochemical-hydrothermal procedure. The surface morphology and structure analyses of the synthesized SnO
2
-Fe
...3
O
4
@MWCNT were investigated by transmission electron microscope (TEM), X-ray diffraction (XRD), Raman spectroscopy, EDS, FTIR and BET analyses. The degradation efficiency of SnO
2
-Fe
3
O
4
@MWCNT nanocatalyst in MB solution was tested by several experimental conditions such as SnO
2
-Fe
3
O
4
@MWCNT dosage (8–20 mg/L), initial MB concentration (20–50 mg/L), initial solution pH (5–9), and ultrasonic output power (37–60 kHz). SnO
2
-Fe
3
O
4
@MWCNT nanocatalyst retained its efficiency as 85% at common experimental conditions of 16 mg/L of SnO
2
-Fe
3
O
4
@MWCNTs, 45 mg/L of MB, pH of 8, H
2
O
2
of 15 mM, and 60 kHz in 60 min under ultrasonic irradiation. In addition, the optimum experiment conditions for SnO
2
-Fe
3
O
4
@MWCNTs in MB degradation were investigated. The experiment result showed that the degradation efficiency of MB was increased by adding H
2
O
2
to the reaction medium due to forming more free radicals. Further, it was detected that OH• radicals were determined to be the dominant oxidative species in MB degradation using SnO
2
-Fe
3
O
4
@MWCNT catalyst. The reuse tests showed that SnO
2
-Fe
3
O
4
@MWCNT sonocatalyst preserved its very stable structure after using the same catalyst 5 times. The intermediates and by-products after MB degradation using the catalyst were indicated by GC–MS analysis. Overall the results showed that the SnO
2
-Fe
3
O
4
@MWCNT sonocatalyst has excellent potential for treating organic pollutants in wastewater.
Graphical Abstract
•NiCeO2@f-MWCNT/EDA nanomaterials were synthesized by a facile method.•Various advanced analytical methods revealed the chemical composition of NiCeO2@f-MWCNT/EDA nanomaterials.•NiCeO2@f-MWCNT/EDA ...nanomaterials exhibited an excellent specific capacitance of 2385 Fg−1.
Metal oxide and carbon nanotube-based materials are widely preferred in supercapacitor and electrochemical sensor applications due to their interesting physicochemical structure. In this paper, we report the synthesis, characterization, and utilization of NiCeO2@f-MWCNT/EDA nanoparticles as electrode materials for supercapacitor applications. The characterization studies of NiCeO2@f-MWCNT/EDA nanomaterials were performed using X-ray diffraction (XRD), Transmission electron microscope (TEM), and Raman spectroscopy apparatus. The characterization methods revealed a good distribution of NiCeO2 on f-MWCNT/EDA and formed a new structure of NiCeO2@f-MWCNT/EDA nanoparticles. Electrochemical studies of NiCeO2@f-MWCNT/EDA nanoparticles showed a significant specific capacitance of between 2385 and 603 Fg−1 with good cyclic stability of 1000 cycles with capacity retention between 42% and 1.4% at 10 mV/s scan rate. The obtained results reveal that the prepared NiCeO2@f-MWCNT/EDA nanoparticles are promising electrode materials for supercapacitor devices.
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In this study, Fe
3
O
4
/Mn
3
O
4
/CuO nanoparticles were synthesized, characterized, and used as a nanocatalyst in methylene blue (MB) degradation under ultrasonic conditions. The synthesis of Fe
3
...O
4
/Mn
3
O
4
/CuO nanoparticles was carried out according to a facile method and characterized using some analytical techniques such as FTIR, scanning electron microscopy (SEM) with transmission electron microscopy (TEM), EDS, and X-ray diffraction (XRD). The obtained Fe
3
O
4
/Mn
3
O
4
/CuO nanoparticles showed a very homogeneous structure, and the average particle size was determined as 1.87 nm. XRD analyses revealed that Fe
3
O
4
/Mn
3
O
4
/CuO nanoparticles have a 2.27 nm crystalline particle size. The chemical composition of Fe
3
O
4
/Mn
3
O
4
/CuO nanoparticles was well detected by FTIR and SEM–EDS analyses. The products formed after the degradation of MB were detected by gas chromatography–mass spectrometry (GC–MS). The degradation of MB was investigated with several experimental conditions using Fe
3
O
4
/Mn
3
O
4
/CuO nanoparticles, and optimum experiment conditions were detected to be T = 301 K, MB = 0.03 g/L, Cat. = 1.0 g/L, H
2
O
2
= 5 mM, Ult. = 60 kHz. A maximum of 95.04% MB degradation using Fe
3
O
4
/Mn
3
O
4
/CuO nanoparticles was achieved in 150 min. To detect the radical effectiveness, t-butanol, ethanol, and t-butanol scavenger solvents were tested, and it was detected that these scavenger solvents prevent the formation of radicals that are effective in MB degradation. As a result, the present work paves the way to prepare excellent and highly efficient sonocatalysts for the degradation of organic dyes.
Reduced-graphene-oxide-supported Ni nanoadsorbents (Ni@rGO) were synthesized in this work to remove methylene blue (MB) dye from aqueous solutions using ultrasonic process method. These synthesized ...nanoadsorbents were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, N2 sorption, and X-ray photoelectron spectroscopy (XPS) apparatus. The effect of independent parameters (initial dye concentration, H2O2 concentration, adsorbent particle concentration, initial pH, contact time, and temperature were investigated) on dye removal efficiency with Ni@rGO nanoadsorbents. The zero charge points (pHzpc) of the Ni@rGO composite particles were determined by using experimental results. The max adsorption capacity (qemax) of the removal of methylene blue (MB) with Ni@rGO was determined as 946.12 mg g−1 as a result of experimental data under optimum conditions using ultrasonic process method. The experimental data obtained in the kinetic study concluded that the adsorption process was more consistent with the pseudo second-order model. Thermodynamic functions such as Gibbs free energy change (ΔG0), entropy change (ΔS0) and enthalpy change (ΔH0) values were investigated in order to get an idea about the working mechanism of MB as a result of adsorption interaction with Ni@rGO composite particles. As a result of all the data obtained Ni@rGO nanoadsorbent has proven to be an effective nanoadsorbent material to remove methylene blue from aqueous solution under different parameters in ultrasonic process systems.
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•Superior Ni nanoadsorbents were synthesized to remove MB dye from aqueous solutions.•The max adsorption capacity was determined as 946.12 mg g−1.•O2 radicals have an important function on dye removal efficiency.•Prepared nanoadsorbent was highly stable and efficient after five trials.
PtCo based nanoparticles in alloy structure were synthesized using the microwave-assisted reduction method. These nanoparticles were deposited on different carbon supporting materials. Here, these ...supporting materials such as rGO (reduced graphene oxide), rGO-VC (vulcan carbon) and AC-VC (activated carbon-vulcan carbon) were used and the methanol oxidation reaction (MOR) activity of single carbon support and hybrid carbon support material in the presence of PtCo nanoparticles were investigated at the same molar concentration. The average particle size of the PtCo nanoparticles detected in the TEM analysis was found to be 3.55 ± 0.64 nm. The MOR activity of the PtCo@rGO, PtCo@rGO-VC and PtCo@AC-VC catalysts was determined, where the anodic peak current of PtCo@AC-VC was determined as 73 mA/cm2. It has been observed that PtCo nanoparticles with carbon hybrid support structures are more advantageous than single support structures due to the synergistic effect between carbon support structures and providing a larger surface area. Compared to previous studies, the MOR activity of PtCo@AC-VC is quite high. It can be stated that PtCo@AC-VC has comparable catalytic activity compared to the commercial available anode catalyst.
•PtCo nanoparticles were synthesized using the microwave-assisted reduction method.•The average particle size of the PtCo nanoparticles was found to be 3.55 nm.•The anodic peak potential of PtCo@AC-VC was determined as 73 mA/cm2.•PtCo@AC-VC is a highly efficient catalyst in direct methanol fuel cells.
In this study, we report a facile and effective production process of palladium nanoparticles supported on polypyrrole/reduced graphene oxide (rGO/Pd@PPy NPs). A novel electrochemical sensor was ...fabricated by incorporation of the prepared NPs onto glassy carbon electrode (GCE) for the simultaneous detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA). The electrodes modified with rGO/Pd@PPy NPs were well decorated on the GCE and exhibited superior catalytic activity and conductivity for the detection of these molecules with higher current and oxidation peak intensities. Simultaneous detection of these molecules was achieved due to the high selectivity and sensitivity of rGO/Pd@PPy NPs. For each biomolecule, well-separated voltammetric peaks were obtained at the modified electrode in cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements. Additionally, the detection of these molecules was performed in blood serum samples with satisfying results. The detection limits and calibration curves for AA, DA, and UA were found to be 4.9 × 10
, 5.6 × 10
, 4.7 × 10
M (S/N = 3) and ranging from 1 × 10
to 1.5 × 10
M (in 0.1 M PBS, pH 3.0), respectively. Hereby, the fabricated rGO/Pd@PPy NPs can be used with high reproducibility, selectivity, and catalytic activity for the development of electrochemical applications for the simultaneous detection of these biomolecules.
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