Ball Milling Method Research Articles

Lattice energy transfer from homo-crystalline substitution for enhanced piezo-photocatalytic CO2 conversion

The rapid recombination of carriers and large activation energy of CO2 compromise the efficiency of CO2 photoreduction. Herein, SrTiO3 (STO) with different molar ratios of La3+ and Al3+ double-site homo-crystalline substitution is prepared by a ball-milling molten salt method. The concentration of Ti3+ and excess oxygen vacancies decrease to improve the catalytic activity. Meanwhile, the double sites act as electron transfer platforms for easy electron transfer from the bulk phase to the surface to foster CO2 photoreduction. Not only that, the energy transfer due to doping-induced lattice distortion can potentially enhance the photocatalytic activity. A piezoelectrically polarized electric field is introduced to further expedite charge transport. As a result, the activity of La, Al-STO piezo-photocatalytic CO2 reduction is improved to 39.17 µmol g-1h−1, which is more than seven times better than that of the pure STO. Furthermore, CO2 adsorbs spontaneously on the catalysts because the thermodynamic energy barrier decreases due to the piezoelectric force, which is verified by density-functional theory calculation. This study reveals the great potential of double-site homo-crystalline substitution of STO pertaining to the charge transport kinetics and thermodynamics of the catalytic reaction in the piezo-photocatalytic CO2 process.

Enhanced ethanol synthesis via CO2 hydrogenation using La-Doped CuFeOx catalysts

CO2 hydrogenation is an effective solution for direct ethanol production as it realizes a high-value utilization of waste CO2. As it requires a synergistic multi-step process of CO2 activation, asymmetric hydrogenation of CO, and precise coupling of C-C bonds, the design of highly active and selective catalysts for such procedures remains challenging. In this study, we prepared a series of La-doped CuFe catalysts using a simple and green solvent-free ball milling method to accelerate the rate of CO2 hydrogenation to ethanol generation. HRTEM, in situ XRD, EPR, and CO2-TPD analyses indicated that the doping of moderate amounts of La can significantly improve the dispersion of the Cu and Fe species, enhance the interaction between the CuFe species, decrease the reduction temperatures of CuO and Fe2O3, promote the formation of oxygen vacancies during the reaction process, and enhance CO2 adsorption and activation ability. DFT calculations, XPS, in situ FTIR, and CO-TPSR-MS analyses indicated that the transfer of electrons from the Fe to La species decreased their electron cloud densities, weakened the bridge type adsorption of CO, enhanced the linear adsorption of CO, and optimized the ratio of the dissociative and non-dissociative adsorption of CO intermediates, which ultimately resulted in a better matching of the rates of generation of CHx* and C(H)O* intermediates. The occurrence of C-C coupling at the abundant Cu0-Fe5C2 interface promoted the highly efficient synthesis of ethanol, achieving yields as high as 13.5 % over the 5La-CuFeOx catalyst, ranking the top level among the reported catalysts in the literature. This study presents a feasible strategy for the targeted regulation of multicomponent active centers.

Preparation of phosphorous ionic liquids and its effect on the properties of ABS

AbstractTo improve the thermal conductivity and mechanical properties of graphene‐acrylonitrile butadiene‐styrene plastic (ABS) composite, sub‐phosphite‐based ionic liquid (IL) was synthesized, and its structure was characterized by FTIR, NMR, and mass spectrometry. IL was as a modifier, and graphite powder (G powder) was modified by the ball milling method to obtain functional graphene thermal conductive filler (G‐IL). The structure and morphology of G‐IL were characterized by FTIR, X‐ray photoelectron spectroscopy (XPS), XRD, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results of the Molau test showed that the presence of IL improved the interfacial interaction of G‐IL and ABS, enhanced the dispersion of G‐IL in the ABS matrix, made G‐IL contact with each other, and it was easier to establish a thermal conduction network and promote phonon transfer. The thermal conductivity of 9 wt% G‐IL/ABS composite was 0.392 W·m−1·k−1, which was 96% and 14% higher than that of pure ABS and G/ABS composite, respectively. The tensile strength and bending modulus of 9 wt% G‐IL/ABS composite were 44.89 and 2124.37 MPa, which were 13% and 11% higher than those of pure ABS, respectively. The impact strength of 9 wt% G‐IL/ABS composite was 34.17 kJ/m2. It was 18% and 7% higher than that of pure ABS and 9 wt% G‐IL/ABS, respectively.Highlights Phosphorus imidazole ionic liquids were prepared. Graphene was modified by ionic liquids through non‐covalent. Enhanced mechanical properties and thermal conductivity of G‐IL/ABS composites.

The Effect of CeO2 on the Catalytic Activity and SO2 Resistance of the V2O5-MoO3/TiO2 Catalyst Prepared Using the Ball Milling Method for the NH3-SCR of NO

The Effect of CeO2 on the Catalytic Activity and SO2 Resistance of the V2O5-MoO3/TiO2 Catalyst Prepared Using the Ball Milling Method for the NH3-SCR of NO

Synergistic Suppression of Bipolar Effect and Lattice Thermal Conductivity Leading to High Average Figure of Merit in Bi0.4Sb1.6Te3 Materials through Alloying with AgSbTe2.

Bismuth telluride-based materials have been widely used in commercial thermoelectric applications due to their excellent thermoelectric performance in the near-room-temperature range, yet further improvement of their thermoelectric properties is still necessary. Moreover, the narrow band gap of these materials results in a bipolar effect at elevated temperatures, which causes severe degradation of the thermoelectric performance. In this work, the commercial Bi0.4Sb1.6Te3 was alloyed with AgSbTe2 by using high-energy ball milling method combined with spark plasma sintering. It was found that ball milling can effectively reduce the lattice thermal conductivity of the samples. The alloying of AgSbTe2 leads to a gradual increase in hole carrier concentration, resulting in an enhanced electrical conductivity and optimized power factor. Additionally, the bipolar effect is also weakened due to the increased hole carrier concentration. Furthermore, the substitution of Ag in the Bi/Sb sublattice causes further reduction in the lattice thermal conductivity. Ultimately, the sample alloyed with 0.15 wt % AgSbTe2 demonstrates its best thermoelectric performance with a maximum zT of 1.35 at 393 K, showing a 20.5% improvement compared to the commercial sample. Besides, its average zT reaches a high value of 1.25 between 303 and 483 K, with a 27.6% improvement compared to that of the commercial sample.

Green massive mechanical synthesis of highly efficient Zn-Doped Cs3Cu2I5 for LED and X-ray imaging applications

As a new generation of environmentally friendly halide materials, Cs3Cu2I5 shows up the promising application in scintillation, LED, and photoelectric detection fields. However, liquid phase methods cannot produce Cs3Cu2I5 on a large scale, and the preparation process is accompanied by serious pollution. Although the ball milling method can solve the problems caused by the liquid phase synthesis method, the Cs3Cu2I5 obtained has many surface defects and low luminescence efficiency. In this work, a strategy of doping-assisted ball-milling synthesis using ZnI2 is proposed. Similar to the chemical preparation of Cs3Cu2I5, the iodine-rich environment during the modified ball milling process can also play a role in repairing surface defects. And it has been demonstrated through experiments and first principles calculations that the distortion of [Cu2I5]3- under ground/excited state can be adjusted through doping Zn into the Cu1 site, the formation barrier of self-trapped excitons is reduced, and the luminous efficiency of Cs3Cu2I5 is significantly improved. Subsequently, using the simple hot-pressing method, the representative Cs3Cu2I5:1.0Zn sample was combined with commercially available polypropylene to fabricate Cs3Cu2I5:1.0Zn@PP film. Finally, the potential applications of the newly-developed film in portable and customizable WLED and scintillation fields were explored.

Development and characterization of PLA nanocomposites reinforced with bio-ceramic particles for orthognathic implants: Enhanced mechanical and biological properties

The clinical application of osteofixation materials is crucial for maxillofacial reconstruction and orthognathic surgeries. To overcome the limitations of traditional metallic implants, bioabsorbable materials are gaining popularity due to their ability to avoid secondary removal surgeries and reduce stress shielding. This study investigates third-generation biomaterials, focusing on polylactic acid (PLA) for its biocompatibility and biodegradability, and hydroxyapatite (HAP) for its bioactive osteoconductive and bioresorbable properties. Eggshell nanoparticles (ES-NP), HAP, and bioinert alumina particles coated with titanium dioxide (TiO2@Al2O3) were prepared using ball milling, co-precipitation, and sol-gel methods, respectively. PLA-based nanocomposites PLA/ESNP/Al2O3 (PEA), PLA/HAP/Al2O3 (PHA), PLA/ESNP/TiO2@Al2O3 (PEAT), and PLA/HAP/TiO2@Al2O3 (PHAT) were fabricated via solvent casting. Characterization techniques including X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), and Field-Emission Scanning Electron Microscopy (FE-SEM) were used to analyze the developed nanoparticles and composites. Results indicated PEAT and PHAT composites exhibited tensile strengths of 33.59 ± 0.38 MPa and 32.46 ± 0.46 MPa, tensile moduli of 1756.17 ± 95.43 MPa and 2367.21 ± 158.84 MPa, and shore d hardness values of 84.10 ± 1.45 SHN and 78.00 ± 2.25 SHN, respectively. Both composites achieved a wettability angle of ∼65° and surface roughness below 2.19 μm, enhancing osteoblast adhesion. Additionally, MG63 cell viability was approximately 80 %, and hemolysis rates were below 2.17 %, demonstrating their potential for maxillofacial implant applications.

A Rapid Synthesis of Amorphous LiTaOCl4 Solid Electrolytes Through a Two‐Step Reaction Pathway for High‐Rate and Long‐Cycling Lithium Batteries

AbstractA simplified process to prepare solid electrolytes (SEs) that fulfill long cyclability, fast‐charging performance, and wide‐temperature feasibility in all‐solid‐state lithium batteries (ASSLBs) is important. Here, amorphous LiTaOCl4 (aLTOC) SE is synthesized within only four hours via a two‐step reaction by high‐energy ball milling method, which exhibits high ionic conductivity and excellent interfacial compatibility. A bilayer SE based on aLTOC and sulfide along with corresponding ASSLBs, are constructed. Furthermore, slight evolution of the unusual microstructure in the chloride/sulfur interfacial region is observed and analyzed. Density functional theory calculations show that S tends to displace O sites in TaO2Cl4 octahedra instead of Cl sites. As a result of the enhanced interfacial stability and reduced formation of ionically insulating phases, the assembled ASSLBs achieve superior rate performance and cyclability in a wide temperature range. Notably, the ASSLBs show capacity retention of 84.4% and 77.6% after 2000 and 1000 cycles at current density of 10C at 30 and 60 °C, respectively. Importantly, even under −20 °C, the cell works stably over 1600 cycles with capacity retention of 76.3% at 0.5C. The work pave the way for the massive production of high‐performance amorphous chloride electrolytes and the realization of fast‐charging ASSLBs with long cycle life.

Investigation of Microhardness, Microstructural, Tribological, and Thermal Properties of Al7075/TiO2/Kaoline Hybrid Metal Matrix Composites Produced by Powder Metallurgy Process

The shift from traditional, single‐component metals and alloys continues, and researchers are currently investigating alternative materials. This evolution has led to the creation of innovative materials, including hybrid metal‐matrix composites. The present study aims to investigate the microstructural, surface morphological, and thermal properties of a novel Al7075/TiO2/Kaoline hybrid metal‐matrix composite prepared using high‐energy ball milling and sintering methods. In this study, phases related to the composite components are formed depending on the milling time, no undesirable phase is formed, but the peak intensities decreas as the milling time increases. Particle size increases from 63 to 215 μm with increasing milling time. Increasing the kaoline reinforcement ratio and sintering temperature increases the microhardness from 62.27 ± 2 to 75.83 ± 2 HV, and reduces the friction coefficient from 0.82 ± 0.01 to 0.62 ± 0.01. The wear rate of the composite without kaoline addition is 2.1 (mm3 m−1) × 10−3, while with 6 wt% kaoline addition, it decreases to 1.5 (mm3 m−1) × 10−3. There are no cracks in the composite other than plastic deformation due to sintering and wear. Peaks indicating endothermic and exothermic reactions during continuous heating occurr in the 635–750 °C temperature range.

Enhancements in Hydrogen Storage Properties of Magnesium Hydride Supported by Carbon Fiber: Effect of C–H Interactions

Carbon-based materials with excellent catalytic activity provide new ideas for the development of magnesium-based hydrogen storage. C-H bonding interactions may play a key role in performance improvement. In this work, we comprehensively compare the magnesium-carbon cloth composites (CC) prepared by method of dry ball milling and wet impregnation. The results were that the hydrogen release activation energy (Ea) of MgH2@CC composites prepared by wet immersion method was 175.1 ± 19.5 kJ·mol−1, which was lower than that of pure MgH2 (Ea = 213.9 ± 6.4 kJ·mol−1), and the activation energy of MgH2-CC composites prepared by ball milling method was 137.3 ± 8.7 kJ·mol−1, which provided better results. The kinetic enhancement should be attributed to C-H interactions. The presence of carbon carriers and electron transfer to reduce the activation energy of Mg-H bond fracture. These results will provide further insights into the promotion of hydrogen ab-/desorption from metal hydrides.

General Synthesis of High-Entropy Oxides and Carbon-Supported High-Entropy Oxides by Mechanochemistry.

High-entropy oxides (HEOs) have been receiving a lot of attention due to their excellent properties. However, current common methods for preparing HEOs usually involve high-temperature processes. The development of green synthesis techniques remains an important issue. Carbon-supported HEOs have shown excellent performance in electrochemical energy storage in recent years. Crucially, the traditional methods cannot synthesize carbon-supported HEOs under N2 or air atmospheres. Toward this end, a universal method for preparing carbon-supported HEOs was proposed. During this process, without high-temperature post-treatment, high-entropy LaMnO3 could be synthesized in 2 hours using the mechanical ball-milling method. Furthermore, this method was universal and has been proved in the synthesis of a series of HEOs such as PrVO3, SmVO3, and MgAl2O4. The LaMnO3 species synthesized by this method exhibit excellent catalytic performance in CO combustion and could maintain a conversion rate of over 97 % for 350 hours. Subsequently, carbon-supported HEOs could be obtained with 0.5 hours of additional ball-milling, offering significant advantages over traditional methods. This process provides a potential method to synthesize carbon-supported HEOs.

Effective periodate activation by the ball-milled bimetallic zero-valent iron/manganese oxides catalyst for sulfamethoxazole degradation

Developing a green and efficient catalyst for oxidant activation to tackle refractory organics pollution is challenging for water purification. In this study, we prepared a zero-valent iron-based bimetallic catalyst (ZVI/Mn3O4) for periodate (PI) activation using a simple and convenient ball-milling method. Electrochemical characterization and theoretical calculations confirm that the synergy between Fe and Mn enables the ZVI/Mn3O4 system to exhibit higher electron transfer efficiency compared to its individual components. Consequently, the ZVI/Mn3O4/PI system demonstrated enhanced PI activation and significantly improved removal of sulfamethoxazole (SMX), with reaction rates being 18.61 to 57.01 times higher than the comparison systems. The influence of various physicochemical parameters on SMX removal was investigated, confirming the wide tolerance ZVI/Mn3O4/PI system towards multiple aqueous matrices. Furthermore, the scalability of this system for industrial applications was validated through the preparation of larger batches of catalysts (4.21 g per batch) and testing in a custom-designed magnetic plate continuous-flow reactor. Quenching experiments and electron spin resonance tests confirmed that •O2– and 1O2 were the primary reactive species responsible for SMX degradation, with no toxic iodine byproducts detected, attributed to the carefully designed catalyst, which optimized the interaction between PI and the catalyst. Based on these findings, a potential catalytic mechanism and degradation pathway were proposed, highlighting ZVI's role as an electron pump to enhance Mn3O4's activation of PI. Additionally, toxicity assessments via prediction, zebrafish cultivation, wheat germination, and E. coli culture confirmed the excellent detoxification capability of ZVI/Mn3O4/PI system for SMX degradation. Overall, this work provides a new research paradigm for the convenient manufacture of ZVI-based catalysts and the development of advanced techniques for PI activation in water purification.

Exfoliation of boron nitride nanosheets by liquid phase method based on deep eutectic solvents and their thermal management application

AbstractBoron nitride had emerged as an innovative thermally conductive filler, garnering increasing attention from researchers. However, there was a need to create new methods for efficiently producing functionalized boron nitride nanosheets with enhanced thermal conductivity and dispersion. In this study, a novel approach was introduced to utilize deep eutectic solvents as additives to facilitate the exfoliation of boron nitride nanosheets. This method offered significant advantages in terms of cost‐effectiveness (low additives level) and high yield (about 60%). Furthermore, the resulting epoxy resin composite material exhibited outstanding thermal conductivity and thermal management properties. The thermal conductivity of EP/d‐BNNS composites reached 1.02 W/mK at 20 wt% d‐BNNS loading. Additionally, the composite material demonstrated good thermal stability and low dielectric properties. This work demonstrated that this proposed approach represents an effective means for the scalable production of boron nitride nanosheets.Highlights The boron nitride nanosheets were obtained by deep eutectic solvents (DES) ball milling method. The exfoliated boron nitride exhibits superior dispersion stability. The thermal conductivity of EP composites is significantly improved.

Manganese nanoparticles catalyzed the formation of mesoporous helical nitrogen-doped carbon nanotubes enabled aldosterone biosensing

Primary aldosteronism (PA) is the foremost form of secondary hypertension that affects 5–20 % of healthy humans via the excessive secretion of aldosterone (ALD), which increases the level of potassium excretion and thus produces various critical combined diseases. Thus, determining trace-level ALD content in human blood or urine samples is a crucial factor in diagnosing a life-threatening disease called PA. Herein, nanosized manganese particles encapsulated within the tunable helical-shaped N-doped mesoporous carbon nanotubes (Mnx@H-NCNTs) are synthesized by a simple and facile ball-milling method at different reaction times (1, 6, 12, and 18 h). The influence of ball-milling process time on the final morphology of the as-synthesized Mnx@H-NCNTs nanostructures is systematically investigated. In order to fabricate an ALD biosensor electrode, the immobilization of Anti-ALD antibodies (Anti-ALD) on the surface of the Mn@H-NCNTs-12H electrode (Anti-ALD/Mn@H-NCNTs-12H) is achieved via the interactions of combined interactions of hydrogen bonds, Van der Waals’ force, negatively charged carboxylic acid functionalities of antibodies and positively charged metal centers, and π-π stacking interaction between nucleosides of Anti-ALD and mesoporous H-NCNTs. In addition, BSA was used as a blocking additive for covering non-specific adsorption sites of Anti-ALD/Mnx@H-NCNTs (BSA/Anti-ALD/Mn@H-NCNTs-12H) nanostructured electrodes. The BSA/Anti-ALD/Mn@H-NCNTs-12H can be used as an effective signal amplifying probe for ALD detection through a noticeable reduction in the amperometric i-t current response over a linear range from 1 to 2500 pM, with a LOD of 0.72 pM (S/N = 3). The practical applicability of BSA/Anti-ALD/Mn@H-NCNTs-12H is further demonstrated by the detection of ALD from 1 to 20 nM in human blood or urine samples with a recovery ranging from 90.5 to 97.0 %, indicating its potential use in clinical analysis.

Interface-driven microwave absorption enhancement in Mn-optimized Co2FeAl1-xMnx Heusler alloys

To address the urgent need for efficient and stable electromagnetic wave absorbing materials for electromagnetic interference (EMI) protection, we synthesized Co2FeAl1−xMnx Heusler soft magnetic alloys using a high-energy planetary ball milling method. We comprehensively analyzed their structural characteristics, surface morphology, magnetic properties, and electromagnetic parameters to explore their potential in electromagnetic wave absorption. The results show that incorporating manganese (Mn) significantly changes the alloys' crystal structure, surface morphology, and magnetic properties, greatly enhancing their wave absorption performance. The Mn doping specifically alters the surface morphology, which plays a crucial role in influencing the wave absorption characteristics of the Heusler alloys. When the Mn content increased to 25 %, the sample exhibits superior wave absorption, achieving the maximum reflection loss of −44.83 dB at 13.68 GHz with a thickness of 1.5 mm and an effective absorption bandwidth of 5.52 GHz. With a significant increase in the aspect ratio and noticeable changes in surface morphology, the sample with 75 % Mn content shows exceptional performance with an effective absorption bandwidth of 5.68 GHz, representing the highest effective absorption bandwidth in single-phase Heusler alloys. The Mn doping strategy effectively improves the material's impedance matching by adjusting its permittivity and permeability, facilitating multiple polarization relaxation mechanisms and significantly enhancing the alloys' electromagnetic wave absorption efficiency. Our study provides detailed experimental data for optimizing the electromagnetic wave absorption characteristics of Heusler alloys, verifies their practical application potential, and paves the way for developing new high-performance electromagnetic wave absorbing materials.

A composite anode based on intercalation and conversion mechanism for high-rate lithium-ion batteries

To increase the specific capacity and cycle stability of lithium-ion batteries at high current density, we have investigated the anode materials. Among them, black phosphorus has attracted attention because of its large theoretical specific capacity (2596 mA h/g). However, the moderate conductivity of black phosphorus itself makes it less effective. The addition of graphite to form P-C and P-O-C bonds with black phosphorus enhances the performance of the battery cell. Lithium ions are primarily stored in black phosphorus-graphite layered structural materials via an intercalation mechanism, which improves electrochemical performance at tiny current density but is inadequate for charge/discharge cycling at high current density. In addition, lithium ions also can undergo conversion mechanism with metal oxide materials (e.g. Tungsten trioxide). While this conversion mechanism enables more stable battery cycling at high current density, the specific capacity remains insufficiently high. Higher charge/discharge specific capacity and long cycle stability of lithium-ion batteries at high current density can be realized by the joint action of the two mechanisms. In this work, black phosphorus, graphite, and tungsten trioxide (BP/G/WO3) composites are prepared by ball milling method. A comprehensive series of electrochemical analyses reveals that the BP/G/WO3-532 electrode (BP, graphite, and WO3 mass ratio of 5:3:2) exhibits the most substantial enhancement in the cycling stability of lithium-ion batteries. The anode exhibits a high specific capacity of 1463.1 mA h/g at 6 A/g and presents a retention capacity of 1159.8 mA h/g after 300 charge/discharge cycles, indicating a high cycle stability and fast reaction kinetics. This result is mainly attributed to the joint action of two mechanisms of composites.

Reinforcement of recycled polypropylene by nano lanthana with improved thermal, mechanical and antimicrobial properties

Abstract In this study, lanthanum oxide (La2O3) nanoparticles or lanthana were synthesized by the planetary ball milling method and then used as a filler for the preparation of the polypropylene (PP) based nanocomposites by solution mixing method. The PP used in the study was derived from the discarded saline bottles. The structural and the surface morphology of the synthesized lanthanum oxide nanoparticles were characterized by XRD, SEM and FTIR. The thermogravimetric analysis (TGA) study revealed that the thermal stability of the nano lanthana composites increased with the addition of the lanthanum oxide nanoparticles. The mechanical properties, such as Young’s modulus and tensile strength, were also improved by the addition of the lanthanum oxide nanoparticles to the PP matrix. The composites also showed antibacterial activity against Escherichia coli bacteria. This approach not only mitigates medical plastic waste and environmental impact but also paves the way for versatile polymer nanocomposites with extensive industrial applications, especially in biomedical packaging.

Effect of SiC doping on microwave absorbing properties of ball-milled carbonyl iron/MoS2 composites

Using MoS2 to prepare novel composite absorbing coatings is an effective strategy to enhance electromagnetic wave absorption. In order to explore the preparation process of large-scale preparation of MoS2 composite absorbing materials, a Fe/MoS2/SiC laminated composite absorbing material was prepared by high-energy ball milling method to realize the absorption of electromagnetic waves. By adjusting the proportion of SiC, SiC, MoS2 and Fe were ball-milled at room temperature for 20 h, and the dielectric properties were improved to achieve good absorbing effect. The microstructure and properties of the materials were measured by XRD, SEM, Raman, XPS, HRTEM, VSM and VNA. The results show that the doping of appropriate amount of SiC reduces the interplanar spacing of MoS2 and increases the edge points, which increases the conductivity of MoS2. MoS2 reduces the number of layers and increases its size and area, which improves the dielectric properties of Fe/MoS2 and optimizes the electromagnetic parameters of the composites. When the ratio (mole) of SiC, Fe and MoS2 is 3:6:2, the best electromagnetic wave absorption effect is obtained, the lowest electromagnetic wave reflection loss is −72.98 dB, and the best bandwidth is 3.04 GHz when the matching thickness is 6.53 mm.

Fabrication of Ag Nanoparticle-Embedded Covalent Organic Frameworks for Oil Gel with Long-Term Stability and High Lubrication Performance.

In previous reports, covalent organic frameworks (COFs) have demonstrated significant potential as lubricant additives. Herein, we embedded Ag nanoparticles in the DT-COF (polycondensation polymer of 2,5-dihydroxyterephthalaldehyde and 4,4',4″-(1,3,5-triazine-2,4,6-triyl) trianiline) matrix via the ball milling method and utilized this composite (Ag@DT-COF) as an additive for supermolecule oil gel. The low molecular weight gelator effectively mitigates the dispersion challenges of COFs in lubricant oil, while the embedded Ag nanoparticles enhance the repairing effect and antipressure performance of the lubricant. The resulting Ag@DT-COF gel exhibits a reduction in the average friction coefficient and wear volume of base oil by 46.0% and 87.5%, respectively, and increases the load-carrying capacity to 750 N. The remarkable tribological properties are attributed to the easy adsorption of DT-COF, antiwear characteristic of Ag nanoparticles, and the gelator that ensures the long-term stability of oil gel.

Nano-reusable CuO-ZnO Catalyzed One-Pot Synthesis of 1-Amidoalkyl-2-Naphthols under Green Condition

Introduction: The Developed CuO-ZnO nanocomposite has been demonstrated as a new and environmentally friendly catalyst for one-pot multicomponent reaction between aldehydes, 2- naphthol and amides in the synthesis of 1-amidoalkyl-2-naphthols. Method: The new catalyst was synthesized by a ball-milling method by mixing a mixture of CuO and ZnO powder in various proportions and characterized by different spectroscopic methods such as powder X-ray diffraction (pXRD), Scanning Electron Microscopy (SEM), UV-Visible analysis, EDAX elemental analysis and mapping. The advantages of the devised protocol include a green approach, simple work-up procedures, avoidance of hazardous solvents, and good to excellent yields. RE Sult: Evaluation of the catalyst performance in the synthesis of some 1-amidoalkyl-2-naphthols showed presentable results. Sixteen derivatives were synthesized in desirable yield by our new method (4a-4p). CuO-ZnO nanocomposite as a safe and efficient catalyst could be reused up to 5 runs for the synthesis of naphthol derivatives without any significant decrease in its potency. Conclusion: The High purity of the products and desirable yields are other points that make the present work more attractive.