Showing papers in "Journal of Inorganic and Organometallic Polymers and Materials in 2017"
TL;DR: In this article, the structural and electronic properties of 5-fluorouracil (5-FU) anticancer drug with graphene oxide nanosheet (GONS) using density functional theory (DFT) and molecular dynamics (MD) simulation are investigated.
Abstract: In this work, we have studied the calculations for the interaction of 5-fluorouracil (5-FU) anticancer drug with graphene oxide nanosheet (GONS) using density functional theory (DFT) and molecular dynamics (MD) simulation. The structural and electronic properties of 5-FU molecule interacting with GONS are investigated by DFT methods. The process of 5-FU drug adsorption on different functional groups of GONS is exothermic and the optimized geometries are stable. The interaction energy values indicate that 5-FU molecule can be physically adsorbed on the GONS. It is found that at the most stable structure of 5-FU/GONS complexes, the hydrogen bond (HB) interactions between 5-FU molecule and the functional group of GONS predominate. As well as, the reliable assessment of dynamics drug adsorption on the GO surface is examined by complementing traditional analyses of MD simulations in the water solution at various temperatures (250, 300, 350 and 400 K). MD simulation results show that 5-FU drugs are strongly adsorbed on the Graphene oxide surface by increasing the temperature from 250 to 400 K, as reflected by the most negative van der Waals (vdW) interaction energy and a high number of hydrogen bonds between GONS and drug molecules.
80 citations
TL;DR: In this article, the preparation of cadmium oxide (CdO) thin films with different molar concentrations on glass substrate by simple and low cost SILAR (Successive Ionic Layer Adsorption and Reaction) method was reported.
Abstract: This work reports the preparation of cadmium oxide (CdO) thin films with different molar concentrations on glass substrate by simple and low cost SILAR (Successive Ionic Layer Adsorption and Reaction) method. The characterization, XRD pattern confirmed the presence of polycrystalline CdO in the deposited thin films with the cubic structure. The surface morphology and elemental composition of prepared thin films have been examined by scanning electron microscopy equipped with energy dispersive X-ray (EDX) analysis system. The optical property of the films was analyzed by UV–visible spectroscopy. The band gap of the deposited thin films was estimated by Tauc’s plot and it was found to be 2.6–2.8 eV. The prepared thin films were examined for the decomposition of the Methylene Blue (MB) dye which was visualized by UV-Visible spectroscopy, by decreasing the intensity of absorbance and concentration.
55 citations
TL;DR: In this article, an efficient, one-pot multicomponent procedure for good to excellent yield preparation of 2-amino-4H-chromene-4-carboxylate and 2-Amino-5H-pyrano[3,2-c]chromene 4-caroxylate using Fe3O4@SiO2-NH2 nanoparticles as a facile synthesized, easily recoverable, heterogeneous catalyst was investigated.
Abstract: An efficient, one-pot multicomponent procedure for good to excellent yield preparation of 2-amino-4H-chromene-4-carboxylate and 2-amino-5H-pyrano[3,2-c]chromene-4-carboxylate using Fe3O4@SiO2–NH2 nanoparticles as a facile synthesized, easily recoverable, heterogeneous catalyst was investigated. The amine-functionalized silica-supported magnetic catalyst was characterized successfully by Fourier transforms infrared spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy analyses. Using ethanol as a green solvent in these multicomponent reactions and no significant decrease in catalytic activity of the nanocatalyst during recovering process are other major points in this worthy chromene derivatives synthesis.
54 citations
TL;DR: In this paper, the role of poly(ethylene glycol) (PEG) on the formation of calcium carbonate particles was examined by studying the effect of PEG on calcite crystals.
Abstract: The role of polymer in precipitation has been examined by studying the effect of poly(ethylene glycol) (PEG) on the formation of calcium carbonate particles. Absence of polymer led to the formation of calcite crystals. Introduction of poly (ethylene glycol) molecules reduced the rate of crystallization process, and the effect is dependent on molecular weight and concentration. In the presence of 0.01 mol L-1 PEG, after 3 h of precipitation initiation, aragonite, vaterite phase appeared in the system. The calcium carbonate obtained with PEG was characterized by smaller sized particles in comparison with the ones without polymer. The CaCO3 particles were characterized by several techniques, such as FTIR, XRD, SEM, and particle size distribution analysis.
47 citations
TL;DR: In this article, the electrical properties of polyvinyl pyrrolidone (PVP) and poly vinyl alcohol (PVA) polymer electrolyte films were analyzed by solution casting technique.
Abstract: Sodium ion conducting polymer blend thin films are of technologically interesting due to the tuned physical and electrical properties with wide variety of applications like sodium sulphur batteries, thermoelectric generators, electrochemical sensors, etc. sodium ion conducting composite blend polymer electrolyte films, based on poly vinyl alcohol (PVA) and poly(vinyl pyrrolidone) (PVP) complexed with NaCl were prepared by solution casting technique. The prepared films were characterized by various methods. The complexation of the salt with the polymer blend was identified by X-ray diffraction and Fourier transforms infrared spectroscopy. DSC was used to analyze the thermal behavior of the samples and the glass transition temperature is low for the highest conducting polymer material. The Frequency and temperature dependent of electrical conductivities of the films were studied using impedance analyzer in the frequency range of 1 Hz–1 MHz. The higher electrical conductivity of 50 PVA:50 PVP:15 wt% NaCl concentration has been found to be 1.747 × 10−3 Scm−1 at room temperature. The electrical permittivity of the polymer films have been studied for various temperatures.
46 citations
TL;DR: In this article, solid state ion conducting polymer electrolyte films were prepared by doping nano-sized TiO2 particles on PVP (poly vinyl pyrrolidone) complexed with MgSO4·7H2O salt by solution casting technique and characterized by powder XRD, DSC, SEM, optical and dielectric studies.
Abstract: The study and application of thin film technology is entirely entered in to almost all the branches of science and technology. Transparent conducting oxide films have been widely used in the fields of flat panel displays, solar cells, touch panels and other optoelectronic devices owing to their high electrical conductivity and optical transmittance in visible region. In the present study, Solid state ion conducting polymer electrolyte films were prepared by doping nano-sized TiO2 particles on PVP (poly vinyl pyrrolidone) complexed with MgSO4·7H2O salt by solution casting technique and characterized by powder XRD, DSC, SEM, optical and dielectric studies. The XRD pattern of the prepared sample shows the semi-crystalline nature. SEM and EDS confirms the presence of compounds inside the material. Optical absorption studies are used to measure the bandgap of the prepared sample. Dielectric studies are performed to observe the conductivity of the sample.
44 citations
TL;DR: In this article, the authors focus on the covalent and noncovalent modification of both graphene and graphene oxide recently reported, and review the interesting properties, e.g., wider electrical band gap and higher dispersibility.
Abstract: Graphene, as one of the most promising new materials, has a wide range of applications in biosensors, super-capacitors and catalysts. Herein, we focus on the covalent and noncovalent modification of both graphene and graphene oxide recently reported, and review the interesting properties, e.g., wider electrical band gap and higher dispersibility. We cover covalent derivatization of graphene and graphene oxide with various species, such as nitrenes, carbenes, aryl intermediates, polymers, biomaterials, carbon materials (fullerenes and carbon nanotubes), and organic molecules. As regards, noncovalent functionalization, we consider π–π interactions, van der Waals forces, ionic interactions, and hydrogen bonding. This review also covers some efforts to achieve tailored functionalization for applications. Finally, we assess the future prospects of covalently and noncovalently modified graphene and graphene oxide (Fig. 1).
44 citations
TL;DR: In this article, three Schiff base compounds were synthesized via condensation of 3-R-4-amino-5-hydrazino-1,2,4-triazole with dibenzoylmethane.
Abstract: Three new Schiff base compounds were synthesized via condensation of 3-R-4-amino-5-hydrazino-1,2,4-triazole with dibenzoylmethane [R = H, CH3, and CH2CH3 namely L1, L2, and L3, respectively]. The synthesized Schiff bases were characterized using melting point, CHN elemental analyses, FT-IR, and 1H-NMR. The corresponding Cu(II) Schiff base complexes were synthesized via refluxing the prepared Schiff bases with CuCl2·2H2O. The synthesized complexes have been characterized by means of different spectral tools (FT-IR, ESR, and UV–Vis spectra) in addition to elemental analysis, magnetic moment, conductivity, and thermal analysis. The synthesized copper complexes are nonelectrolytes in N,N-dimethylformamide (DMF) based on their conductance values. Using modified Bauer-Kirby method, the Schiff bases and their Cu(II) complexes have been tested for antifungal (Candida albicans and Aspergillus flavus) and antibacterial (Staphylococcus aureus and Escherichia coli) activities. Moreover, CuO nanoparticles were produced via thermal decomposition of the synthesized Cu(II) complexes at 650 °C. The produced nanoparticles were characterized using XRD, HR-TEM, FT-IR, and UV–Vis spectroscopy. The CuO nanostructures exhibited good photocatalytic activity for the degradation of methylene blue dye in the presence of hydrogen peroxide with 77.36% degradation efficiency in 360 min. Proposed structure of the synthesized Cu(II) complexes
44 citations
TL;DR: The synthesis by conventional bioreduction approach using quercetin compound from Clitoria ternateaL shows significant antimicrobial activity against multidrug resistant bacteria and the synthesized hybrid AgNPs showed less hemolysis activity compared with American Society for Testing and Materials range <5%.
Abstract: Currently, silver nanoparticles (AgNPs) have been providing unique approach to the treatment of infectious diseases. Therefore, herein we demonstrate AgNPs synthesis by conventional bioreduction approach using quercetin compound from Clitoria ternatea L. methanolic petal extract. Bioreduction of silver nitrate (AgNO3) with the quercetin extract, was incubated for 240 min and the mixture were characterized by UV–Vis spectroscopy, FTIR, XRD, DLS, SEM, EDS and Zeta potential analysis. The results were confirmed the presence of silver ion. Furthermore, the biosynthesized AgNPs possess significant antimicrobial activity against multidrug resistant bacteria such as, Staphylococcus aureus and Shigella sp. with maximum concentration (100 µl) showed strong inhibitory action. In addition, the hybrid AgNPs showed potential Quorum Sensing Inhibition activity with different concentration (25–100 µg/ml) against the AHL-mediated violacein production in C. violaceum (14–86%) and biofilm formation (19–92%), extracellular polymeric substances (16–72%), protease (17–93%) productions in S. aureus and. It was again confirmed by spectrophotometry and microscopy. Further, the synthesized hybrid AgNPs showed less hemolysis activity 4.58%, compared with American Society for Testing and Materials range <5%. Threfore our findings recommend that the biosynthesized AgNPs could be more hemocompatible for drug delivery applications.
43 citations
TL;DR: In this article, the synthesis, characterization, electrical conductivity, thermal and magnetic properties of magnetite (Fe3O4) nanoparticles containing polyindole (PIN)/poly(vinyl alcohol) (PVA) blend nanocomposite by in situ polymerization method.
Abstract: This paper demonstrates the synthesis, characterization, electrical conductivity, thermal and magnetic properties of magnetite (Fe3O4) nanoparticles containing polyindole (PIN)/poly(vinyl alcohol) (PVA) blend nanocomposite by in situ polymerization method. UV–Visible, FTIR, XRD, SEM, DSC, TGA and VSM analysis were employed to characterize the blend composite. The dielectric properties, AC and DC conductivity were studied with respect to different content of Fe3O4 particles in PIN/PVA. UV and FTIR spectrum indicates the strong interaction between the interfaces of nanoparticles and the blend matrix. XRD patterns confirmed the crystalline nature of nanocomposite. SEM images showed that the nanoparticles were uniformly dispersed into the polymer with good spherically shaped network structure. The glass transition and melting temperature of the composites were higher than the parent blend polymer and the thermal transitions increases with the concentration of nanoparticles. TGA results indicated that the thermal stability of nanocomposites were much higher than PIN/PVA and the thermal stability increased with the concentration of nanoparticles. Both AC and DC conductivity of the blend nanocomposite was much greater than blend and the maximum electrical conductivity was observed for 10 wt% of nanocomposite. Dielectric constant and loss tangent were found to be decreased with an increase in frequency, whereas these properties increased with the concentration of nanoparticles. Magnetic hysteresis loops shows the superparamagnetic nature of the composites. The saturation magnetization and remenance values of nanocomposites were increased with increase in content of magnetite nanoparticles.
40 citations
TL;DR: In this article, copper sulfide nanoparticles (CuS NPs) were synthesized using Calotropis gigantea leaf extract by adopting the sonochemical method, using a green approach.
Abstract: In this work, copper sulfide nanoparticles (CuS NPs) were synthesized using Calotropis gigantea leaf extract by adopting the sonochemical method, using a green approach. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared, UV–Vis DRS, fluorescence, thermal gravimetric analysis and zeta potential analyzers were used to characterize the synthesized CuS NPs. The photocatalytic degradation of safranin O (SO) dye revealed that the prepared CuS NPs exhibited efficient photocatalytic performance on sunlight irradiation. The degradation of dye in the absence and presence of catalyst was 6.44 and 80.53% in 60 min respectively. Moreover, the photodegradation of dye, when studied with reference to the amount of catalyst from 10 to 50 mg/L was found to be optimized. The SO dye was degraded sharply on the usage of 50 mg/L of the catalyst. The CuS NPs was employed as a sensor for the determination of various heavy metal ions using a fluorescence spectrophotometer and produced satisfactory results. The synthesized samples were screened for antibacterial and antifungal activities against selected bacterial and fungal strains with marked results.
TL;DR: In this article, the authors reported synthesis, structure characterization and methylene blue (MB) adsorption of a novel organic-inorganic hydrogel nanocomposite adsorbent (HNA) based on sodium alginate (NaAlg) and silicone dioxide nanoparticles (SiO2-NPs).
Abstract: In this work, we reported synthesis, structure characterization and methylene blue (MB) adsorption of a novel organic–inorganic hydrogel nanocomposite adsorbent (HNA) based on sodium alginate (NaAlg) and silicone dioxide nanoparticles (SiO2-NPs). The HNAs were prepared using grafting of acrylic acid (AA) onto NaAlg by using ammonium persulfate as a free radical initiator and methylene bisacrylamide as a crosslinker in the presence of SiO2-NPs, which synthesized in situ from the base-catalyzed hydrolysis of tetraethylorthosilicate (TEOS). The structure of HNAs were characterized by FTIR, SEM, EDX, TEM, XRD, UV–Vis and TGA techniques and a proposed mechanism for preparation of adsorbents was also suggested. The swelling capacity of HNAs was examined in buffer solutions with pH ranged 1.0–14.0. The nanocomposites exhibited a pH-responsiveness character so that a swelling-deswelling pulsatile behavior was recorded at pHs 2.0 and 9.0. The swelling kinetics of HNA was also preliminary investigated. Moreover, the effects of agitation time, pH, initial dye concentration, adsorbent dose, TEOS content, AA concentration and temperature were optimized with respect to dye adsorption capacity of HNAs in detail. Furthermore, the kinetic and adsorption isotherm of MB dye onto HNAs were investigated in detail. The HNAs also showed excellent regeneration capacity after five consecutive cycles of dye adsorption–desorption. In general, the results indicated that the synthesized adsorbents with biodegradability and biocompability properties can be used in wastewater treatment via dye adsorption.
TL;DR: In this paper, Nitrile rubber (NBR) based nanocomposite consisting of different concentrations of hydroxyapatite nanoparticles (HA) were prepared and characterized by FTIR, UV and X-ray diffraction studies.
Abstract: Nitrile rubber (NBR) based nanocomposite consists of different concentrations of hydroxyapatite nanoparticles (HA) were prepared and characterized by FTIR, UV and X-ray diffraction studies. The surface morphology of the nanocomposites were analyzed using SEM and optical microscopy. The glass transition temperature and thermal stability of NBR and its nanocomposites were done by DSC and TGA respectively. The electrical properties such as AC conductivity, dielectric constant and dielectric loss tangent were investigated in the frequency range of 102–106 Hz at room temperature. The FTIR spectra confirmed the interfacial interaction between NBR and the HA nanoparticles. The shift in the UV peak with broadness of composite indicates the formation of nanoparticles within the macromolecular chain of NBR. XRD pattern ascertained the ordered arrangement of nanoparticles with a decrease in the amorphous nature of parent polymer. Both the glass transition temperature and the thermal stability of the nanocomposites were higher than pure NBR and the glass transition temperature improved with the increase in concentration of nanoparticles in NBR composite indicating the strong interfacial adhesion between the polymer and nanoparticles. From DSC studies, thermodynamic parameters such as enthalpy and entropy change of the composites were also evaluated. AC conductivity of the nanocomposite was much greater than NBR and the magnitude of conductivity enhanced with the addition of nanoparticles. The observed enhancement in dielectric constant and dielectric loss tangent of composite with the increase in concentration of nanoparticle was attributed to the increase in number of interfacial interaction between the polymer and the nanoparticles.
TL;DR: In this paper, the authors used FTIR spectroscopy and XRD techniques for structural confirmation of CdO nanoparticles and PVA composite films and calculated the average grain size of the prepared films using Scherrer's formula, which was also confirmed by TEM.
Abstract: The CdO nanoparticles were prepared by sol–gel method and CdO doped polyvinyl alcohol (PVA) nanocomposite films were prepared by solution casting technique. The structural confirmation was carried out by FTIR spectroscopy and XRD techniques for the prepared films. The peak at 650 cm−1 was found to be Cd–O stretching in the FTIR spectrum. Also, the FTIR spectra confirmed the interaction between the hydroxyl groups of PVA and CdO nanoparticles. Moreover, the XRD analysis confirmed the structure of CdO and the interaction between PVA and CdO. The average grain size of CdO was calculated as 37.5 nm using Scherrer’s formula. This was also confirmed by TEM. The surface morphology of the prepared films was analyzed by scanning electron microscope. The optical studies were carried out using UV–Visible spectroscopy. The energy bandgap values of CdO and PVA composite films were calculated using Tauc’s plot. The DC conductivity measurement was also carried out for PVA composite films using two probe setup. Thermal stability of PVA nanocomposite films was accessed using thermogravimetric analysis.
TL;DR: In this article, the authors reported the preparation of Co3O4, α-Fe2O3, and CoFe 2O4 nanostructures through a hydrothermal method followed by a subsequent heat treatment.
Abstract: We herein report the preparation of Co3O4, α-Fe2O3, and CoFe2O4 nanostructures through a hydrothermal method followed by a subsequent heat treatment. The as-prepared nanostructures exhibited good adsorption properties for the removal of Orange G (OG) textile dye. Various parameters influencing the adsorption process have been investigated such as contact time, initial dye concentration, ionic strength, adsorbent dose, and temperature. The maximum adsorption capacity values were found to be 33.3, 53.2, and 62.0 mg/g, for Co3O4, CoFe2O4, and α-Fe2O3 nano-adsorbents, respectively. The adsorption data fit the pseudo-second-order kinetic and Langmuir isotherm models well. Based on the calculated thermodynamic constants: ΔH° (3.660, 14.82, and 0.4710 kJ/mol), ΔG° (from −0.8090 to −1.109, from −0.6444 to −1.682, and from −3.665 to −3.943 kJ/mol), and Ea (9.277, 5.060, and 12.10 kJ/mol), the adsorption of OG dye on the aforementioned nano-adsorbents, respectively, was found to be endothermic, spontaneous, and physisorption process. In addition, because of the relatively high adsorption capacity and chemical stability, the as-synthesized α-Fe2O3 adsorbent is suggested as a promising candidate for the removal of OG textile dye from aqueous solutions.
TL;DR: In this article, the solvothermal method was utilized to synthesize the crystal of ZIF-8 by taking the molar ratio of the metal ions to the organic ligands of 2:1 at 120°C.
Abstract: The solvothermal method was utilized to synthesize the crystal of ZIF-8 by taking the molar ratio of the metal ions to the organic ligands of 2:1 at 120 °C. This was the best technological condition. Meanwhile, as demonstrated in characterization of the X-ray diffraction (XRD), scanning electron microscope (SEM), thermogravimetry (TGA) and Fourier Transform infrared spectroscopy (FTIR). SEM was showed that the crystal of ZIF-8 was endowed with high crystallinity and prismatic structure, with the size range of 5–10 μm, the BET specific surface area of the crystal was 739.4 m2 g−1. TGA was showed that its thermal stability could live up to 600 °C. FTIR was showed that the acid is completely protonated, and the Zn2+ and the 2-Methylimidazole are formed the crystal ZIF-8, in addition, O–Zn adsorption peak also existed in the crystal ZIF-8. Then the structure activity relationship of the crystal ZIF-8 synthesis, thermal stability and N2 sorption property was studied.
TL;DR: In this paper, an advanced hybrid inorganic-organic geopolymeric material is developed by environmentally and user friendlier approach, where the authors showed that it is practical and better to adopt this greener solid state approach for preparation of geopolymer instead of user-unfriendlier hazardous alkaline solution based approach, to achieve sustainable growth in geopolymers as like Portland cement.
Abstract: In this research, advanced hybrid inorganic–organic geopolymeric material is developed by environmentally and user friendlier approach. The presented novel approach for geopolymer formation certainly overcomes the existing drawbacks of geopolymerization technology. The effect of rice husk ash and Na2O/SiO2 ratios on geopolymer gel formation and mechanical strength has been previously identified via solution chemistry route; however, development of geopolymeric material having hybrid inorganic–organic characters via together mechanochemical grinding of raw materials and effect of mechanochemically activated Na2SiO3 on geopolymeric properties via solid state route has never before been explored. Together mechanochemical grinding of raw materials of varying compositions in solid state resulted in the formation of ready to use geopolymeric precursors; which on just addition of water led to development of advanced hybrid inorganic–organic geopolymeric material with considerably enhanced properties. XRD, FTIR and SEM characterization data of developed geopolymeric precursor powder and hybrid inorganic–organic geopolymeric material are reported and discussed in detail. As the results of the investigations, the relationship between geopolymer composition, grinding mechanism and material properties established. The composition which exhibited synergistic effect of both rice husk and SMS is found to be excellent in performance. The study showed that it is practical and better to adopt this greener solid state approach for preparation of geopolymer instead of user-unfriendlier hazardous alkaline solution based approach, to achieve sustainable growth in geopolymers as like Portland cement.
TL;DR: In this article, the effect of activating agent sodium hydroxide (NaOH), zinc chloride (ZnCl2) and phosphoric acid (H3PO4) on textural properties, surface functional groups and electrochemical supercapacitance properties was thoroughly examined.
Abstract: Nanoarchitectonics of nanoporous carbon materials (NCMs) derived from natural resource; Areca Catechu Nut (ACN) with enhanced electrochemical supercapacitance properties is reported. ACN powder is chemically activated in a tubular furnace at 400 °C and the effect of activating agent sodium hydroxide (NaOH), zinc chloride (ZnCl2) and phosphoric acid (H3PO4) on the textural properties, surface functional groups and electrochemical supercapacitance properties was thoroughly examined. We found that ACN derived NCMs are amorphous in nature comprising of macropores, micropores and hierarchical micro- and mesopore architecture depending on the activating agent. Surface area and pore volume are found in the range 25–1985 m2 g−1 and 0.12–3.42 cm3 g−1, respectively giving the best textural properties for H3PO4 activated NCM. Nevertheless, despite the different chemical activating agent used, all the prepared NCMs showed similar oxygen-containing surface functional groups (carboxyl, carboxylate, carbonyl and phenolic groups). The H3PO4 activated NCM showed excellent supercapacitance properties giving a high specific capacitance of ca. 342 F g−1 at a scan rate of 5 mV s−1 together with the high cyclic stability sustaining capacitance retention of about 97% after 5000 charging/discharging cycles. Electrochemical supercapacitance properties have demonstrated that the ACN derived novel nanoporous carbon material would be a potential material in energy storage application.
TL;DR: Graphene-based composite material was prepared and its electrochemical supercapacitive properties were investigated in this article, where the composite material comprises of mixed manganese oxide (Mn2O3) and cobalt oxide (Co3O4) crystal distributed on the reduced graphene oxide (RGO) matrix.
Abstract: Graphene-based composite material was prepared and its electrochemical supercapacitive properties were investigated. The composite material comprises of mixed manganese oxide (Mn2O3) and cobalt oxide (Co3O4) crystal distributed on the reduced graphene oxide (RGO) matrix. Structure and morphology of the composite was studied by X-ray diffractometry, high resolution transmission electron microscopy and scanning electron microscopy. The surface functional groups and chemical composition were confirmed by Fourier transform infrared spectroscopy, Raman scattering spectroscopy and X-ray photoelectron spectroscopy. Thermal stability was investigated by thermo gravimetric analysis. Electrochemical supercapacitive performance of the composite was investigated by cyclic voltammetry (CV) and chronopotentiometry. CV and chronopotentiometry results suggested that electrochemical performance of the composite material is better than RGO and mixed Mn2O3 and Co3O4. Specific capacitance of composite was obtained 210 F g−1 at scan rate of 5 mV s−1 and 184 F g−1 at current density of 2 A g−1, respectively. Moreover, the composite showed high cyclic stability with the retention of about 87% capacitance after 1000 charge/discharge cycles. These results suggest the importance and potential of graphene based composite in supercapacitor application.
TL;DR: In this article, the effect of metal oxide particles on the structural, magnetic and thermal stability was analyzed by a high resolution transmission electron microscope (HRTEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA) measurements.
Abstract: Nanocomposites of poly(vinyl cinnamate) (PVCin) with various concentration of nickel oxide (NiO) nanoparticles were prepared by in situ polymerization method. The effect of metal oxide particles on the structural, magnetic and thermal stability was analyzed by a high resolution transmission electron microscope (HRTEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA) measurements. The electrical properties such as room temperature DC conductivity and temperature dependent AC conductivity were investigated with respect to different loading of NiO nanoparticles. XRD and HRTEM images showed the uniform arrangement of nanoparticles inside the macromolecular chain of PVCin. The VSM studies of nanocomposites indicated the hysteresis loops of the ferromagnetic behavior. The saturation of magnetization and coercivity values were varied with the content of NiO nanoparticles. From TGA analysis the composite attain better thermal stability than polyvinyl cinnamate and the thermal stability increases with increase in concentration of nanoparticles. The electrical conductivity of nanocomposite was increased with increase in temperature and also with the loading of nanoparticles. The activation energy values calculated from the AC conductivity was found to be decreases with increase in temperature in all compositions. AC and DC conductivity of nanocomposites were much greater than pure PVCin and the maximum conductivity values were obtained for 10 wt% of composite. Different theoretical equations based on Scarisbrick, McCullough and Bueche model were used to compare the experimentally determined conductivity with theoretical conductivities.
TL;DR: In this paper, a CVD method was used to synthesize MWCNTs with CH4 as carbon source over Co-Mo/MgO nanocatalyst at a temperature of 1000°C and then treated by two methods.
Abstract: In the present study, MWCNTs were synthesized through CVD method, employing CH4 as carbon source over Co-Mo/MgO nanocatalyst at a temperature of 1000 °C and then treated by two methods. First by KOH activation (A-MWCNTs), with a weight ratio of KOH: MWCNTs = 3:1 at 900 °C in He atmosphere and second treated by H2SO4: HNO3 = 3:1 (F-MWCNTs). MWCNT samples were characterized by FE-SEM, TEM, XRD, FT-IR, BET and Raman spectroscopy. The adsorption of H2 gas was performed using volumetric method. Various parameters on adsorption of H2 including surface defects, surface areas, pore characteristics and functional groups have been investigated. Furthermore, it was found that the hydrogen adsorption of P-MWCNTs, A-MWCNTs and F-MWCNTs were 0.67, 1.24 and 0.40 wt%, respectively at room temperature (298 K) while the pressure varied from 0 to 34 bar. The results indicated a considerable rise in the H2 adsorption capacity of A-MWCNTs (85%), due possibly to the high surface area and enhanced micro-pore volume and the defects formed on the surface sites of MWCNTs by KOH activation. In this case, hydrogen molecules adsorption on the defective cavities could have a significant role through van der walls forces. Therefore, it can be concluded that KOH-modified MWCNTs is one of the most significant ways of developing the textural characteristic and improving hydrogen storage properly.
TL;DR: In this article, the properties of hybrid polypyrrole (Ppy) and titanium oxide (TiO2) nanocomposite, synthesized using oxidative chemical polymerization method have been investigated.
Abstract: Optical and electronic properties of hybrid Polypyrrole (Ppy)–Titanium oxide (TiO2) nanocomposite, synthesized using oxidative chemical polymerization method have been investigated here. The synthesized organic–inorganic hybrid materials have been characterized using XRD, FT-IR, FESEM, UV–Vis, Raman, and TGA. Electrical conductance and dielectric behavior of the electrical phenomena of the sample have also been investigated. XRD results demonstrate the amorphous nature of Ppy, however, its composites with TiO2 exhibit crystalline nature. FT-IR spectroscopy reveals the presence of interaction between conducting Ppy and TiO2. UV–Vis study show changes in spectra of Ppy in presence of TiO2 with a slight increase in the band gap. The SEM results reveal encapsulation of TiO2 particles in Ppy matrix and agglomeration of grains have also been observed with evident changes in morphology with increasing percentages of TiO2. TGA data indicates that the composite materials show good thermal stability. Conductance results show that electrical conductivity of Ppy increases upon addition of TiO2. It has also been noticed that the dielectric parameters (dielectric constant, loss tangent) of Ppy vary with addition of TiO2. The resulting insight clearly suggests that by embedding TiO2 in Ppy the electrical properties of the composites can be improved.
TL;DR: In this paper, a high performance polymer poly aryl ether ketone (PAEK) is reinforced with micro and nano boron carbide (B4C) and functionalized multi walled carbon nanotubes (F-MWCNT) to investigate the individual and hybrid effect of the fillers.
Abstract: In the present study a high performance polymer poly aryl ether ketone (PAEK) is reinforced with micro and nano boron carbide (B4C) and functionalized multi walled carbon nanotubes (F-MWCNT) to investigate the individual and hybrid effect of the fillers. Optical microscopy and transmission electron microscopy suggested the dispersion of micro and nano fillers respectively in PAEK matrix. The inclusion of B4C nano fillers increased the hardness of the composites which aided the wear resistance of the composites. The morphological features of the worn surface of the samples are analyzed using scanning electron microscopy. It is found from the izod impact test analysis that the impact strength of the composite enhanced by the F-MWCNT inclusion. The thermal properties of PAEK in the composites are studied using differential scanning calorimetry and it revealed dominant effect of F-MWCNT influencing the thermal transitions than the B4C particles. The kinetics of thermal degradation of various composites is analyzed using Coats–Redfern method. The positive influence of B4C in the matrix indicates that the thermal degradation is delayed due to the higher activation energy it possesses. The overall results shows that the hybrid nanocomposite exhibits better properties compared to individual micro and nano composites.
TL;DR: In this article, a facile route for preparing LaFeO3/rGO nanocomposites comprising of metal oxide nanoparticles and graphene was demonstrated, which was used as an effective photocatalyst for the degradation of methyl orange (MO) dye under visible light irradiation.
Abstract: The present work demonstrates a facile route for preparing LaFeO3/rGO nanocomposites comprising of metal oxide nanoparticles and graphene. Structural, morphology, optical and photocatalytic studies of the samples were characterized using powder X-ray diffraction (XRD), FT-IR, Raman, high resolution scanning electron microscopy (HRSEM), high resolution transmission electron microscope (HRTEM), atomic force microscopy (AFM), thermogravimetry (TGA), X-ray photoelectron spectroscopy, UV–visible and photocatalytic. LaFeO3/rGO nanocomposites believed as an effective photocatalyst for the degradation of methyl orange (MO) dye under visible light irradiation. The inclusion of carbon enhances the light absorption of LaFeO3, resulting in the enhanced photocatalytic activity of the nanocomposite. The degradation of MO dye under visible light source was completely achieved using LaFeO3/rGO as a catalyst.
TL;DR: In this article, nano fillers Ag:ZnO have fairly improved the optical absorption, conduction and an enhanced current density of nanocomposites which can be used as electron transport layer in the OLED device fabrication.
Abstract: Nanostructured Ag-doped ZnO nanoparticles, and its polymeric nanocomposites (Ag:ZnO/PMMA) were synthesized in the laboratory via free radical polymerization process. The formation of PMMA matrix, its nanocomposites and relative changes in nano structured properties were examined by Fourier transform infrared spectroscopic (FTIR) analysis. Nanohexagonal structure was formed in the PMMA polymeric pattern with the incorporation of Ag:ZnO nano fillers, as examined by surface morphology images. Optical absorption spectra associated with the blue region of visible range and the optimized concentration showed reduced band gap ~2.55 eV which led to increase the p-type conductivity. Increased rate of electron–hole radiative recombination and an enhanced current density ~85.70% were examined. This revealed a significantly improved conductivity of the Ag:ZnO/PMMA nanocomposites. The nano fillers Ag:ZnO have fairly improved the optical absorption, conduction and an enhanced current density of nanocomposites which can be used as electron transport layer in the OLED device fabrication.
TL;DR: In this paper, the authors used Commelina nudiflora aqueous extract as stabilizing and reducing agent to synthesize Au-Ag alloy nanoparticles (NPs).
Abstract: In present study, biosynthesis of Au–Ag alloy nanoparticles (NPs) using Commelina nudiflora aqueous extract as a stabilizing and reducing agent is reported. The crystalline nature, size, shape and composition of synthesized Au–Ag alloy NPs were characterized by UV–Vis spectrophotometer, field emission scanning electron spectroscopy, energy dispersive X-ray spectroscopy, transmission electron microscope, X-ray diffraction and fourier transform-infrared spectroscopy (FT-IR). The synthesized Au–Ag alloy NPs exhibited different ranges of sizes between 20 and 80 nm with different morphology such as spherical, rod and triangular. FT-IR spectral data revealed that the plant extract contains amine, alcohol, phenol and alkane molecules which are critically involved in the formation of Au–Ag alloy NPs. Finally, the biosynthesized Au–Ag alloys NPs exhibited a strong minimum inhibitory, minimum bactericidal activity against selected oral pathogenic bacteria. The present study gives an important suggestion on plant extract mediated synthesis bimetallic NPs (Au–Ag alloy) emphasis on oral pathogenic bacteria activities.
TL;DR: In this paper, a simple co-precipitation-calcination process for synthesizing copper cobaltite (CuCo2O4) nanostructures with different morphologies such as nanasphere, nanorods, and nanosheets was reported.
Abstract: The present investigation reports a simple co-precipitation-calcination process for synthesizing copper cobaltite (CuCo2O4) nanostructures with different morphologies such as nanasphere, nanorods, and nanosheets using [Cu(en)2(H2O)2]Cl2 and [Co(en)3](NO3)3 as novel precursors. The obtained nanostructures were characterized by XRD, SEM, TEM, FTIR and DRS. Effect of precipitating agent, surfactant, and calcination temperature on morphology of prepared nanostructures was well studied. Moreover, the efficiency of CuCo2O4 nanostructures as a photocatalyst for the decolorization of azo dyes including Acid Brown 14 (AB14) and Acid Red 88 (AR88) using ultraviolet and visible light irradiation was evaluated and more than 79% of AB14 and 89% of AR88 were decolorized under UV light after 90 min, respectively. Also, the effect of particle size and morphology on the photocatalytic activity was evaluated.
TL;DR: In this article, a cobalt oxide (Co3O4) nanocatalyst was synthesized by solgel method using the protic ionic liquid namely 1-butylimidazolium glycolate as solvent and stabilizer.
Abstract: Cobalt oxide (Co3O4) nanocatalyst was synthesized by sol-gel method using the protic ionic liquid namely 1-butylimidazolium glycolate as solvent and stabilizer. The obtained Co3O4 nanocatalyst was characterized by powder X-ray diffraction (XRD), Fourier transform infrared, High resolution scanning electron microscopy (HR-SEM), Energy dispersive X-ray (EDX), High resolution transmission electron microscopy (HR-TEM), Selected area electron diffraction, UV–Visible diffuse reflectance spectroscopy, Photoluminescence spectroscopy, Brunauer–Emmett–Teller surface area and Vibrating sample magnetometer (VSM). Powder XRD results showed the well-crystalline cubic structure of synthesized Co3O4 with size of 19.29 nm. Also, the sphere-like morphology of Co3O4 nanocatalyst was confirmed by HR-SEM and HR-TEM images. Furthermore, the synthesized Co3O4 nanocatalyst possessed optical band gap values of 1.75 and 2.46 eV and hence acted as a semiconducting material. In addition, the presence of small hysteresis loop in Magnetic measurement (VSM) confirmed the ferromagnetic nature of Co3O4 nanoparticles. Moreover, the synthesized Co3O4 nanocatalyst found to be used in photo-catalytic degradation of methylene blue and exhibited 94.61% efficiency.
TL;DR: In this article, the preparation of magnetite supercapacitors by using a facile one-step solvothermal method, where Mn2+ has been used as the doping element to modify the electrochemical properties of Fe3O4.
Abstract: Supercapacitors with high power density and excellent cycle life are considered to be a promising energy storage system for electric vehicle application. Because of low cost and high abundant, the preparation of iron oxides-based supercapacitors has become significant. Here, we reported the preparation of magnetite supercapacitors by using a facile one-step solvothermal method, where Mn2+ has been used as the doping element to modify the electrochemical properties of Fe3O4. The simply prepared supercapacitor showed a much higher electrochemical capacitance in contrast to reported Fe3O4-based electrochemical capacitors. The electrochemical capacitance at this supercapacitor can be as high as 268.4 F g−1 when the Mn2+ doped reached 1.5 mmol. There was not significant decrease in the capacitance after recycling 600 at 2 A g−1 in KOH aqueous solution. The excellent properties in the supercapacitor share a promising prospect with the development of a next generation of high- performance energy storage devices.
TL;DR: In this paper, a change of the execution of polyamide thin-film composite (TFC) reverse osmosis (RO) membrane utilizing surface alteration by MgSiO3 nanoparticles was discussed.
Abstract: This study focuses on to the change of the execution of polyamide (PA) thin-film composite (TFC) reverse osmosis (RO) membrane utilizing surface alteration by MgSiO3 nanoparticles. This has been an expert by means of holding of the practical grafting of PA layer with magnesium silicate nanoparticles (MgSiO3) in the presence of 2-acylamido 2-methyl propane sulphonic acid (AMPS) as condensing monomer. To confirm the presence of MgSiO3 nanoparticles and to inspect the morphology of the TFC nanoparticles layer SEM, FT-IR, XRD, TGA and DMA analysis were used. The outcomes demonstrated that the AMPS are effectively joined on the TFC film surface with an upgrade in thermal and mechanical decencies contrasted with pristine TFC layer. Besides, the contact angle estimations demonstrate an increase in the hydrophilicity of the thin film surface by the addition of nanoparticles. The water flux and salt rejection of the modified membranes were 25 L/m2 h and 95.5%, respectively.