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[IEEE 2018 IEEE 2nd International Conference on Dielectrics (ICD) - Budapest (2018.7.1-2018.7.5)] 2018 IEEE 2nd International Conference on Dielectrics (ICD) - Characterization of LDPE-Metal Oxide Nanocomposites Using Thermo-Analytical and Spectroscopic Techniques
摘要： Polyethylene metal oxide nanocomposites find their application as high voltage insulation for direct current cables, to mitigate the space charge and other issues. Nano particles like SiO2, MgO, ZnO etc are used as filler materials in polyethylene matrix to achieve good electrical and mechanical properties like: space charge reduction, enhanced surface & volume resistivity and higher dielectric stress withstand capabilities. Surface modification of metal particles is usually done by treating the nanoparticles with silane to have good distribution and dispersion of metal particles. However, characterization of nanocomposite based on spectroscopic and thermo-analytical techniques is very essential to understand its long term performance and its reliability when used as insulation in HVDC extruded power cables. Different metal oxide nanoparticles such as MgO and SiO2 have been investigated as fillers in low density polyethylene. The distribution and dispersion of the nanoparticles in the LDPE is determined by SEM (Scanning Electron Microscopy). Kinetic studies were carried out by measuring enthalpy, melting temperature, percentage decomposition using simultaneous thermal analyser. Fourier Infrared spectrometer, X-ray diffractometer and dielectric spectrometer are used for characterization and dielectric response. The results are presented and discussed.
关键词： LDPE,Dielectric response,Polyethylene-metal oxide nanocomposite,HVDC cable insulation
更新于2025-09-09 09:28:46
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Sonochemical syntheses of iron doped zinc oxide nanoparticles at different sonication powers and temperatures with their application for photocatalytic degradation of PVC-ZnO composite film
摘要： Doping with iron enhances various properties of zinc oxide making it suitable for several applications. Sonochemical route is an easy way for synthesis of doped ZnO nanoparticles. Input-powers of ultrasound and synthesis–temperature have significant influences over the characteristics of iron-doped zinc oxide nanoparticles. Effects of the varying sonication powers and synthesis temperatures on the average grain size, band gap and magnetic properties of doped ZnO were studied using UV-vis spectrophotometer, X-ray diffraction (XRD), field emission scanning electron micrography (FESEM) with Energy dispersive X-ray spectroscopy (EDX) and SQUID-magnetometer. Both temperature and sonication power influenced the characteristics. The nanoparticles were then used for casting composite films with polyvinyl chloride (PVC) and photodegradation of the film was examined under sunlight. Performances of nanoparticles synthesised at different conditions were compared. Maximum degradation of about 12% was obtained within three hours with nanoparticles synthesised at 42 W power and 30°C temperature.
关键词： sonication-power,temperature,Fe-doped zinc oxide,nanoparticles,photocatalyst,degradation,ultrasound,PVC-nanocomposite,bandgap,magnetization,characterisation
更新于2025-09-05 23:13:11
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Photocatalytic activities using a nanocomposite of mesoporous SiO2 and CdInSe-graphene nanoparticles under visible light irradiation
摘要： The new novel ternary mesoporous SiO2/CdInSe-graphene composites with diameters of approximately 8.08 nm have been fabricated through a self-assembly method. All physical tests demonstrated that the CdInSe-graphene was successfully uniformly distributed onto the surface of the ordered mesoporous silica particles. The obtained mesoporous SiO2/CdInSe-graphene composites exhibited good photocatalytic activity for degradation of both cationic-anionic organic dye groups, as well as the decomposition of the representative phenol group of the compound under visible light irradiation. Moreover, the photocatalytic evolution of hydrogen was studied for establishing a wider application of the as-fabricated SiO2/CdInSe-graphene catalyst in the case of energy conversion. This work indicated that the combination of the mesoporous silica and CdInSe-graphene enables achievements such as an enhancement photocatalytic performance, which has potential in industrial waste management and energy conversion.
关键词： Dye decomposition,CdInSe nanoparticles,Graphene-based nanocomposite,Gallic acid degradation,Mesoporous silica,Hydrogen production
更新于2025-09-04 15:30:14
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Influence of silane coupling agent on the properties of UV curable SiO2-PMMA hybrid nanocomposite
摘要： This work reports the preparation of UV-curable organic–inorganic hybrid nanocomposites synthetized by sol–gel method with the aim of obtaining highly transparent anti-abrasive coatings with long-term storage and stability for the protection of organic light emitting diodes (OLEDs). The inorganic phase is composed of tetraethoxysilane (TEOS) condensed under acid catalysis and mixed with tetrafunctional acrylate monomer and oligomer. Vinyltriethoxysilane (VTES), 3-methacryloxypropyltrimethoxysilane (MEMO), and 3-mercaptopropyltriethoxysilane (MTMO) are used as silane coupling agent and hybrid network modifier. Among the various parameters influencing the structure and properties of the hybrid, this work focuses on the nature and amount of coupling agent and their influence in terms of transparency, mechanical properties, and stability of the formulation. An optimum can be found in the silica to coupling agent ratio. Low level of functionalization leads to hybrids displaying poor optical performances and stability due to the coalescence of silica domains. On the contrary, an excess of functionalization reduces the abrasion resistance and the silica network formation. Changing the organic pendant of coupling agents greatly influences the properties of the coating by promoting the organic–inorganic balance. Dense and flexible as well as mechanically resistant coatings can be obtained from similar formulation by simply tuning the nature of the coupling agent depending of the needs of the application.
关键词： Sol–gel,Abrasion resistance,Nanocomposite,Hybrid coatings,UV-curable
更新于2025-09-04 15:30:14
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Synthesis and characterizations of a novel CoFe2O4@CuS magnetic nanocomposite and investigation of its efficiency for photocatalytic degradation of penicillin G antibiotic in simulated wastewater
摘要： In the present study, efficiency of a new magnetic nanocomposite (CoFe2O4@CuS) for photocatalytic degradation of PG in aqueous solutions was investigated. Structural characteristics of synthesized magnetic nanoparticles were determined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating-sample magnetometer (VSM), Thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET), Energy-dispersive X-ray spectroscopy (EDX) and Raman spectroscopy. Also, the effect of important parameters such as pH (3–11), nanoparticle dosage (0.1-0.8 g/L), PG concentration (10–100 mg/L) and contact time (10–120 min) were investigated. Results of FT-IR, XRD, EDX and Raman analyses showed successful synthesis of CoFe2O4@CuS magnetic nanocomposite. SEM and TEM images showed that the size of CoFe2O4@CuS magnetic nanocomposite was below 100 nm. Also, results of VSM analyses showed that CoFe2O4@CuS magnetic nanocomposite still has magnetic properties (Ms = 7.76 emu/g). According to the results of study, in photocatalytic degradation process of PG by CoFe2O4@CuS magnetic nanocomposite by UV light and in optimum condition (pH = 5, nanocomposite dose: 0.2 g/L, PG concentration: 10 mg/L and contact time: 120 min), maximum degradation of PG was 70.7%. Also the photocatalytic reaction almost followed the pseudo-first order kinetics. In addition, after five consecutive runs, the catalyst efficiency wasn't reduced significantly.
关键词： CoFe2O4@CuS,Magnetic nanocomposite,Penicillin G,Antibiotic
更新于2025-09-04 15:30:14
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Regioselective chemisorption-induced separate deposition of two types of metal nanoparticles on TiO2
摘要： The discovery of the excellent thermal catalytic activity of Au nanoparticles (NPs) for CO oxidation (Haruta et al.,1987 [1]) triggered intensive research on thermal and visible photo-catalysis based on these NPs (Ref. [2]). Recently, catalysts containing two types of metal NPs loaded onto a TiO2 support, i.e., NPs consisting of a separate Au photocatalyst (average size: 13 nm) and another noble metal, were developed as highly efficient visible photocatalysts for several important chemical reactions (Tanaka et al., 2013 [3]). Although the visible photocatalytic activities of Au NPs increase as their particle size decreases (Teranishi et al., 2016 [4]), small Au NPs with a narrow size distribution could not be deposited previously because these NPs underwent dissolution and redeposition (Tanaka et al., 2013 [3]). Additionally, little is known about the mechanism of separate deposition. Herein we report a new method involving the chemisorption and subsequent NaBH4 reduction of Au(III) complex ions on TiO2–Pt. Our method enables the deposition of small Au NPs with a narrow size distribution (average size: 2.5 nm) on the TiO2 surface in TiO2–Pt (Au/TiO2–Pt). The separate deposition was rationalized in terms of the regioselective chemisorption of Au(III) complex ions on the surface of TiO2 by measuring the Au(III) complex ion adsorption.
关键词： Metal complex,Nanocomposite,Regioselective chemisorption,Separate deposition
更新于2025-09-04 15:30:14
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AIP Conference Proceedings [Author(s) PROCEEDINGS OF THE 3RD INTERNATIONAL SYMPOSIUM ON CURRENT PROGRESS IN MATHEMATICS AND SCIENCES 2017 (ISCPMS2017) - Bali, Indonesia (26–27 July 2017)] - Synthesis and photocatalytic activity of nanocomposite based on sodium alginate from brown algae with ZnO impregnation
摘要： The objective of this research is to synthesize nano sodium alginate-ZnO nanocomposite as photocatalyst to degrade methylene blue compounds. The successful synthesis of nano sodium alginate-ZnO nanocomposite was supported by the characterization of XRD (X-Ray Diffraction), FTIR (Fourier Transform Infrared), SEM (Scanning Electron Microscope) and TEM (Tunneling Electron Microscope). The first stage of the research was the synthesis of nano sodium alginate with particle size 140 nm and crystallinity index 38.78 % by XRD and TEM characterization, the obtained particle size was 146 nm x 61 nm. Nano ZnO particle size 38 nm, by XRD and TEM characterization the obtained particle size was 56.6 nm x 33.3 nm. The next stage of nanocomposite synthesis of nano sodium alginate was the impregnation with nano ZnO particle size 130 nm, by XRD and TEM characterization the particle size was 228.0 nm x 134.2 nm. The success was also supported by FTIR and SEM characterization. The final stage was the degradation of blue methylene using nano-sodium alginate-ZnO nanocomposite. The highest degradation percentage by nano sodium alginate-ZnO nanocomposite with zinc nitrate concentration of 0.075 M was 51.68% with the first order rate constant of 9.5 x10-3 /min.
关键词： methylene blue,nano ZnO,degradation,nanocomposite,nano sodium alginate
更新于2025-09-04 15:30:14
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Solution combustion synthesis and characterization of phosphorus doped TiO2–CeO2 nanocomposite for photocatalytic applications
摘要： Phosphorus doped TiO2-CeO2 nanocomposite (P-TiO2-CeO2) was synthesized by solution combustion method. The prepared sample has been heated at di?erent temperatures and characterized by X-ray di?raction (XRD), scanning electron microscopy (SEM), UV–vis absorption spectra, X-ray photoelectron spctroscopy (XPS). XRD analysis reveals the retarded phase transition by increased thermal stability due to phosphorus doping. FE-SEM shows the porous structure of the sample. The absorption edge of the P/TiO2-CeO2 nanocomposite exhibits redshift with increasing heating temperature with its value around 2.93 eV, 2.90 eV and 2.89 eV at 400 °C, 500 °C and 600 °C respectively. From the observed P2p XPS peak, it is con?rmed that the doped phosphorus enters substitutionally into Ce4+/Ti4+ site, which can play an important role in the photocatalytic activity of the sample. The binding energy of Ti 2p XPS peak increases slightly from 458.5 eV to 458.8 eV due to interaction between titanium and cerium.
关键词： Phosphorus doping,TiO2,CeO2,XPS,TiO2-CeO2 nanocomposite
更新于2025-09-04 15:30:14
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Photosynthetic Machineries in Nano-Systems
摘要： Photosynthetic reaction centres are membrane-spanning proteins, found in several classes of autotroph organisms, where a photoinduced charge separation and stabilization takes place with a quantum efficiency close to unity. The protein remains stable and fully functional also when extracted and purified in detergents thereby biotechnological applications are possible, for example, assembling it in nano-structures or in optoelectronic systems. Several types of bio-nanocomposite materials have been assembled by using reaction centres and different carrier matrices for different purposes in the field of light energy conversion (e.g., photovoltaics) or biosensing (e.g., for specific detection of pesticides). In this review we will summarize the current status of knowledge, the kinds of applications available and the difficulties to be overcome in the different applications. We will also show possible research directions for the close future in this specific field.
关键词： Bio-nanocomposite,reaction centre,nanosystems,photosynthesis
更新于2025-09-04 15:30:14
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Carbon nanotube based metal-organic framework nanocomposites: Synthesis and their photocatalytic activity for decolorization of colored wastewater
摘要： Herein, Materials Institute Lavoisier (MIL-125(Ti))/carbon nanotube (CNT) nanoporous composites (MIL/CNT) were synthesized by hydrothermal method. Different amounts of CNT (0.01 g and 0.03 g) were used to synthesize nanocomposites (denoted as MIL/CNT(0.01) and MIL/CNT(0.03), respectively). The synthesized nanomaterials (MIL, MIL/CNT(0.01) and MIL/CNT(0.03)) were characterized by XRD, FTIR, TGA, BET, SEM, and zeta potential and used for photocatalytic dye degradation. Reactive Black 5 (RB5) was used as a model pollutant. The zeta potential of MIL and MIL/CNT (0.01) were ?27.7 mV and 19.2 mV, respectively. The data showed that that MIL/CNT(0.01) nanocomposite had higher photocatalytic dye degradation due to the synergistic effect of CNT. Dye decolorization by the nanomaterials followed the zero-order kinetics reaction. The decolorization rate was 0.0015, 0.0019, 0.0024 mg/L min for MIL, MIL/CNT(0.01) and MIL/CNT(0.03), with the correlation coefficient of 0.9639, 0.9906, and 0.9757, respectively. The synthesized catalysts were reusable over two cycles.
关键词： Metal-organic framework-carbon nanotube nanocomposite,Photocatalytic dye degradation,Reactive Black 5,Synthesis
更新于2025-09-04 15:30:14