Showing 20 results for Nanocomposite
Ali. A. Hosseini,, F. Ghaharpour, H. Rajaei ,
Volume 6, Issue 3 (9-2009)
Abstract
Abstract: In this paper‚ the physical and mechanical properties of Al nanocomposite reinforced with CNTs wereinvestigated. High purity Al powder and Carbon Nanotubes (CNTs) with different percentage were mixed by ballmilling method and the composite was fabricated by cold pressing followed by sintering technique. The variation ofdensity and hardness of composite with CNTcontent was investigated. The microstructure of composite was evaluatedby SEM (Scanning Electron Microscope) and XRD (X -Ray Diffraction). The results show that the density and hardnessincrease with CNTpercentage.
T. Rostamzadeh, H. R. Shahverd,
Volume 8, Issue 1 (3-2011)
Abstract
Abstract: In this study Al-5 (Vol) % SiCp nanocomposite powder has been successfully synthesized by high-energy planetary milling of Al and SiC powders for a period of 25 h at a ball-to-powder ratio of 15:1. The changes of the lattice strain, the crystallite size of the matrix phase, and the nanocomposite powder microstructure with time have been investigated by X-ray diffraction (XRD), X-ray mapping, and scanning electron microscopy (SEM) analyses. The morphologies of the nanocomposite powders obtained after 25 h of milling have also been studied by transmission electron microscopy (TEM). The results showed that nanocomposite powders were composed of near-spherical particles and, moreover, the SiC particles were uniformly distributed in the aluminum matrix.
M. Kadkhodaee, H. Daneshmanesh, B. Hashemi, J. Moradgholi,
Volume 11, Issue 1 (3-2014)
Abstract
Accumulative roll-bonding process (ARB) is an important severe plastic deformation technique for production of the ultrafine grained, nanostructured and nanocomposite materials in the form of plates and sheets. In the present work, this process used for manufacturing Al/SiO 2 nanocomposites by using Aluminum 1050 alloy sheets and nano sized SiO 2 particles, at ambient temperature. After 8 cycles of ARB process, the tribological properties and wear resistance of produced nanocomposites were investigated. The wear tests by abrasion were performed in a pinon-disc tribometer. Results show that by increasing ARB cycles and the amount of nano powders, the friction coefficient of produced nanocomposites decreases.
M. M. Mohammadi Samani, H. R. Baharvandi, H. Abdizadeh, J. Rezapour,
Volume 11, Issue 4 (12-2014)
Abstract
B4C and its composites with TiB2 as second phase continues to be extensively used as the preferred ceramic material in military applications as armor systems for absorbing and dissipating kinetic energy from high velocity projectiles. It also exhibits a high melting point (2427 °C), and high neutron absorption cross section. Pressureless sintering of the B 4C-nanoTiB2 nanocomposite using small amount of Fe and Ni (≤3 Wt%) as sintering aids was investigated in order to clarify the role of Fe and Ni additions on the mechanical and microstructural properties of B4C-nanoTiB2 nanocomposites. Different amount of Fe and Ni, mainly 1 to 3 Wt% were added to the base material. Pressureless sintering was conducted at 2175, 2225 and 2300 °C. It was found that Addition of 3 Wt% Fe and 3 wt% Ni and sintering at 2300 °C resulted in improving the density of the samples to about 99% of theoretical density. The nanocomposite samples exhibited high density, hardness, and microstructural uniformity.
N. Bahrami Panah, N. Ajami,
Volume 13, Issue 1 (3-2016)
Abstract
The epoxy coatings containing multi-walled carbon nanotube/ poly ortho aminophenol nanocomposite were prepared and used as anticorrosive coatings. The nanocomposites with different contents of carbon nanotube were synthesized in a solution of sodium dodecyl sulfate and ammonium peroxy disulfate as a surfactant and an oxidant, respectively. The morphology and structural properties were confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy methods. The mean size of nanocomposite particles was 20-35 nm determined by scanning electron microscopy. The epoxy coatings containing the nanocomposites were applied over mild steel panels and their corrosion performance was investigated using electrochemical impedance spectroscopy and potentiodynamic polarization measurements in a 3.5 % sodium chloride solution. The results showed that epoxy coatings consisting of nanocomposite with 1 wt.% multi-walled carbon nanotube exhibited higher anticorrosive properties than other prepared coatings of different carbon nanotube contents, which could be due to the strong interaction between the mild steel surface and the conjugated nanocomposite.
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M. S. Mahmoudi Jozee, S. Sanjabi, O. Mirzaee,
Volume 13, Issue 3 (9-2016)
Abstract
A homogenous TiO2 / multi-walled carbon nanotubes(MWCNTs) composite film were prepared by electrophoretic co-deposition from organic suspension on a stainless steel substrate. In this study, MWCNTs was incorporated to the coating because of their long structure and their capability to be functionalized by different inorganic groups on the surface. FTIR spectroscopy showed the existence of carboxylic groups on the modified carbon nanotubes surface. The effect of applied electrical fields, deposition time and concentration of nanoparticulates on coatings morphology were investigated by scanning electron microscopy. It was found that combination of MWCNTs within TiO2 matrix eliminating micro cracks presented on TiO2 coating. Also, by increasing the deposition voltages, micro cracks were increased. SEM observation of the coatings revealed that TiO2/multi-walled carbon nanotubes coatings produced from optimized electric field was uniform and had good adhesive to the substrate.
F. Sakhaei, E. Salahi, M. Eolya, I. Mobasherpour,
Volume 13, Issue 4 (12-2016)
Abstract
Up to now, lots of materials such as active carbon, iron, manganese, zirconium, and metal oxides have been widely used for removal of dyes from contaminated water. Among these, ferrite nanoparticle is an interesting magnetic material due to its moderate saturation magnetization, excellent chemical stability and mechanical hardness. Graphene, a new class of 2D carbonaceous material with atom thick layer features, has attracted much attention recently due to its high specific surface area. Reduced graphene oxide (rGO) has also been of great interest because of its unique properties, which are similar to those of graphene, such as specific surface area, making it an ideal candidate for dye removal. Thus far, few works have been carried out on the preparation of CoFe2O4-rGO composite and its applications in removal of contaminants from water. In this paper, CoFe2O4 reduced graphene oxide nanocomposite was fabricated using hydrothermal process. During the hydrothermal process, the reduction of graphene oxide and growth of CoFe2O4 simultaneously occurred on the carbon basal planes under the conditions generated in the hydrothermal system. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy contaminant and UV-Vis spectroscopy as the analytical method. The experimental results suggest that this material has great potential for treating Congo red contaminated water.
R. Hasanzadeh, T. Azdast, R. Eungkee Lee, A. Afsari Ghazi,
Volume 14, Issue 3 (9-2017)
Abstract
Material selection is a main purpose in design process and plays an important role in desired performance of the products for diverse engineering applications. In order to solve material selection problem, multi criteria decision making (MCDM) methods can be used as an applicable tool. Bumper beam is one of the most important components of bumper system in absorbing energy. Therefore, selecting the best material that has the highest degree of satisfaction is necessary. In the present study, six polymeric nanocomposite materials were injection molded and considered as material alternatives. Criteria weighting was carried out through analytical hierarchy process (AHP) and Entropy methods. Selecting the most appropriate material was applied using technique for order preference by similarity to ideal solution (TOPSIS) and the multi-objective optimization on the basis of ratio analysis (MOORA) methods respect to the considered criteria. Criteria weighting results illustrated that impact and tensile strengths are the most important criteria using AHP and Entropy methods, respectively. Results of ranking alternatives indicated that polycarbonate containing 0.5 wt% nano Al2O3 is the most appropriate material for automotive bumper beam due to its high impact and tensile strengths in addition to its low cost of raw material. Also, the sensitivity analysis was performed to verify the selection criteria and the results as well.
Z. Abasali Karaj Abad, A. Nemati, A. Malek Khachatourian, M. Golmohammad,
Volume 17, Issue 4 (12-2020)
Abstract
The graphene oxide -TiO2 (GO-TiO2) and pre-reduced graphene oxide -TiO2 (rGO-TiO2) nanocomposites were fabricated successfully by hydrothermal method. The microstructure of synthesized nanocomposites was investigated using field emission scanning electron microscopy (FESEM) equipped with energy dispersive spectroscopy (EDS) analysis. Moreover, galvanostatic charge/discharge (GCD), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) methods in three electrode system were applied to evaluate electrochemical properties. The results revealed that nanoparticles distributed more uniformly on graphene sheets, at lower concentrations of TiO2. The rGO-TiO2 and GO-TiO2 nanocomposites showed 224 and 32 F/g specific capacitance at 5 mV s-1 scan rate in 1 M KOH aqueous electrolyte, respectively. The pre-reduction of graphene oxide is the main reason for the better electrochemical performance of rGO-TiO2 nanocomposite compared to GO-TiO2 nanocomposite.
Amirhosein Paryab, Toktam Godary, Sorosh Abdollahi, Mohsen Anousheh, Adrine Malek Khachatourian,
Volume 18, Issue 3 (9-2021)
Abstract
Silicon oxycarbide (SiOC) materials derived from silicone attracted great attention for their superior high-temperature behavior. In the present study, Si(Ti)OC and Si(Ti,Al)OC nanocomposites, in which alkoxide precursors were used with the main silicone precursor, have been compared with SiOC material. Although in SiOC, C was bonded with Si in a carbon-rich SiOC phase, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) showed that TiC was the preferred state for C atoms upon adding Ti into the system. This claim was also substantiated by Raman spectroscopy, where adding Ti into the system lowered the intensity of the D band, indicating the high affinity of C to form crystalline TiC. In the Si(Ti,Al)OC nanocomposites synthesized by adding AlCl3 into the Si(Ti)OC system, mullite nanocrystals formed a superlattice structure with TiC. UV-vis spectra of the nanocomposites showed Si(Ti,Al)OC with mullite-TiC superlattice had a larger bandgap compared with Si(Ti)OC with only TiC nanocrystals.
Saba Payrazm, Saeid Baghshahi, Zahra Sadeghian, Amirtaymour Aliabadizadeh,
Volume 19, Issue 3 (9-2022)
Abstract
In this research, zinc oxide quantum dots and graphene nanocomposites were synthesized via two different methods; In the first (direct) method, ZnO-graphene Nanocomposites were made mixing the synthesized zinc oxide and graphene. In the second (indirect) method, zinc nitrate, graphene, and sodium hydroxide were used to made ZnO-graphene Nanocomposites. XRD, FTIR and Raman spectroscopy analyses were used for phase and structural evaluations. The morphology of the nanocomposites w::as char::acterized by SEM. The specific surface area and porosity of the samples were characterized by BET analysis. The optical properties of the samples were investigated by photoluminescence and ultraviolet-visible spectroscopy analyses. Results showed that using graphene, increased the photoluminescence property and shifted the photoluminescence spectrum of the composites towards the visible light spectrum. The photoluminescence of the synthesized graphene-zinc oxide composite, in the visible light region, was closer to white light than that of pure zinc oxide. According to the results of BET test, the nanocomposite synthesized by direct method had a higher surface area (25.7 m2.g-1) and a higher porosity (0.32 cm3.g-1) than the nanocomposite synthesized by the indirect method with a specific surface area of (16.5 m2.g-1) and a porosity of 0.23 cm3.g-1).
Mohammad Roostaei, Hossein Aghajani, Majid Abbasi, Behzad Abasht,
Volume 19, Issue 3 (9-2022)
Abstract
This study investigates the synthesis of Al/MoS2 nanocomposite coating by the electro spark deposition (ESD) method for its lubricating properties. ESD method was selected because it is a very easy, rapid, and cost-saving method and the resulting coating has a strong bonding with the substrate. As a substrate, a Ti-6Al-4V alloy sheet containing 6.12 % Al, 4.06 % V, 0.19% Fe, and 0.05 % Ni was used. For coating, an aluminum-molybdenum disulfide composite electrode in the form of a cylindrical rod was employed. Three frequencies of 5, 8, and 11 kHz, three current limits of 15, 25, and 35 amps, and three duty cycles of 50, 60, and 70% were used in the coating operation. AFM analysis was used to study the topography, morphology, and calculate roughness. The samples were then subjected to hardness tests. To determine the wear resistance of the samples, pin on disk tests were performed. XRD analysis was performed to identify the phases on the surface of the coated samples. SEM was used to examine the microstructure of the coating before and after wear testing, in order to determine the wear mechanism. The results indicated that the Al/MoS2 nanocomposite coating was synthesized on the substrate surface. The hardness of the reference sample is 353 Vickers, and that of the coated samples is about 200 Vickers. For the reference sample, the roughness was measured at 15.7 nm, and for the coated sample at 268.1 nm. As spark energy increased, the coefficient of friction increased by approximately 0.09. As spark energy increased, the wear rate increased by 27%. A significant increase in the Lancaster coefficient occurred around 5 joules of energy. According to the wear rate results, the sample with the lowest thickness wears 4% less than the sample with the highest thickness. The wear rate of sample 351170 is 78% lower than that of sample 150550.
Zainab J. Shanan, Huda M.j. Ali, H.f. Al-Taay,
Volume 19, Issue 3 (9-2022)
Abstract
The objectives of this work is to synthesize TiO2/MgO nanocomposites using a pulse laser deposition technique. At a vacuum pressure of 2.5 10-2 mBar, TiO2/MgO nanocomposites were synthesized on substrates with a laser power of 600 mJ and a wavelength of 1064 nm. This search utilizes various pulses (500, 600, and 700) at a 6-Hertz repetition rate. X-ray diffraction was utilized to investigate crystallography of the phases in the samples, as well as average crystallite size (XRD). An increase in the average crystal size was observed with an increase in the number of shots (from 35.15 to 38.08) nm at (500 to 700) shots respectively. The impact of the number of laser shots on the surface characteristics of TiO2/MgO nanocomposites was also evaluated using atomic force microscopy (AFM) and field emission scanning electron microscopy (FE-SEM). Finally, optical characteristics were evaluated using UV-Vis spectroscopy. Increasing the number of shots increased the absorbance and thus reduced the energy gap.
Sreedevi Gogula, Sandhya Cole, Venkata Rao Kanakala, Gogula Jaya Ram Pavan Kumar, B Tirumala Rao,
Volume 19, Issue 4 (12-2022)
Abstract
The present study used a hydrothermal technique to synthesize undoped and Mn2+ doped CdS/Zn3(PO4)2 semiconducting nanocomposite materials. Powder X-ray diffraction, scanning electron microscopy, UV-Vis diffuse reflectance spectrometer, Fourier transform-Infrared Spectroscopy-FT-IR, and photoluminescence techniques were employed to study structural, optical, and luminescence properties of produced nanocomposites. The hexagonal structure of CdS and the monoclinic structure of Zn3(PO4)2 are both reflected in the powder X-ray diffraction spectra. When Mn2+ ions are present in the host lattice, a lattice distortion occurs, causing a phase change from the phase of γ-Zn3(PO4)2 to the β-phase of Zn3(PO4)2, without affecting the hexagonal phase of CdS. The average crystallite size of produced nanocomposites was 22-25 nm, and also calculated the lattice strain and dislocation density to better understand internal deformation of the samples. The FT-IR spectra were used to investigate the molecular vibrations and functional groups in the samples. The surface morphology of the nanocomposites is hexagonal spheres on rectangular shaped nano-flakes, and the interatomic distance between the hexagonal spheres is decreased as the doping concentration increases, forming a rod-like structure on the flakes. EDAX results confirm the presence of various relevant elements in the prepared samples. The quantum confinement of produced samples reduces as the Mn2+ doping concentration in the host lattice increases. The photoluminescence results demonstrate shallow trapped states due to the transition: d-d (4T1 → 6A1) of the tetrahedrally coordinated Mn2+ states and the impact of Mn2+ ions exhibiting several peaks in the UV-Visible region (365-634 nm) generating RGB (Red, Green, Blue) luminescence. Color coordinates and CCT values were calculated using the CIE diagram, and color correlated temperatures in the range of 2513–7307 K were discovered, which might be used in solid state lighting applications.
Behzad Rahimzadeh, Maisam Jalaly, Mehrdad Roshan,
Volume 20, Issue 1 (3-2023)
Abstract
Considering the widespread use of aluminum composites in various industries and the emergence of nanomaterials such as graphene and boron nitrite (BN) with their unique properties, aluminum-based nanocomposite reinforced by the graphene-BN hybrid was fabricated at different percentages. For this purpose, the graphene-BN hybrid was prepared and subjected to wet milling along with the aluminum powder. The mechanical properties of the final nanocomposite which was consolidated using the spark plasma sintering (SPS) method were examined. Aluminum-based composite specimens containing 1 wt.% graphene–0 wt.% BN (AGB1), 0.95 wt.% graphene–0.05 wt.% BN (AGB2), 0.90 wt.% graphene–0.1 wt.% BN (AGB3), and 0.85 wt.% graphene–0.15 wt.% BN (AGB4) were fabricated and compared with non-reinforced aluminum (AGB0). The hardness values of 48.1, 51.1, 56.2, 54.1, and 43.6 Hv were obtained for AGB0, AGB1, AGB2, AGB3, and AGB4, respectively. Additionally, tensile strengths of these specimens were 67.2, 102.1, 129.5, 123.7, and 114.7 MPa, respectively. According to the results of the hardness and tensile tests, it was revealed that the AGB2 specimen had the highest tensile strength (93% higher than AGB0 and 27% higher than AGB1) and hardness (17% higher than AGB0 and 10% higher than AGB1).
Saeedeh Mansoury, Maisam Jalaly, Mohammad Khalesi Hamedani,
Volume 20, Issue 4 (12-2023)
Abstract
In this study, an epoxy-based nanocomposite reinforced with copper oxide-graphene oxide hybrid was investigated. Initially, the hybrid powder of CuO–GO with a weight ratio of 9:1 was prepared. The hybrid filler with different weight percentages ranging from 0.1–0.5 was used to reinforce the epoxy resin. The prepared samples were analyzed using XRD, FTIR, FESEM, TEM, and tensile testing. According to the XRD results and SEM images, the hybrid powder was successfully prepared, and the mechanical testing results showed an improvement in tensile strength in the composite samples. The best composite sample in terms of tensile strength was the one containing 0.3 wt% of hybrid reinforcement, which exhibited a 73% increase in strength compared to the neat resin sample.
Pravin Jadhav, R.s.n Sahai, Deepankar Biswas, Asit Samui,
Volume 20, Issue 4 (12-2023)
Abstract
The present work deals with the effect of Multi-walled Carbon Nanotube (MWCNT) and functionalized (carboxyl and amine) MWCNT on the mechanical properties of the PAEK (Poly Aryl Ether Ketone) polymer composite. The MWCNT and functionalized (carboxyl and amine) MWCNT concentration varied as 0.25, 0.5 and 0.75 weight percentages. Compositeswere prepared by using a melt compounding method using a twin-screw extruder and all testing samples were prepared using an injection molding machine as per American Society for Testing and Materials (ASTM) standards. Samples were tested for tensile strength, impact strength, flexural strength, heat deflection temperature, hardness, and density. There is an increase in the tensile strength, impact strength, flexural strength, and heat deflection temperature, with percentage increase in filler loading up to 0.5 %, followed by decrease in it with higher filler loading. The increase is maximum for amine functionalized MWCNT.
Muhammad Shahzad Sadiq, Muhammad Imran, Abdur Rafai, Muhammad Rizwan,
Volume 21, Issue 2 (6-2024)
Abstract
With increasing energy demand and depletion of fossil fuel resources, it is pertinent to explore the renewable and eco-friendly energy resource to meet global energy demand. Recently, perovskite solar cells (PSCs) have emerged as plausible candidates in the field of photovoltaics and considered as potential contender of silicon solar cells in the photovoltaic market owing to their superior optoelectronic properties, low-cost and high absorption coefficients. Despite intensive research, PSCs still suffer from efficiency, stability, and reproducibility issues. To address the concern, the charge transport material (CTM) particularly the electron transport materials (ETM) can play significant role in the development of efficient and stable perovskite devices. In the proposed research, we synthesized GO-Ag-TiO2 ternary nanocomposite by facile hydrothermal approach as a potential electron transport layer (ETL) in a regular planar configuration-based PSC. The as synthesized sample was examined for morphological, structural, and optical properties using XRD, and UV-Vis spectroscopic techniques. XRD analysis confirmed the high crystallinity of prepared sample with no peak of impurity. The optimized GO-Ag-TiO2 ETL exhibited superior PCE of 8.72% with Jsc of 14.98 mA.cm-2 ,Voc of 0.99 V, and a fill factor of 58.83%. Furthermore, the efficiency enhancement in comparison with reference device is observed which confirms the potential role of doped materials in enhancing photovoltaic performance by facilitating efficient charge transport and reduced recombination. Our research suggests a facile route to synthesize a low-cost ETM beneficial for the commercialization of future perovskite devices.
Satish Ahire, Ashwini Bachhav, Bapu Jagdale, Thansing Pawar, Prashant Koli, Dnyaneshwar Sanap, Arun Patil,
Volume 21, Issue 2 (6-2024)
Abstract
Hybrid photocatalysts, comprising both inorganic and organic polymeric components, are the most promising photocatalysts for the degradation of organic contaminants. The nanocomposite, Titania-Polyaniline (TiO2-PANI) was synthesized using the chemical oxidative polymerization method. Various characterization techniques were employed to assess the properties of the catalysts. The ultraviolet diffuse reflectance spectroscopy (UV-DRS) analysis revealed that the TiO2 absorbs only UV light while the TiO2-PANI nanocomposite absorbs light from both UV and visible regions. The X-ray diffraction (XRD) results confirmed the presence of TiO2 (anatase) in both TiO2 nanoparticles and TiO2-PANI (Titania-Polyaniline) nanocomposite. The phases of the catalysts were verified through Raman, TEM, and SAED techniques where all results are in good agreement with each other. The average crystallite size of TiO2 nanoparticle and TiO2-PANI nanocomposite were 13.87 and 10.76 nm. The thermal stability of the catalysts was assessed by the Thermal gravimetric analysis (TGA) technique. The order of the thermal stability is TiO2 > TiO2-PANI > PANI. The crystal lattice characteristics were confirmed using Transmission electron microscopy (TEM). The surface area measurements were confirmed from the Brunauer-Emmett-Teller (BET) study and were employed for the evaluation of the photocatalytic efficiency of both, TiO2 nanoparticles and TiO2-PANI nanocomposite catalysts. The energy dispersive spectroscopy (EDS) study was employed for elemental detection of the fabricated materials. While Raman spectroscopy was employed for the chemical structure and the phase characteristics of the materials. The standard conditions for the degradation of the CF dye were 8 g/L of catalyst dosage, 20 mg/L of dye concentration, and a pH of 7. The TiO2-PANI nanocomposite exhibited superior efficiency as compared to pure TiO2 nanoparticles, achieving almost 100 % degradation in just 40 minutes.
Wed Abed,
Volume 21, Issue 2 (6-2024)
Abstract