Mechanical Ball Research Articles

Oxychloride Polyanion Clustered Solid-State Electrolytes via Hydrate-Assisted Synthesis for All-Solid-State Batteries.

Solid-state electrolytes (SSEs) play a vital role in the development of high-energy all-solid-state batteries. However, most adopted mechanical ball milling and/or high-temperature annealing are ineffective approaches for large-scale synthesis. Herein, a universal and scalable hydrate-assisted strategy for the synthesis of oxychloride SSEs is developed based on the chemical reaction among alkali chlorides, AlCl3, and AlCl3·6H2O. The synthesized aluminum-based oxychloride SSEs possess a high Li+ conductivity over 1mScm-1 at 30°C. The final aluminum-based oxychloride SSEs are structurally heterogeneous with nm-sized LiCl-like and LiAlCl4 crystallites and large amounts of amorphous [AlaObClc](2 b + c -3 a )- components. Faster local mobility of Li+ ions in amorphous structures is verified and is attributable to weakened Li+-X- interactions ensured by the [AlaObClc](2 b + c -3 a )- polyanions. The potential applications for this synthesis technique are further demonstrated by kilogram-scale reactions and synthesis of other oxychloride SSEs including zirconium-based and tantalum-based analogs. These findings not only provide a new simple, scalable, and energy-efficient synthesis route for oxychloride SSEs but also further promote their application in all-solid-state batteries.

Study on the hard carbon anode from different precursors for sodium ion batteries

Sodium-ion batteries (SIBs) are commonly utilized in power storage applications. It can be used as alternatives to lithium-ion batteries. Nevertheless, the development of SIBs is restricted by anode materials due to the high redox potential and large irreversible capacity. As a common anode material of SIBs, hard carbon exhibits a substantial interlayer spacing and a excellent reversible specific capacity, while the properties and costs are affected by its precursors. This article mainly describes the sodium storage principle of hard carbon and compares the performances as well as modification methods of hard carbon produced from various precursors. The hard carbon basing on coal has the advantages of low cost due to the abundant reserves of coal precursors and low redox potential. Biomass-based hard carbon has natural pores which can assist the sodium ions transport in carbon materials. We further explain the effects of modification strategies such as heteroatom doping, activation treatment and mechanical ball milling on electrochemical properties of hard carbon. Finally, this paper recognizes the existing problems and corresponding solutions of materials made of hard carbon and looks forward to the future research focus on hard carbon materials.

Progress of silicon and graphene composites in lithium-ion battery anodes

As society progresses, the need for high-power, long-life energy supply devices gradually increases. Lithium-ion batteries (LIBs) with large energy reserves and high power have recently become the preferred choice. The anode of LIBs plays a crucial role in battery performance, safety, and cycle life. Typically, graphite materials are used for LIBs anodes. Still, they have drawbacks such as low first-time Coulombic efficiency, capacity degradation, safety issues, short cycle life, insufficient gram capacity, and purity and side reactions, which limit the application of LIBs. Therefore, new harmful electrode materials are in demand. Graphene and silicon are both environmentally friendly and sustainable materials. They both have the advantages of high theoretical capacity and high energy density, which are critical materials for developing LIBs. Combining the two can exert a synergistic effect and jointly improve the cycle stability of the battery. In this paper, we review the preparation methods of graphene and silicon composites in recent years, including mechanical ball milling and hydrothermal and thermal reduction methods. In addition, graphene and silicon composites have been explored for LIBs applications.

Iron-Based Materials Synthesized by Mechanical Ball Milling for Environmental Contaminants Removal: Progress and Prospects

Iron-Based Materials Synthesized by Mechanical Ball Milling for Environmental Contaminants Removal: Progress and Prospects

Mechanochemical Synthesis of Carbazole Isomer Phosphors.

The 1H-benzo[f]indole (Bd[f]), a carbazole (Cz) isomer is first reported as the source of Cz-based phosphors in 2020. In this work, the novel carbazole isomers, 1H-benzo[g]indole (Bd[g]) based derivatives, are synthesized by a one-step solvent-free mechanical ball milling reaction, establishing a facile, efficient, and environmentally friendly method for the synthesis of new Cz isomer phosphorescent derivatives with high yields compared to previously reported multi-step solvent-based thermochemical synthesis routes of Bd[f] derivatives with low yields. Six Bd[g] derivatives with different substituents, namely OCH3-Bd, In-Bd, Bn-Bd, F-Bd, Cl-Bd, and Br-Bd, are synthesized, which exhibit distinctly different single-crystal structures and phosphorescent properties. After irradiation with 365nm UV light, Bd[g] derivatives-doped poly (methyl methacrylate) (PMMA) films exhibit photoactivated green room-temperature phosphorescence with ultra-long lifetimes up to 1.65s. Interestingly, the phosphorescence is stable in seawater along with good bactericidal properties, which also provide new candidates for indole-based marine antifoulants. This study demonstrates that mechanical ball milling is an efficient method for the synthesis of benzoindole heterocycles. Bd[g], as new members of the benzoindole family, are new building units to construct carbazole isomer phosphorescent molecules besides Bd[f].

Effect of Al and Zn on Oxygen Evolution Reaction of (FeCoNiMnCu)3O3.2

AbstractBecause of its low cost and abundant sources, hydrogen serves as a clean energy alternative capable of successfully substituting fossil fuels. A highly efficient method for generating hydrogen energy currently is by the electrolysis of water. The oxygen‐extraction reaction (OER), a component of water electrolysis, requires a complex chemical pathway that involves multiproton and multielectron interactions. To enhance reaction efficiency in the OER process, catalysts are crucial; thus, the search for high‐performance, cost‐effective catalysts is underway. This experimental study involved the enhancement of the five‐membered high‐entropy oxide (FeCoNiMnCu)3O3.2 by incorporating a sixth group element (Zn, Al). The organization, morphology, and OER properties were analyzed following the preparation utilizing a mechanical ball milling process. A series of rock salt‐type hexagonal high entropy oxides with differing ball milling durations were synthesized to investigate the influence of the production method on the surface shape and catalytic properties of high entropy oxides. The results indicated that the single‐phase rock salt structure of (FeCoNiMnCuAl)3O3.5, a high‐entropy oxide, exhibited significantly altered diffraction peaks, hence improving OER performance. Optimization of the preparation technique revealed that a 72‐h ball milling duration resulted in an overpotential of merely 293 mV and an electrochemically active surface area approximately double that of the other milling durations.

Hydroconversion of waste polyethylene plastics under mild conditions using mechanically mixed bifunctional catalysts: Impact of metal-acid balance and proximity

The disposal of non-biodegradable waste polyolefin plastics poses a serious environmental threat, highlighting the need for cleaner and more efficient thermochemical recycling technologies. This study introduces a scalable mechanical method to synthesize a metal-acid bifunctional catalyst. The mechanical ball milling process not only exposes more acidic sites but also enhances metal-acid proximity without blocking the pores. By varying the metal-acid balance (MAB) through different mixing ratios, we achieved higher yields and selectivity for soluble products at the optimal MAB level. Under mild conditions (250°C) for 8 h, polyethylene (PE) is efficiently converted into liquid phase iso-paraffins with an isomer selectivity of up to 56 % in the diesel and aviation kerosene fractions (C11-C18). This research underscores the importance of the accessibility of acidic sites to long-chain macromolecules, metal-acid site distance, and their balance in the hydrocracking of PE. It provides valuable theoretical insights and catalytic strategies for converting waste PE plastics into high-value fuel fractions.

Mechanochemical Synthesis of High-Entropy MOF-74 with Multiple Active Sites for CO2 Adsorption and Synergistic Conversion.

Compared with monometallic metal-organic frameworks (MOFs), the synergistic effect of multiple metals significantly enhances the catalytic performance of the CO2 cycloesterification reaction, leading to improved CO2 adsorption and catalytic conversion capabilities. To investigate this concept, a high-entropy MOF-74 (HE-MOF-74) with a uniform distribution of five distinct metal ions (Zn2+, Mg2+, Ni2+, Co2+, and Cu2+) was successfully synthesized using a straightforward mechanical ball milling technique and comprehensively characterized (including structural, morphological, and physicochemical properties). The results reveal that HE-MOF-74 exhibits significantly increased specific surface area and CO2 adsorption capacity compared with those of monometallic MOF-74. The presence of multiple unsaturated metal centers as Lewis acid sites, oxygen atoms linking the metals, and ligand-based hydroxyl groups serving as base sites enable efficient immobilization of CO2 into cyclic carbonate. This study introduces a novel synthetic approach for the green and efficient production of HE-MOF-74 and proposes a new application for CO2 utilization.

Mechanical (ball milling) activation to regulate microstructure of κ-carrageenan and improve freeze-thaw stability of κ-carrageenan gels and κ-carrageenan-based emulsion gels

To expand the wide range of applications of κ-carrageenan in the food and biomedical fields, we have physically modified the carrageenan and focused on its freeze-thaw stability. In this study, κ-carrageenan (KC) was modified by mechanically activated to prepare wet ball milling κ-carrageenan (WMKC), and its properties were determined. The research results indicate that mechanical activation helps improve the freeze-thaw stability of KC gels and enables KC to better maintain its gel network structure during the freeze-thaw process. These phenomena are related to the effects of mechanical activation on the particle morphology, molecular structure, molecular interactions, and moisture migration of κ-carrageenan. The particle morphology images demonstrated that the WMKC particles exhibited a more irregular surface, which facilitated greater penetration of water molecules into the interior of the κ-carrageenan particles. Furthermore, the results of molecular structure and molecular interaction analyses showed that mechanical activation resulted in the removal of sulfate groups from the κ-carrageenan molecular chain. This resulted in more free -OH being exposed on the molecular chain, which in turn provided more binding sites for KC molecules with water molecules. Low-field nuclear magnetic resonance (LF-NMR) results also proved that WMKC could better maintain the binding with water molecules during the freeze-thaw process. A better combination of WMKC molecules and water molecules can significantly diminish the irreversible damage to the gel network structure of WMKC during the freeze-thaw process, thereby effectively enhancing the freeze-thaw stability of WMKC. In addition, we further used WMKC as the gel matrix and investigated that the freeze-thaw stability of the WMKC-based emulsion gel was optimal when the mechanical activation duration was 3h, which well meets the demand of κ-carrageenan emulsion gels in the frozen food industry.

Upcycling Spent Graphite from Li-ion Batteries into Cu/Expanded Graphite Composites as high-performance electromagnetic wave absorbers.

With the widespread adoption of lithium-ion batteries and modern electronic components in both daily life and industrial production, there is a growing focus on the high-value recycling of spent lithium-ion batteries and the development of absorbents with high electromagnetic wave absorption capabilities. Efficiently regenerating recycling graphite from spent batteries through low-cost methods and utilizing it to prepare high-performance electromagnetic wave absorbing materials holds significant importance in addressing both the utilization of waste graphite and electromagnetic pollution issues simultaneously. This work presents a method to transform spent graphite into expanded graphite with a three-dimensional conductive structure using an enhanced Hummer's treatment and thermal reduction process. Subsequently, Cu/EG composite materials were efficiently prepared through straightforward mechanical ball milling and calcination. The unique honeycomb-like porous structure of expanded graphite facilitates the reflection and scattering of electromagnetic waves, electron transfer, and defect polarization. Additionally, the incorporation of copper nanoparticles improves the conduction loss and enhances interface polarization, allowing for precise tuning of the composite material's absorption performance. The results demonstrate that Cu/EG composite materials exhibit excellent electromagnetic wave absorption performance. The Cu/EG(1:3) sample exhibits effective absorption in the C, X, and Ku bands, achieving a minimum reflection loss (RLmin) of -54 dB and a maximum effective absorption bandwidth (EABmax) of 5.28 GHz. This performance is attained with a thickness of just 2.2 mm and a filler content of only 15 wt.%.

Research on the modification of magnesium hydride by two-dimensional layered Mo2Ti2C3 MXene

One of the most important technologies for the sustainable development of energy in the future is solid-state hydrogen storage. This study employed etching methods to fabricate two-dimensional layered catalyst Mo2Ti2C3 MXene, which was compared with unetched MAX phases Mo2Ti2AlC3 and Ti3C2, as well as Mo2C. Through mechanical ball milling, these materials were mixed with MgH2 to prepare composite materials, including MgH2 + Ti2C3, MgH2 + Mo2C, MgH2 + Mo2Ti2AlC3, and MgH2 + Mo2Ti2C3. According to the study, Mo2Ti2C3 demonstrates the synergistic catalytic actions of Ti and Mo in contrast to Ti2C3 and Mo2C. The composite material MgH2 + Mo2Ti2C3 lowers the initial dehydrogenation temperature of MgH2 to 180 °C, which is 165 °C lower than pure MgH2. After 30 min at 250 °C, the dehydrogenation amount is approximately 5.85 wt%. Hydrogen absorption begins at 40 °C and reaches approximately 5.75 wt% at 150 °C. Additionally, it maintains a reversible hydrogen storage capacity of up to 96 % even after 20th cycles at 300 °C. This is because Mo2Ti2C3 has one less layer of Al than Mo2Ti2AlC3, which results in a wider interlayer spacing, more active sites for MgH2, and facilitates hydrogen molecule dissociation and recombination.

Solid-state vitrification of LiPO3 through mechanical milling

A novel glass state of LiPO3 was obtained in powders produced by mechanical planetary ball milling of the crystal phase, in a direct room temperature solid-state process. X-ray diffraction shows that the amorphization develops through the compression along the [2 0 2] direction. This new material shows the calorimetric signatures of the glass state (glass transition and crystallization), and is produced in an excited state relaxing the excess of enthalpy through an exothermic event below the glass transition, akin to bulk glasses produced by hyperquenching of their melts. 31P nuclear magnetic resonance (NMR) reveals the progressive amorphization of the particles: the collapse of the resonances from P crystallographic sites and the appearance of broad resonances from amorphous domains. The nature of this glass is different from those obtained through melt-quench of bulk samples. The glass transition (Tg = 303 °C) and crystallization (Tc = 350 °C) temperatures are lower than in the melt-quenched glass (Tg = 330 °C, Tc = 379 °C). Also, 31P NMR shows a broader distribution of environments around Q2 phosphates, and higher populations of Q1 and Q3, suggesting differences in middle-range order. The amorphization can be fully reversed by recrystallization of the powders at 333 °C.

Stabilization and Remediation of Arsenic-Contaminated Soil: Fly Ash-Based Technology for Industrial Site Restoration

Arsenic contamination of various environmental components poses a serious threat to human and animal health. Soil As contamination is particularly hazardous, as soil is a vital pathway to the food chain. We conducted experiments on soil from a typical pharmaceutical and chemical industry relocation site in Hubei Province, focusing on modification using fly ash through mechanical and chemical mechanisms. We subjected varying proportions of lime, ferrous sulfate, and fly ash to mechanical ball milling and used these mixtures to perform remediation of arsenic-contaminated soil and site restoration. Our findings are as follows: in soil culture experiments, the As stabilization efficiency reached 90% within 90 days with ferrous salt-modified fly ash. In actual site restoration, As-stabilization efficiency exceeded 95% across different soil depths within 30 days, demonstrating significant stabilization effects. Optimal modified dosages were determined as 2% ferrous sulfate and 2% fly ash. After stabilization, As in the soil primarily existed in amorphous iron-aluminum oxide-bound (F3) and crystalline iron-aluminum oxide-bound (F3 + F4) and residual (F5) states. Fluctuations in the moisture content and pH mainly activated F3 and F4, transitioning them into exchangeable (F1) and surface-adsorbed (F2) states. Arsenic leaching was predominantly associated with the F1 form. Fly ash-based restoration technology demonstrates promising capabilities in waste treatment and pollution control, offering significant potential for widespread application.

Preparation of nano magnesium oxide by mechanochemical method using magnesium chloride

Magnesium chloride is a magnesium resource that is widely present in seawater and salt lakes. Therefore, the use of magnesium chloride is of great significance for the low-cost preparation of high-performance magnesium materials. In this work, mechanical ball milling was used for the preparation of magnesium oxide nanoparticles from magnesium chloride. Ball milling improves the unevenness of the reaction process and generates magnesium oxide with a more uniform particle size distribution. First, a magnesium chloride complex was obtained by heating and evaporating a mixture of magnesium chloride and ethanol with a mass ratio of 1:2 at 110 °C. Next, pure magnesium hydroxide with a smaller crystal size was obtained by ball milling the prepared magnesium chloride complex with calcium hydroxide at 600 rpm for 3 h. Finally, the magnesium hydroxide was calcined at 1000 °C for 60 min to obtain nano magnesium oxide particles with a particle size of 670 nm.

Design and preparation of carbon-coated NaZnFe(MoO4)3 composite as novel anode materials for lithium/sodium-ion batteries

The investigation of new anode materials with novel crystal structure and high ionic conductivity is of great significance for potential applications in lithium/sodium-ion batteries. Herein, carbon-coated NaZnFe(MoO4)3 composite was produced by solid state method coupled with the mechanical ball milling technique. The crystal and morphology were accurately confirmed by XRD, XPS and SEM techniques. When tested with lithium-ion batteries, the charging capacity reached an impressive 1005 mA h g−1 during the initial cycle and 840 mA h g−1 after 50 cycles, resulting in a capacity retention of 84.2 %. This performance is 40 % higher than that of the sample without a carbon layer coating. When utilized as an anode for sodium-ion batteries, the carbon-coated NaZnFe(MoO4)3 composite electrode exhibited a remarkable specific capacity of 152 mA h g−1 and a high capacity retention of 74.9 % after 100 cycles at a rate of 100 mA g−1. Furthermore, the charge capacity was measured at 105 mA h g−1 after 500 cycles test conducted at 500 mA g−1, with a capacity retention of 86.0 %. The advantages of polyanionic molybdate NaZnFe(MoO4)3 combined with the simple carbon coating strategy make it possible to application in the next generation of Li/Na secondary batteries.

Preparation of carbon nanotube composite solder and analysis of the thermal properties

Abstract The solder layer constitutes a crucial component of IGBT power modules. It endures significant thermal stress during operation, and the magnitude of this stress correlates with the coefficient of thermal expansion. To prevent fatigue damage to the solder layer during operation, it is necessary to reduce the solder’s coefficient of thermal expansion, thereby alleviating the impact of thermal stress. In this paper, the method of adding carbon nanotube powder to solder is proposed to solve this problem. Firstly, the relationship between thermal stress and the coefficient of thermal expansion is analyzed, and then the mechanical ball milling method is employed to prepare composite solder with a 0.05% carbon nanotube content. Scanning electron microscopy observation of the prepared composite solder reveals homogeneous mixing and uniform distribution of carbon nanotubes on the solder particle surfaces. Furthermore, thermal expansion coefficient tests were conducted on the sintered carbon nanotube composite solder, revealing a 16.2% reduction in the coefficient due to the incorporation of carbon nanotubes.

Wet ball milling activated oyster shells for multifunctional slow-release compound fertilizer production

Slow-release fertilizers have been known to boost crop yields, but their high cost and slow degradation make them less practical for use. In this study, oyster shell (OS) was modified by mechanical ball milling with monosodium glutamate (MSG) wastewater as an activator to prepare activated oyster shell (AOS) with an average particle size of 32.7 nm. Compared to natural oyster shell (NOS), the AOS increased water-soluble Ca by 22 times, expanded the average desorption pore size by 155 %, enhanced the specific surface area by 9 times, and improved the total pore volume by 1587 %. AOS was mixed with traditional fertilizers and extruded to develop a new type of activated oyster-based slow-release compound fertilizer (AOF). Physical effects mainly controlled the slow-release ability of AOF. AOS formed vaterite with a large peak shape, high strength, and well-defined crystal structure, providing more binding sites for NH4+, HPO42−, K+, Ca2+ and Mg2+. In addition, AOS was rich in Ca-OH and Mg-OH, which increased the potential for ligand exchange with fertilizer ions, which further improved the chemical slow-release properties of AOF. The AOF continuously releases N, P, K, Ca, and Mg nutrients over a period exceeding 70 days. The nutrient release behavior in AOF was accurately described by the logistic equation, the Elovich equation, and the parabolic diffusion equation. AOF increased the dry weight of green plum by 190 % and the yield by 61 %. The AOF prepared in this study proved to be an innovative and environmentally sustainable slow-release fertilizer.

Carbon coating engineering enhances the stability of graphite anode in potassium ion batteries

Graphite forms reversible potassium-graphite intercalation compounds electrochemically. Graphite anode possesses a high reversible specific capacity (279 mAh g−1) and an optimal low potential platform, rendering it an ideal anode material for potassium-ion batteries. However, the intercalation of K+ ions in graphite causes a bulk volume expansion of up to 61%, resulting in irreversible damage to the structure of graphite, which leads to inferior cycling stability. In this paper, surface-oxidized graphite (OG) with reduced particle size and increased defect densities was obtained by mechanical ball milling and chemical oxidation. Composites of soft carbon-coated OG (OG@PC) were prepared by soft carbon coating. The soft carbon coating can alleviate the bulk expansion caused by K+ intercalation/deintercalation in OG, thus slowing down the destruction of the crystalline structure of graphite after multiple charging/discharging cycles. OG@PC exhibits increased reversible specific capacity from 267 mAh g−1 to 314 mAh g−1 compared with pristine graphite at a current density of 0.05 A g−1. Moreover, at a high current density of 0.5 A g−1, a reversible specific capacity of 213 mAh g−1 was achieved after 200 cycles. This work investigates simple surface carbon coating strategies to improve the cycling stability of a graphite anode of potassium-ion batteries.

Investigation on the hydrogen absorption and dissociation properties of ball milling CeMg12/Ni/NbF5 type alloy for emergency power supply of fuel cell for meteorological radar station

In this article, in order to investigate the mechanism of action of catalysis on the hydrogenation and dehydrogenation properties of CeMg12-type alloy, the catalysis Ni and NbF5 was been added to prepare the CeMg12/Ni/NbF5 composite materials during ball milling treatment. The results in term of microstructure indicate that part of NbF5 is transformed into low valence NbF4 and helpful for forming MgF2 phase after ball milling treatment, which is advantageous for ameliorating the hydriding and dehydriding performances of experimental alloy. The results of the study from the perspective of hydrogen absorption and desorption performance test show that the increasing NbF5 decreases the enthalpy-value for hydrogen release and the platform pressure for the process of hydrogen releasing of ball-milled alloy, which is good for improving the hydrogen release performance of the alloy. The addition of a certain amount of NbF5 can effectively upgrade the kinetics of hydrogen dissociation of CeMg12-type alloy treated through mechanical ball milling. The alloy with 6 wt.% NbF5 has the best kinetic performance of hydrogen release, corresponding to activation energy can be reduced from 90.86 kJ/mol (0 wt.% NbF5) to 86.41 kJ/mol(6 wt.% NbF5).

Effect of ball milling activation on CO2 mineralization performance in fly ash and fire resistance capabilities of mineralized product

Coal-fired power generation has always been a major energy supply source globally. However, a large amount of CO2 is emitted with the combustion of coal resources, and fly ash, a by-product of coal combustion, is also accumulated in large quantities. The application of CO2 mineralization in fly ash can not only reduce CO2 emission but also effectively manage industrial waste, thereby promoting environmental sustainability. This paper used the mechanical ball milling method to activate fly ash and investigated the effects of ball milling time and speed on the CO2 sequestration in fly ash. At 30 min ball milling time and 400 r/min ball milling speed, the modified fly ash achieves a good CO2 sequestration capacity of 81.70 gCO2/kgFA. Compared with raw fly ash, the CO2 consumption of treated fly ash is higher at 75.41 mmol/mL. The specific surface area and pore volume of treated fly ash are larger at 1.57 m2/g and 4.33 cm3/kg respectively, which is beneficial for enhancing mass transfer capacity and the carbonation effect. As the ratio of mineralized product/coal increases from 0.5 to 4, the crossing-point temperature increases from 157.20 °C to 165.15 °C. Based on the experimental results, the paper discussed the mechanism of ball milling activation to enhance the carbonation effect of fly ash. This study provides theoretical references for the environmentally friendly utilization of fly ash.