Nano-sized Morphology Research Articles

Synthesis and tribological assessment of oil-based nanolubricants blended with nano-zeolite for steel–steel contact

This study aims to synthesize zeolite with nano-sized morphology and investigate the tribological performance of nano-zeolite as a lubricating additive dispersed in an oil-based lubricant. Tribological tests were performed and morphologies of wear tracks were characterized to investigate the friction reduction and anti-wear properties of zeolite, respectively. The lubrication mechanism was discussed by illustrating the effects of concentration and particle size on the tribological behavior of zeolite. The optimal concentration of nano-zeolite to improve the tribological performance of the base oil was 2 wt.%, which exhibited a friction reduction of 34.3%. Zeolite particles with larger diameters showed better dispersion stability but worse lubrication performance, which could be concluded from the decrease in the friction reduction ratio. Moreover, the friction coefficient under the lubrication of zeolite at 200°C was 15.8% lower than that of the pure base oil, demonstrating the thermal stability of zeolite. Notably, the application of zeolite resulted in an increase in wear depth due to the occurrence of the three-body abrasion, while the surface asperities of the counterpart were also smoothed in the meantime. This work demonstrates the potential of nano-zeolite to enhance the tribological performance of oil-based lubricants in industrial applications, which could be attributed to their porous structure, lipophilicity, and chemical–thermal stability.

Exploring the potential of reduced graphene oxide/polyaniline (rGO@PANI) nanocomposites for high-performance supercapacitor application

This study introduces a facile synthesis method for synthesizing reduced graphene oxide (rGO) nanosheets with surface decoration of polyaniline (PANI). The resultant rGO@PANI nanocomposite (NC) exhibit substantial potential as advanced electrode materials for high-performance supercapacitors. The strategic integration of PANI onto the rGO surface serves dual purposes, effectively mitigating agglomeration of rGO films and augmenting their utility in supercapacitor applications. The PANI coating manifests a highly porous and nanosized morphology, fostering increased surface area and optimized mass transport by reducing diffusion kinetics. The nanosized structure of PANI contributes to the maximization of active sites, thereby bolstering the efficacy of the nanocomposites for diverse applications. The inherent conductive nature of the rGO surface significantly expedites electron transport, thereby amplifying the overall electrochemical performance of the nanocomposites. To systematically evaluate the influence of PANI concentration on the electrode performance, varying concentrations of PANI were incorporated. Notably, an elevated PANI concentration was found to enhance the response owing to the unique morphology of PANI. Remarkably, the 5 % rGO@PANI NC emerged as the most promising candidate, demonstrating exceptional response characteristics with a specific capacitance of 314.2 F/g at a current density of 1 A/g. Furthermore, this catalyst exhibits outstanding long-term stability, retaining approximately 92 % of its capacitance even after enduring 4000 cycles. This research underscores the significance of the synergistic integration of rGO and PANI in the design of high-performance supercapacitors. The elucidation of the underlying mechanisms governing the improved electrochemical properties contributes to the fundamental understanding of nanocomposite behavior, thereby paving the way for the rational design of next-generation energy storage materials.

Preparation of ultra-sensitive and highly specific miniature hydrogen sensors by <i>in situ</i> synthesis methods

Hydrogen, as one of the most well-developed green energy materials, has played an important role in industrial development, human production and life, and the treatment of diseases in recent years. Hydrogen sensor is an important safety monitoring equipment in chemical production. Developing long-term and efficient hydrogen gas sensor for real-time monitoring has become increasingly important and urgent. Hydrogen, as one of the main combustible gases present in the petrochemical production process, is of great research significance and challenging in meeting the need of cycling gas identification and highly sensitive detection. Therefore, it is of great practical value to develop the low-cost, low-power and highly sensitive miniature hydrogen gas sensors . In this work, a gold-doped tin dioxide nanostructured ultra-sensitive and highly specific micro-nanosensor is obtained based on the in-situ synthesis of micro-hot plates. It is shown that the sensitivity of this nanosensor is as high as 100 for hydrogen at 50 ppm, and the sensitivity of ethanol, an important interference gas, is only 1/22 of that of hydrogen at the same concentration, which has an obvious suppression effect. For the same concentration of carbon monoxide, methane and other interference gases do not show any response. XPS characterization shows that the defective oxygen ratio of the material is the main reason for the ultra-sensitivity of the sensor. Meanwhile, in this study, the precursor solution of gold-doped tin dioxide is prepared by using chloroauric acid and tin tetrachloride crystals as raw materials; the nanosized morphology structure is prepared by templating the generation of sensitive materials using polystyrene microspheres; the in-situ synthesis method is realized by applying a voltage to the calcination of a micro hot plate. Through this nanoscale templating in-situ heating method, a gold-loaded tin dioxide nanosensor is prepared. Note that the template assisted in-situ grown <inline-formula><tex-math id="M5">\begin{document}$ {\mathrm{A}}{\mathrm{u}} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M5.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M5.png"/></alternatives></inline-formula> loaded Tin Oxide nano sensor is abbreviated as <inline-formula><tex-math id="M6">\begin{document}$ {\mathrm{T}}{\mathrm{I}}{\mathrm{S}}\text{-}{\mathrm{Au}}\text{-}{{\mathrm{S}}{\mathrm{n}}{\mathrm{O}}}_{2} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M6.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M6.png"/></alternatives></inline-formula> Sensor . In order to illustrate the sensing mechanism, we analyze the elemental compositions, and the results show that under the condition of the high defective oxygen content, the in-situ heating method of templated preparation of <inline-formula><tex-math id="M7">\begin{document}$ {\mathrm{A}}{\mathrm{u}}\text{-}{{\mathrm{S}}{\mathrm{n}}{\mathrm{O}}}_{2} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M7.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="2-20231265_M7.png"/></alternatives></inline-formula> nano-sensor containing arrays of polystyrene spheres becomes an important reason for the ultra-sensitivity to hydrogen, high specificity, and the suppression of the important interfering gas, ethanol. Moreover, the in situ preparation method can be flexibly and scalably used to prepare high-performance miniaturized gas sensors with a variety of hollow-sphere nanostructured metal oxides, in order to obtain excellent sensitivity and adjustable selectivity.

In-situ synthesis of dual functionalized MOF by engineering modulator induced defect for efficient remediation of aqueous mercury through adsorption

UiO-66 is an extremely versatile metal organic framework (MOF) due to its remarkable water stability and high specific surface area. The incorporation of modified chemical and structural defects (missing linker and missing cluster defects) into the crystalline UiO-66 by the simultaneous use of an amino modified ligand and a thiol containing monocarboxylic acid modulator (thioglycolic acid, TGA) during synthesis resulted in developing a novel dual-functional MOF, designated as NH2-UiO-66-SH_C. This material was characterized using FTIR, XRD, FESEM, EDX, XPS, BET and Zetasizer to explore the morphological integrity and chemical composition. NH2-UiO-66-SH_C crystals demonstrated irregular nano-sized morphology (< 100 nm) and microporous nature with specific surface area of 519.6 m2/g. The material was subsequently tested to adsorb the highly toxic aqueous mercury (Hg) which is responsible for severe damages to human health. The maximum adsorptive capacity for aqueous inorganic mercury was 885 mg/g at 303 K. The optimum adsorbent dose and solution pH were 0.3 g/L and 5, respectively. The adsorption was endothermic and followed pseudo-second order kinetics. The developed nano-adsorbent illustrated enhanced sorption capacities which were far higher compared to its parent MOFs (UiO-66 as well as NH2-UiO-66) and other reported modified forms of UiO-MOFs. A regeneration method that was effective over 5 cycles (Hg removal efficiency > 90%) was also reported. Overall, this study reports the development of a newly modified nano-crystalline MOF, by manipulation of the synthetic chemistry (with defect modulation), which is a promising adsorbent for Hg (II) in aqueous phase.

Designing mordenite zeolites with tunable distribution of acid sites in channels and nano-morphology to boost the catalytic behavior performance of dimethyl ether carbonylation

Mordenite (MOR) zeolite is an efficient catalyst for dimethyl ether (DME) carbonylation, which a key step of indirect production of ethanol from syngas. Herein, a nanosheets MOR zeolite with an ultrathin thickness of 10–30 nm can be facilely synthesized by using a commercial cetyltrimethylammonium hydroxide agent. It greatly shortened the pore length of 8-membered ring (8-MR) side pocket and more amount of Brønsted acid sites (BAS) can be exposed. More importantly, the amount of BAS in 8-MR side pockets of the MOR zeolite can be significantly increased. It should be noted that the morphology of MOR zeolite with prismatic, nanosheets, and petal-like can be obtained and precisely regulated. As a result, the conversion of DME over the nanosheets MOR zeolite is increased by nearly 2 times. Our finding proposed a novel strategy for constructing tunable nanosized morphology MOR zeolite and simultaneously directional enrichment of BAS in 8-MR channels.

Fabrication of amorphous metal-organic framework in deep eutectic solvent for boosted organophosphorus pesticide adsorption

Herein, we describe a new and sustainable strategy of directly constructing the amorphous metal-organic framework (MOF) through the use of deep eutectic solvent (DES) for the highly effective and efficient adsorption of organophosphorus pesticide from contaminated water. The as-obtained products possessed nanosize morphology (as small as 40 nm), hierarchical pores ranging from 1.16 to 12.3 nm, high porosity up to 0.5954 cm3 g−1, and abundant unsaturated metal centers. The presence of structural disorder increased the number of active sites and promoted the diffusion of target molecules, leading to enhance host-guest interactions. These properties were beneficial for the application of the material in the enrichment adsorption of profenofos. The amorphous UiO-66 with the highest content of defect disorder (4.408) displayed a remarkably high affinity toward profenofos, resulting in an exceptional adsorbate uptake capacity over 1300 mg·g−1. This is a three-fold enhancement compared to its crystalline counterpart. And its performance surpassed that of most previously reported absorbents. Additionally, the adsorption behavior and mechanism of amorphous UiO-66 toward profenofos were elucidated by high-revolution X-ray photoelectron spectroscopy (XPS) and various models. The results revealed a multi-layer heterogeneous adsorption, involving multiple sorption process. The profenofos adsorption mechanisms over amorphous UiO-66 mainly rely on hydrogen bonding, Zr-O-P bonds, and P-Zr bonds. Moreover, the amorphous UiO-66 exhibited outstanding regeneration and reusability characteristics, making it a stable and promising adsorbent for water remediation. Its efficient and rapid removal of pollutants holds great potential for practical applications, while also providing guidelines for the design and optimization of next-generation sorbent.

Inflammation-responsive nanoparticles suppress lymphatic clearance for prolonged arthritis therapy.

The clearance of nanomedicine in inflamed joints has been accelerated due to the increased lymph angiogenesis and lymph flow in arthritic sites. To maximize the therapeutic efficacy for rheumatoid arthritis (RA), it is necessary to facilitate targeted delivery and extended drug retention in inflamed synovium simultaneously. In general, nanosized particles are more likely to achieve prolonged circulation and targeted delivery. While drug carriers with larger dimension might be more beneficial for extending drug retention. To balance the conflicting requirements, an inflammation-responsive shape transformable nanoparticle, comprised of amyloid β-derived KLVFF peptide and polysialic acid (PSA), coupled with therapeutic agent dexamethasone (Dex) via an acid-sensitive linker, was fabricated and termed as Dex-KLVFF-PSA (DKPNPs). Under physiological condition, DKPNPs can keep stable nanosized morphology, and PSA shell could endow DKPNPs with long circulation and active targeting to arthritic sites. While in inflamed joints, acidic pH-triggered Dex dissociation or macrophages-induced specific binding with PSA would induce the re-assembly of DKPNPs from nanoparticles to nanofibers. Our results reveal that intravenously injected DKPNPs display prolonged in vivo circulation and preferential distribution in inflamed joints, where DKPNPs undergo shape transition to fibrous structures, leading to declined lymphatic clearance and prolonged efficacy. Overall, our dual-stimulus responsive transformable nanoparticle offers an intelligent solution to achieve enhanced therapeutic efficacy in RA.

Reitveld refinement, structural, optical band gap and low-temperature magnetic characterization of Gd3+ doped spinel cubic CoFe2O4 nanoparticles

The current study unravels the structural, optical band gap and magnetic characteristics of rare-earth (RE) gadolinium (Gd) substituted CoGdxFe2-xO4 (x= 0.00 - 0.10, in the interval of 0.02) nanocrystallites synthesized by the sol-gel self-ignition route. The XRD analysis and Rietveld refinement confirmed the existence of a single cubic phase with a crystallite size of ~15-21 nm range, further confirmed by HRTEM results. SEM images confirmed the well-known nano-size morphology for all the samples. The magnetization measurements show a hard ferromagnetic nature for all specimens within the temperature range of 20-300K. Coercivity, remanent, and saturation magnetization monotonically increased with a reduction in temperature from 300K to 20K. UV-Vis absorbance results show that the band gap energy of CoFe2O4 nanoparticles (NPs) decreases with increasing Gd3+ ion doping and have band gap energy values of 2.47, 2.15, 2,02, 2.00, 1.43 and 1.95 eV for x= 0.00, 0.02, 0.04, 0.06, 0.08, 0.10, respectively in CoGdxFe2-xO4 nanoferrites. The present study reveals that structural, optical band gap and magnetic properties could be altered by monitoring the quantity of gadolinium in cobalt nanoferrites.&#x0D; Bangladesh J. Sci. Ind. Res. 57(3), 173-186, 2022

Reticular Synthesis of Hydrogen-Bonded Organic Frameworks and Their Derivatives via Mechanochemistry.

Rational synthesis of hydrogen-bonded organic frameworks (HOFs) with predicted structure has been a long-term challenge. Herein, by using the efficient, simple, low-cost, and scalable mechanosynthesis, we demonstrate that reticular chemistry is applicable to HOF assemblies based on building blocks with different geometry, connectivity, and functionality. The obtained crystalline HOFs show uniform nano-sized morphology, which is challenging or unachievable for conventional solution-based methods. Furthermore, the one-pot mechanosynthesis generated a series of Pd@HOF composites with noticeably different CO oxidation activities. In situ DRIFTS studies indicate that the most efficient composite, counterintuitively, shows the weakest CO affinity to Pd sites while the strongest CO affinity to HOF matrix, revealing the vital role of porous matrix to the catalytic performance. This work paves a new avenue for rational synthesis of HOF and HOF-based composites for broad application potential.

Fe3O4/Graphene Composite Anode Material for Fast-Charging Li-Ion Batteries.

Composite anode material based on Fe3O4 and reduced graphene oxide is prepared by base-catalysed co-precipitation and sonochemical dispersion. Structural and morphological characterizations demonstrate an effective and homogeneous embedding of Fe3O4 nanoparticles in the carbonaceous matrix. Electrochemical characterization highlights specific capacities higher than 1000 mAh g−1 at 1C, while a capacity of 980 mAhg−1 is retained at 4C, with outstanding cycling stability. These results demonstrate a synergistic effect by nanosize morphology of Fe3O4 and inter-particle conductivity of graphene nanosheets, which also contribute to enhancing the mechanical and cycling stability of the electrode. The outstanding capacity delivered at high rates suggests a possible application of the anode material for high-power systems.

On the role of failure analysis investigations in alloy development illustrated with case study involving Ni-Mo alloy

During thermo-mechanical processing of a Ni-Mo alloy, three hot-rolled slabs at 1250 °C have been stacked on top of each other during air-cooling. Upon reaching ambient temperature, the middle slab is found to develop a mid-length transverse crack running through the entire thickness. However, no cracks have been detected in the other slabs. It is shown that the middle slab has been embrittled by ordering to Ni4Mo due to comparative slower cooling rate. An investigation of the ordering behavior of stoichiometric Ni4Mo alloy has shown that ordering occurs homogeneously during the earlier stages of thermal aging at elevated temperatures which results in nanosized structure of ordered Ni4Mo domains capable of deforming by twinning and characterized by high strength and high ductility However, due to self-induced recrystallization by grain boundary migration during extended thermal exposure, the homogeneous nanosized structure is replaced by coarse platelets in the matrix and coarse lamellar structure at grain boundaries resulting in severe embrittlement. It is demonstrated that this problem can be combated by doping with either boron or yttrium which tend to segregate at grain boundaries and reduce their tendency toward migration and therefore self-induced recrystallization. Therefore, the desirable nanosized morphology of Ni4Mo is restored in the matrix phase and the lamellar grain boundary morphology is replaced by nanosized layers of Ni-Mo solid-solutions with compositions not susceptible to Ni4Mo ordering. As a result, the doped alloys become able to maintain high strength and high ductility after extended thermal aging at elevated temperatures.

Application of cobalt ferrite nano-catalysts for methanol synthesis by CO2 hydrogenation: Deciphering the role of metals cations distribution

Wet chemical method was employed for the synthesis of cobalt ferrite nano-catalysts. To investigate the effect of calcination temperature, the synthesized nano-catalysts were annealed at different temperature. Different analytical techniques were employed to investigate the physicochemical profiles of synthesized cobalt ferrite nano-catalysts. X-ray diffraction studies revealed the crystalline nature of the nano-catalysts. Nitrogen adsorption desorption technique showed that BET surface area was adversely affected by the increasing annealing temperature. Field emission scanning electron spectroscopy (FESEM) revealed nano-sized morphology of the synthesized cobalt ferrite nano-catalysts. Both XRD and XPS studies revealed the distribution of Co and Fe cations with respect to the applied calcinations temperature. Slurry batch reactor was used for the activity studies of the cobalt ferrite nano-catalysts towards CO2 hydrogenation to methanol. The activity studies revealed 750 °C as best calcination temperature for the cobalt ferrite nano-catalysts. Structure activity studies exhibited the correlation between the methanol synthesis rate and the distribution of cations at octahedral sites. Comparative investigations of the current studied catalysts revealed efficient methanol synthesis rate for the title reaction with the literature.

Engineering silk sericin decorated zeolitic imidazolate framework-8 nanoplatform to enhance chemotherapy

The low therapeutic effect and strong side-effect are the major barriers for clinical chemotherapy. Herein, a pH-responsive nanoplatform based-silk sericin-zeolitic imidazolate framework-8 was designed for the delivery of chemotherapeutic doxorubicin (denoted as ZIF-8@DOX@SS, ZDS), which can overcome the limitation of poor circulation stability and unexpected drug leakage in blood circulation, producing a satisfactory chemotherapy. Concretely, ZIF-8 structure shows better stability and biocompatibility owing to the protection of a nature and non-toxic sericin protein. When it comes to low pH environment (e.g. in tumor cell microenvironment), the coordination effect in ZIF-8 will be broken and release DOX drugs. The nano-sized morphology endow ZDS an efficient drug uptake and significant tumor permeability efficiency. Furthermore, the tumor-specific biodegradability makes ZDS possible to realize targeted and enhanced chemotherapy. Considering all the advantages in the study, this silk sericin-based nanosystem represent a promising strategy for the design of stimuli-responsive by using natural polymer to improve the treatment effect of chemotherapy.

Flower-like δ-MnO2 as cathode material of Li-ion batteries of high charge-discharge rates

Cathodes of lithium-ion batteries (LIBs) present stability and performance issues, therefore, the search of new cathodes is still a major concern. Manganese dioxide in delta phase (δ-MnO2) seems to be a suitable candidate since is low-cost, non-toxic and possesses a theoretical capacity of 308 mAhg−1 for one-electron transfer. In this work, we prepared δ-MnO2 by a hydrothermal method at two different reaction times. At 2 h, a flower-like nanostructure was obtained, while for a 3 h reaction time, a solid nanostructure was achieved. Both materials were tested as cathode in a LIB, finding that at slow charge-discharge rates (20 mAg−1), a material with homogeneous nanosized morphology is enough in order to obtain good capacities. But, at higher rates, our flower-like structure provides a better discharge capacity.

Nanosized Phase-Changeable "Sonocyte" for Promoting Ultrasound Assessment.

Despite the ability of microbubble contrast agents to improve ultrasound diagnostic performance, their application potential is limited due to low stability, fast clearance, and poor tissue permeation. This study presents a promising nanosized phase-changeable erythrocyte (Sonocyte), composed of liposomal dodecafluoropentane coated with multilayered red blood cell membranes (RBCm), for improving ultrasound assessments. Sonocyte is the first RBCm-functionalized ultrasound contrast agent with uniform nanosized morphology, and exhibits good stability, systemic circulation, target-tissue accumulation, and even ultrasound-responsive phase transition, thereby satisfying the inherent requirement of ultrasound imaging. It is identified that Sonocyte displays similar sensitivity as microbubble SonoVue, a clinical ultrasound contrast agent, for effectively detecting normal parenchyma and hepatic necrosis. Importantly, compared with SonoVue lacking of ability to detect tumors, Sonocyte can identify tumors with high sensitivity and specificity due to superior tumor accumulation and penetration. Therefore, Sonocyte exhibits superior capabilities over SonoVue, endowing with a great clinical application potential.

Cyanine-Assisted Exfoliation of Covalent Organic Frameworks in Nanocomposites for Highly Efficient Chemo-Photothermal Tumor Therapy.

Covalent organic frameworks (COFs) have received considerable interest because of their advanced applications. However, their low dispersibility and aqueous stability are intractable issues limiting their biomedical application. To address the issue, water-dispersible nanocomposites (COF@IR783) produced through the assembly of cyanines and COFs are proposed and prepared. Therefore, a strategy of "killing three birds with one stone" is developed. First, the nanocomposites exhibit superior dispersibility and aqueous stability compared to COFs. The nanocomposites have a nanosized morphology and negative charges, which are in favor of improving the blood circulation and enhanced permeability and retention-mediated tumor-targeting delivery therapy for in vivo application. Second, the nanocomposites have enhanced photothermal therapy (PTT) ability in the near-infrared region compared to cyanines. The nanocomposites also have a photoacoustic imaging ability, which can guide the antitumor therapy in vivo. Lastly, the nanocomposites can be further used as drug-delivery carriers for loading the anticancer cis-aconityl-doxorubicin (CAD) prodrug. In comparison with individual PTT or chemotherapy, the combination of PTT and chemotherapy achieved with COF@IR783@CAD synergistically induced the death of cancer cells in vitro, and an intravenous injection of COF@IR783@CAD in mice resulted in significant tumor ablation. This work indicates that the dispersibility and aqueous stability of COFs can be appropriately overcome through a rational design and can further expand the biomedical applications of COFs.

Examining relationships between properties of weathered asphalt mixtures and nano-sized morphology of their recovered binders

The objective of this study was to examine the relationship between the properties of weathered asphalt mixtures and the nano-scaled morphology of their recovered asphalt binders. Firstly, asphalt mixtures of open-graded friction course (OGFC) were weathered in an accelerated weathering machine (AWM) and then tested for selected properties. Secondly, the asphalt binders were recovered using an Abson method and investigated for their nano-scaled morphology by an atomic force microscopy (AFM). Finally, the relationships between the selected properties of the weathered mixtures and the nano-scaled morphology of their asphalt binders were established. The results revealed that (1) the increasing height roughness and wrinkle degree of the nano-morphology of the recovered asphalt binder could be well exhibited by the increasing AFM indexes: image surface area difference (ISAD), height root-mean-square (R q) and the difference between maximum and minimum height (R max), a clear demonstration of how asphalt binder surfaces stiffen with age; (2) the cracking-resistance at low temperature, the rutting resistance and the splitting strength of the weathered OGFC mixtures decreased, while the AFM indexes of the nano-sized morphology increased as the weathering time increased; (3) There was a linear relationship between the properties of the weathered mixtures and the three AFM indexes.

Effect of Nickel Ferrite Addition on Characteristics of Nanostructured Nickel Ferrite/Hydroxyapatite Ceramic

Abstract A composite ceramic of hydroxyapatite (HAp) and nickel ferrite (NiFe2O4) has application potential in bone tissue regeneration and heavy metal adsorption. In this present work, the nanostructured NiFe2O4/HAp ceramic was successfully fabricated through a simple preparation technique using chicken eggshells as a calcium source. Characteristics of the composites were investigated for various NiFe2O4/HAp weight ratios from 2-10 wt%. The XRD results indicated no other impurity phase formations, illustrating the stability of the occurred HAp and NiFe2O4 phases. Phase fractions of NiFe2O4 were found to increase from 12.12 to 22.38 wt% with increasing NiFe2O4. FT-IR results revealed the interaction of HAp and NiFe2O4 structures in composite ceramics, further supported with varying of the lattice parameter and the crystallite size. Magnetization of composite was shown to increase from 0.26 to 2.08 emu/g with increasing NiFe2O4. SEM and BET results revealed nanosized morphology with the enhancement of porosity and interconnectivity when increasing NiFe2O4.

Synthesis and characterization of SrTiO3 and g-C3N4-SrTiO3 nanocomposite by screw capped method

Synthesis and characterization of SrTiO3 nano particles with varying proportions of Sr and Ti precursors were investigated. In the present protocol, the screw cap vessel is employed to produce distinct nanosized morphology of cubic perovskite-type SrTiO3. Additionally, a hybrid nanocomposite was fabricated by grinding the SrTiO3 and g-C3N4 samples. As-synthesized samples were examined by using UV-DRS, FT-IR, XRD, TEM, and SEM to confirm the structure and morphology. Morphology of nanoparticles (10–30 nm), porous nanoparticles (10–40 nm) porous size (3–8 nm), and amorphous particles (25–100 nm) were observed. By the addition of the g-C3N4, to SrTiO3 a shift in band gap energy is observed, which encouraged us to study further. The sheet-like graphene structure facilitated to get stable SrTiO3 which can be utilized in photovoltaics.

Production of nanostructured \u03b3-alumina from aluminum foundry tailing for catalytic applications

Aluminum production industry tailings are considered as hazardous solid wastes accompanied by a variety of serious disposal, environmental, and public health issues. This study is devoted to presenting a promising solution for dealing with such problems. Within the scope of the present study, synthesis of nanostructured γ-alumina from aluminum foundry tailing using a novel process was presented. The proposed process will provide a multilateral advantage to both environment and industries. Firstly, the amount of tailing and accordingly, disposal cost could be partly lessened; secondly, the environmental pollution can be reduced, and finally, if possible, green production of advanced materials from this kind of waste at a rational expense can bring about the conservation of natural sources and also gain economic benefits. Characterization of the as-synthesized products was performed using X-ray diffractometry (XRD), X-ray fluorescence (XRF), Fourier-transform infrared (FTIR) spectroscopy, field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDAX), and dynamic light scattering (DLS) for crystalline phase analysis, chemical composition, chemical bond recognition, morphology, elemental analysis, and particle size distribution, respectively. The chemical composition analyzed by XRF indicated that the as-synthesized alumina exhibits a purity of more than 97 wt%. The XRD pattern majorly possessed characteristic peaks related to the gamma phase of alumina. Microstructural analyses by FESEM and TEM confirmed the nano-sized morphology of the as-synthesized γ-alumina.