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A series of composites was prepared starting from five types of LDHs, which were then exchanged with three types of metallo-phthalocyanines, and, in the end, magnetic nanoparticles were attached. In the case of LDHs containing Fe, characterization data showed that there was a partial oxidation from Fe2+ to Fe3+. Samples containing evident LDH structures performed better in general than the ones containing iron oxide mixtures, the composites being more active towards amoxicillin removal compared with ampicillin removal. The nature of the phthalocyanine did not have such a great influence, although some differences in the activity were observed. The removal was a combination between adsorption and photocatalytic degradation. The best composites for this application were those based on Mg0.325Fe0.325Al0.25-LDH prepared by co-precipitation in the presence of NaOH and Na2CO3. They presented high adsorption capacity in 10 min and, at the same time, high photocatalytic activity for both amoxicillin and ampicillin. [ABSTRACT FROM AUTHOR]

α‐halo alkylboronic esters, acting as ambiphilic synthons, play a pivotal role as versatile intermediates in fields like pharmaceutical science and organic chemistry. The sequential transformation of carbon–boron and carbon–halogen bonds into a broad range of carbon–X bonds allows for programmable bond formation, facilitating the incorporation of multiple substituents at a single position and streamlining the synthesis of complex molecules. Nevertheless, the synthetic potential of these compounds is constrained by limited reaction patterns. Additionally, the conventional methods often necessitate the use of bulk toxic solvents, exhibit sensitivity to air/moisture, rely on expensive metal catalysts, and involve extended reaction times. In this report, a ball milling technique is introduced that overcomes these limitations, enabling the external catalyst‐free multicomponent coupling of aryl diazonium salts, alkenes, and simple metal halides. This approach offers a general and straightforward method for obtaining a diverse array of α‐halo alkylboronic esters, thereby paving the way for the extensive utilization of these synthons in the synthesis of fine chemicals. [ABSTRACT FROM AUTHOR]

To fabricate metals from the base materials for future Mars exploration, synthesis of representative olivine phases and their structural and spectroscopic characterizations are of crucial importance. Using mechanochemical technique that mimics the mechanical weathering, a complete solid solution of (Mg1−xFex)2SiO4 has been synthesized to investigate the associated crystal chemical properties. X-ray powder diffraction data Rietveld analysis confirms that each polycrystalline sample crystallizes in space group Pbnm. The average crystallite size ranges between 80(1) nm and 223(4) nm. Each lattice parameter increases with increasing Fe-content due to the larger Fe2+ radius than that of Mg2+, following Vegard's rule. For a given nominal chemical composition, substitution of Mg with Fe at the M1-site (4a: 0,0,0) is preferred to the M2-site (4c: x,y,¼). As a consequence, the average Fe-content lies slightly below the equivalence line for x = 0.2–0.8, indicating that the Fe/Mg ratio in the amorphous scattering content is most likely greater than unity. Characteristic Raman spectral features of the olivines have been explained in terms of the chemical composition (x). Simple regression models are demonstrated based on both X-ray diffraction and Raman spectroscopic data for the calculation of Mg/Fe in olivines. Diffuse reflectance UV/Vis spectra RATD analysis shows each olivine phase possesses direct band-gap between 3.38(3) eV and 4.90(3) eV. This study could keep valuable information to relevant databases for future human missions on Mars, in particular, for precise estimation of the representative olivines from the remote X-ray diffraction and spectroscopic data. [ABSTRACT FROM AUTHOR]

The removal of hexavalent Cr from water is vital considering its harmful and carcinogenic effects on human health as well as the environment. Effective exclusion of Cr(VI) provides reliable water to consume, impedes bioaccumulation, and mitigates environmental pollution.The present work details the rapid, ecofriendly, solvent-free mechanochemical route for the development of a polymeric Schiff-Base-wrapped TiO2 (SBP@TiO2) nano-adsorbent for the effective removal of Cr(VI) from water. The comprehensive understanding of the structural and chemical characteristics of the newly synthesized materials were examined through Fourier transform infrared (FTIR) spectroscopy, X-Ray Diffraction (XRD), and Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) spectroscopy. To assess the adsorption capacity, kinetics, and equilibrium of Cr(VI) adsorbate on adsorbent material (TiO2 and SBP@TiO2) and to understand the interplay between the critical parameters and their impact on adsorption, a series of batch adsorption studies were carried out. The adsorption equilibrium data for the Cr(VI) adsorption process fitted well with the Freundlich isotherm model of adsorption and adsorption kinetics disclosed that the data are in excellent agreement with R2 values of 0.98721 for the pseudo-second-order, indicating that the sorption process is by chemisorption. Thermodynamic measurements revealed that the adsorption of Cr(VI) on SBP@TiO2 was spontaneous and endothermic, as corroborated by the −ve value of ΔGo and the +ve value of ΔHo, respectively. It was discovered that the sorption of 10 and 50 ppm of Cr(VI) on SBP@TiO2 was 96% and 75.4% under optimal conditions, respectively. In contrast, the sorption study of Cr(VI) on TiO2 under identical conditions was found to be 49%. The study found that surface functionalization of TiO2 by SBP admirably improved the adsorption capacity, signifying SBP@TiO2 as an efficient Cr(VI) adsorbent.

Here we demonstrated a solvent free, mechanochemical I2 catalyzed C(sp2)–H sulfenylation of enaminones under grinding condition. Only catalytic amount of I2 is required on silica surface without any external heating. The reaction time has reduced to a great extent in comparison to their solution based counterpart. The frictional energy created by ball-mill on mesoporous silica materials has attracted much attention towards this mechanochemical approach for molecular heterogeneous catalysis. Their large surface area and well defined porous architecture certainly increase the catalytic ability of iodine in this developed protocol. Anti-microbial activities of our synthesized compounds were investigated against two gram positive (Staphylococcus aureus and Bacillus cereus) and two gram negative (Escherichia coli and Klebsiella pneumonia) bacteria. To understand the potency of these compounds (3a–3m) as antimalarial agents, molecular docking studies were also performed. Density functional theory was also used to investigate the chemical reactivity and kinetic stability of the compound 3a–3m. [ABSTRACT FROM AUTHOR]

The innovative work shows a new strategy to modify the physicochemical properties of medicines and improve patients' lives. The mechanochemical synthesis and characterization of the first Norfloxacin nanocrystal are described. In recent decades, nanotechnology has gained significant attention in the scientific field through the study of the design, formation and application of materials at the nanoscale level. In the pharmaceutical sector, nanotechnology has been the focus of studies on systems that allow increased bioavailability. The present work investigated the formation of pharmaceutical nanocrystals. Nanocrystals are crystalline nanoparticles ranging in size from a few nanometers to 1,000 nm, composed of 100% of the drug and stabilized by surfactants or polymeric stabilizers. They have a safe formulation and are well tolerated compared to conventional medicines. The drug used in this study was Norfloxacin, a broad-spectrum antibiotic that has low bioavailability. Several nanocrystallization techniques are found in the literature, among which the mechanochemical method stands out. Mechanochemistry is an approach that allows the reduction of particle size through the mechanical energy provided in the reaction medium. Thus, it was possible to obtain nanomaterials and explore the influence of surfactants in controlling the particle size and morphology of the materials obtained.

Abstract α‐halo alkylboronic esters, acting as ambiphilic synthons, play a pivotal role as versatile intermediates in fields like pharmaceutical science and organic chemistry. The sequential transformation of carbon–boron and carbon–halogen bonds into a broad range of carbon–X bonds allows for programmable bond formation, facilitating the incorporation of multiple substituents at a single position and streamlining the synthesis of complex molecules. Nevertheless, the synthetic potential of these compounds is constrained by limited reaction patterns. Additionally, the conventional methods often necessitate the use of bulk toxic solvents, exhibit sensitivity to air/moisture, rely on expensive metal catalysts, and involve extended reaction times. In this report, a ball milling technique is introduced that overcomes these limitations, enabling the external catalyst‐free multicomponent coupling of aryl diazonium salts, alkenes, and simple metal halides. This approach offers a general and straightforward method for obtaining a diverse array of α‐halo alkylboronic esters, thereby paving the way for the extensive utilization of these synthons in the synthesis of fine chemicals.

Electrocatalysis serves as a highly effective approach to both mitigate greenhouse gas emissions and produce high-value chemicals. Copper-based catalysts have garnered considerable attention due to their immense potential in this domain. Improving the selectivity and activity through optimizing preparation strategies is of paramount importance. In this study, the mechanochemical method was first used for preparing copper-based composite metallic oxide electrocatalysts. Spherical CuO, Sn-CuO, and Sn-In-CuO catalysts were prepared, and their electrochemical CO2 performance was evaluated. Among them, the Sn-In-CuO catalyst demonstrated the best performance in reducing CO2 to CO products. Within the potential range of −0.6 V to −1.1 V vs. RHE, the Faradaic efficiency of the CO product was consistently above 93.56%, with a maximum Faradaic efficiency of 96.11% achieved at −0.9 V vs. RHE. Sn-In-CuO also exhibits good stability with high Faradaic efficiency of CO above 87.97% for a duration of 6 h under the potential of −0.6 V vs. RHE in a 0.1 M KHCO3 electrolyte. The excellent performance is speculated to be attributed to the generation of a large number of defects and the introduction of metal doping, which increases the number of active sites through the mechanochemical method. [ABSTRACT FROM AUTHOR]

Industrial-use VOx-based catalysts usually have a higher active temperature window (> 250-300°C), which becomes a "bottleneck" for the practical application of PCDD/Fs catalytic degradation technology. In this work, VOx-FeOx/TiO 2 catalyst prepared via mechanochemically method was investigated for the catalytic removal of PCDD/Fs. The removal efficiency of 1,2-DCBz, pure PCDD/Fs gas generated in the lab, PCDD/Fs from actual flue gas, long-term were studied, and the degradation mechanism was explored using FTIR and TOFMS. The degradation efficiency of 1,2-DCBz and PCDD/Fs on VOx-FeOx/TiO 2 were higher than that of VOx/TiO 2 catalyst, and the optimal FeOx addition ratio was 3 wt.%. The characterization results show that the addition of FeOx can effectively improve the pore structure, surface acidity, and VOx dispersion of the catalyst, thus contributing to increasing the V5+ content and surface-active oxygen, which is conducive to the improvement of adsorption and redox performance of the catalyst. Under the actual MSWI (municipal solid waste incineration) flue gas, the PCDD/Fs removal efficiency over VTi-3Fe-MC maintained long-term stability, higher than 85% for 240 min. This result was not significantly reduced compared with the data obtained in the laboratory. According to the analysis results of intermediate products by FTIR and GC-TOFMS, it can be inferred that the epoxidation fracture of benzene ring is the rate-limiting step of dioxin catalytic degradation reaction. This work gives an in-depth view into the PCDD/Fs removal over VOx-FeOx/TiO 2 catalysts and could provide guidelines for the rational design of reliable catalysts for industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Currently exploited iron ores have high-manganese content. Conventional leaching of manganese takes about 2 h at 80 ̊C followed by precipitation. Thus, it consumes high energy and a relatively long-time. In this paper, the mechanochemical method was investigated for reducing manganese in iron ore at a shorter time and at room temperature. The number and size of balls were studied during the milling process in the presence of sulfuric and/or oxalic acid either as a single acid or as a mixture. The higher the ball's number and size the higher the iron and manganese dissolution. The sulfuric-oxalic acid mixture is better than the usage of single acid for reducing the manganese at about 10 min. The iron concentrate, containing 54% Fe and 2.9% Mn from a feed containing 57% Fe and 7.5% Mn, is obtained using 15 balls of size 3.3 cm and 2%:4% sulfuric to oxalic ratio and dosage. Moreover, the mechanochemical is advantageous over conventional leaching as it continuously cleans the surface, creates new surfaces, controls iron dissolution, is conducted at room temperature and shorter time (about 10% of the time needed for the leaching process), and direct production of iron concentrate without subsequent processes like precipitation. [ABSTRACT FROM AUTHOR]

Urea cocrystal materials are a potential fertilizer source that has shown to decrease environmental nitrogen losses. Novel nitrogen (N)-containing urea cocrystal fertilizers, CaSO4·4urea (UC1) and Ca(H2PO4)2·4urea (UC2), were synthesized using the mechanochemical method to form stable urea cocrystals to be tested as a fertilizer source for turfgrass. The objectives of this study were to 1) evaluate the response of ‘Tifway’ hybrid bermudagrass (Cynodon dactylon × C. traansvalensis Burt Davy) to N fertilization by urea cocrystals and traditional coated urea products (MU·PCU, methylene urea, urea, polymer-coated urea; PCU, polymer-coated urea, urea) supplied at two rates at the beginning of two, 10-week study periods conducted under a greenhouse setting and 2) investigate N release behavior of urea and two cocrystal products using a rapid water release test. In the turfgrass response study conducted in the greenhouse, improved turfgrass quality above the minimum quality threshold was observed when averaging across all products. For normalized difference vegetation index (NDVI), cocrystal outperformed all other products in the summer study and both cocrystal products outperformed the traditional product (MU·PCU) in the winter study. Further, both cocrystal products showed favorable growth responses compared with the commercial products provided by positive clipping production and vertical extension rates. In the nitrogen release experiment, a rapid water release test revealed the N release peak of urea was significantly higher than both UC1 and UC2. Furthermore, significantly higher N was leached from urea (15% loss) compared with both UC1 and UC2 (≈8% loss). Results from both studies provide evidence supporting suitability of urea cocrystal application on bermudagrass and potential as a slow-release fertilizer source through sustained turfgrass vigor, growth, decreased N release peak, and decreased leaching losses.

In the present work, we developed an experimental class for undergraduate students concerning the linear synthesis of 2-phenylimidazo[1,2-α]pyridine through mechanochemical techniques. This approach aims to conceptualize the green chemistry principles through a safe, robust, atom-economic, energy-efficient, and solvent-free method for preparing these classes of compounds by manual grinding and vortex mixing. The methodology was easily applied in experimental classes for chemistry students and could be easily expanded to other courses such as pharmacy and biotechnology.

Herein, a mechanochemical approach was developed for recover the cobalt and from spent lithium-ion batteries using a high-concentration chloride solution. Effect of parameters on the leaching efficiency of cobalt was studied. 97, 6% of Co was recovered under optimum conditions: rotation speed 500 r/min, S/L ratio: 1:150 g/ml, ball/material ratio 25:1 g/g, milling time 30 min, respectively. The dissolved cobalt was recovered by selective precipitation method to ensure that the recycled Co can be reused for lithium-ion battery production. This research presents a highly efficient and environmentally friendly approach for recovering cobalt from spent LiBs. [ABSTRACT FROM AUTHOR]

Metal Organic Framework (MOF) is a material that serves as a photocatalyst for decomposing methylene blue pollutant. MOF can be constructed using several kinds of synthetic methods. This study aims to determine the alternative efficient and eco-friendly synthesis method of isonicotinic acid-modulated chromium perylene 3,4,9,10-tetracharboxylate MOF (Cr-PTC-HIna) using solvothermal, hydrothermal, sonochemical, and mechanochemical methods. FTIR analysis revealed that Cr-PTC-HIna was successfully fabricated only by solvothermal, hydrothermal, and sonochemical methods, yielding 40.68%, 44.27%, and 46.50%. Cr-PTC-HIna-ST, Cr-PTC-HIna-HT, and Cr-PTC-HIna-SC have band gap energies of 2.02, 2.02, and 1.98 eV, respectively. Cr-PTC-HIna-HT and Cr-PTC-HIna-SC with irregular shapes form agglomerations. Cr-PTC-HIna-SC had the highest surface area, pore volume, and pore size of 92.76 m2.g−1, 0.3947cm3.g−1, and 142.74 nm, respectively. Cr-PTC-HIna-SC has the highest percentage of methylene blue decolorization through adsorption of 61.843% and photocatalytic degradation of 25.635%. Sonochemical and hydrothermal showed potential as more eco-friendly methods than solvothermal in synthesizing Cr-PTC-HIna MOF. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Herein, a mechanochemical approach was developed for recover the cobalt and from spent lithium-ion batteries using a high-concentration chloride solution. Effect of parameters on the leaching efficiency of cobalt was studied. 97, 6% of Co was recovered under optimum conditions: rotation speed 500 r/min, S/L ratio: 1:150 g/ml, ball/material ratio 25:1 g/g, milling time 30 min, respectively. The dissolved cobalt was recovered by selective precipitation method to ensure that the recycled Co can be reused for lithium-ion battery production. This research presents a highly efficient and environmentally friendly approach for recovering cobalt from spent LiBs.

This study addressed the formation of co‐crystals from Quercetin and Curcumin by mechanochemical treatment employing ball mill grinding. The binary system was initially studied using molecular complementarity and hydrogen bond propensity analysis structural tools available in Mercury software. This study was performed from CCDC reported structural data for Curcumin and Quercetin dihydrate used as starting reagents. Reaction conditions, such as Quercetin: Curcumin molar ratio, grinding time, and solvent‐assisted variables, were optimised to synthesise a new solid phase from the binary system. The synthesised product was characterised by differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and powder X‐ray diffraction techniques. Finally, to compare the anti‐oxidant capacities from the pure components, eutectic mixtures previously reported and the new crystalline phase was evaluated in vitro using the 1,1‐diphenyl‐2‐pycril‐hydrazylhydrate radical inhibition method. The co‐crystal phase and eutectic mixtures present higher anti‐oxidant activity with values around 5.0 mg/L compared to pure Quercetin (3,444 mg/L) and Curcumin (9,141 mg/L), using only half of the molecules. These results indicate Quercetin molecule is synergically active with the Curcumin molecule in the binary mixtures. [ABSTRACT FROM AUTHOR]

Energy storage systems (ESSs) are attracting increasing attention for the development of sustainable and renewable energy technologies owing to limited fossil fuels. Supercapacitors are gaining significant interest as energy storage devices owing to their high-power density and long-term cycle stability. The use of suitable electrode materials affects the performance of supercapacitors. In this study, we fabricated a carboxyl-doped graphene nanoplatelet (CGnP) via a mechanochemical reaction. Additionally, CGnP was activated by controlling parameters such as temperature, flow rate, and maintenance period and evaluated as an electrode material for supercapacitors. The effect of the specific surface area (SSA) and functional groups of the fabricated samples on the capacitance was confirmed by controlling the activation parameters. The activated CGnP with 300 mL/min of CO2 at 1173 K for 4 h exhibited a high SSA of 1300 m2/g. The activated CGnP (180 F/g), with a high SSA, showed an increased capacitance of 46% compared to pristine CGnP (123 F/g). Additionally, activated CGnP1100 demonstrated good wettability and exhibited excellent stability with a low capacitance decrease of 6.1%, even after 10,000 cycles. [ABSTRACT FROM AUTHOR]

The low-temperature formation of dolomite (CaMg(CO3)2) is undoubtedly a long and interesting geological problem, which has troubled many researchers for centuries to explore the formation of dolomite. Recently, efforts have been made by synthesizing dolomite analogues such as norsethite (BaMg(CO3)2), PbMg(CO3)2, with Ba and Pb to replace Ca and investigating their reaction pathways. In this study, we reported our efforts to synthesize dolomite-related complex carbonates by using the mechanical ball milling method as a new approach to control the solid–water ratio compared to the commonly used solution method. Two analogues of norsethite and PbMg(CO3)2 have been simply obtained even at stoichiometric molar ratio of Ba/Mg = 1:1 and Pb/Mg = 1:1 with various parameters examined; and product properties including morphology and phase compositions were investigated by a range of techniques, including XRD, SEM-EDS, and FTIR. Finally, we attempted to synthesize dolomite and compared the differences from the synthesis of analogues. In conclusion, we have synthesized norsethite and PbMg(CO3)2 in one step by the ball milling method, which greatly reduces the reaction time compared with the conventional solution method and may provide other choices for the formation of dolomite. [ABSTRACT FROM AUTHOR]

A new approach was developed to prepare NaZr2(PO4)3 (NZP) powders at low temperature of 330°C. The effect of different molar ratios of ZrO(NO3)2 • xH2O to NaH2PO4 • 2H2O on the synthesis of NZP powders was systematically investigated by XRD, FE-SEM, TEM, EDS and Raman spectroscopy. The mineralizer NaNO3 was formed in situ due to the mechanochemical reaction between raw materials ZrO(NO3)2 • xH2O and NaH2PO4 • 2H2O during the grinding process. When the optimal molar ratio of Zr:P = 2:6 was used, the NZP powders with high crystallinity, good dispersity and particle sizes in the range of 500-700 nm were obtained. The dense NZP ceramics was obtained by sintering at 1100 °C for 3 h with 2 wt.% ZnO as the sintering aid. The relative density and Vickers hardness of the sintered ceramics reached 93.4% and 704MPa, respectively.

Metal Organic Framework (MOF) is a material that serves as a photocatalyst for decomposing methylene blue pollutant. MOF can be constructed using several kinds of synthetic methods. This study aims to determine the alternative efficient and eco-friendly synthesis method of isonicotinic acid-modulated chromium perylene 3,4,9,10- tetracharboxylate MOF (Cr-PTC-HIna) using solvothermal, hydrothermal, sonochemical, and mechanochemical methods. FTIR analysis revealed that Cr-PTC-HIna was successfully fabricated only by solvothermal, hydrothermal, and sonochemical methods, yielding 40.68%, 44.27%, and 46.50%. Cr-PTC-HIna-ST, Cr-PTC-HIna-HT, and Cr-PTC-HIna-SC have band gap energies of 2.02, 2.02, and 1.98 eV, respectively. Cr-PTC-HIna-HT and Cr-PTCHIna-SC with irregular shapes form agglomerations. Cr-PTC-HIna-SC had the highest surface area, pore volume, and pore size of 92.76 m².g−1, 0.3947cm³.g−1, and 142.74 nm, respectively. Cr-PTC-HIna-SC has the highest percentage of methylene blue decolorization through adsorption of 61.843% and photocatalytic degradation of 25.635%. Sonochemical and hydrothermal showed potential as more eco-friendly methods than solvothermal in synthesizing Cr-PTC-HIna MOF. [ABSTRACT FROM AUTHOR]

The reaction of methane decomposition is an endothermic process that produces hydrogen without any impurities as a gas product and carbon nanotubes/carbon nanofibers as a solid product. In this study, NiO–MgO catalysts with different nickel loadings (20, 30, 40, and 50 wt. %) were synthesized using the mechanochemical method. The Physicochemical features of the synthesized catalysts were characterized by various methods such as BET, XRD, SEM, TPO, and H2-TPR. The prepared samples were tested in the methane decomposition process at various temperatures under the GHSV value of 48,000 ml/(gcat h). Among the prepared samples, the 50wt.%NiO–MgO exhibited the best activity (40% methane conversion at 575 °C) in this process due to its higher concentration of active metal and better catalyst reducibility. Also, the effect of different parameters such as feed ratio, GHSV, and calcination temperature was studied on the activity of this catalyst. The results showed that with the increase of GHSV and feed ratio, the methane conversion decreased due to the lesser contact time and diminishing the proportion of accessible active sites per methane entrance molecules. Moreover, the results showed that with the rise of calcination temperature from 500 to 700 °C, the methane conversion decreased due to the sintering of nickel particles. The results also showed that the addition of 15 wt.% Cr2O3 to the catalyst formulation improved the catalytic performance and lifetime in the thermocatalytic decomposition of methane due to the higher reducibility and dispersion of the active species on the catalyst surface. [ABSTRACT FROM AUTHOR]

In the present work the two new Cu(II) complexes, (µ-acetato)-bis(2,2′-bipyridine)-copper [Cu(bpy)2(CH3CO2)] and bromidotetrakis(2-methyl-1H-imidazole)-copper bromide [Cu(2-methylimid)4Br]Br have been synthesized by liquid assisted mechanochemical method. The [Cu(bpy)2(CH3CO2)] complex (1) and [Cu(2-methylimid)4Br]Br complex (2) characterised by IR and UV–visible spectroscopy and the structure are confirmed by XRD diffraction studies. Complex (1) crystallized in the Monoclinic with the space group of C2/c where a = 24.312(5) Å, b = 8.5892(18) Å, c = 14.559(3) Å, α = 90°, β = 106.177(7)° and γ = 90° and Complex (2) crystallized in the Tetragonal with the space group of P4nc, a = 9.9259(2) Å, b = 9.9259(2) Å, c = 10.9357(2) Å, α = 90°, β = 90° and γ = 90°. The complex (1) has distorted octahedral geometry where the acetate ligand showed bidentate bridging with the central metal ion and complex (2) has slightly deformed square pyramidal geometry. The HOMO–LUMO energy gap value and the low chemical potential showed that the complex (2) is stable and difficult to polarize compare to complex (1). The molecular docking study of complexes with the HIV instasome nucleoprotein showed the binding energy values − 7.1 and − 5.3 kcal/mol for complex (1) and complex (2) respectively. The negative binding energy values showed the complexes have affinity to bind with HIV instasome nucleoproteins. The in-silico pharmacokinetic study of the complex (1) and complex (2) showed non AMES toxicity, non-carcinogens and low honey Bee toxicity but weakly inhibit Human Ether—a-go-go-related gene. [ABSTRACT FROM AUTHOR]

Mechanochemistry afforded a photoactive cocrystal via coexisting (B)O−H⋅⋅⋅N hydrogen bonds and B←N coordination. Specifically, solvent‐free mechanochemical ball mill grinding and liquid‐assisted grinding of a boronic acid and an alkene resulted in mixtures of hydrogen‐bonded and coordinated complexes akin to mixtures of noncovalent complexes that can be obtained in solution in equilibria processes. The alkenes of the hydrogen‐bonded assembly undergo an intermolecular [2+2] photodimerization in quantitative conversion, effectively reporting the outcome of the self‐assembly processes. Our results suggest that interplay involving noncovalent bonds subjected to mechanochemical conditions can lead to functional solids where, in the current case, the structure composed of the weaker hydrogen bonding interactions predominates. [ABSTRACT FROM AUTHOR]

Freshwater generation has been extensively studied to address the global freshwater scarcity issue, although designing a simple, inexpensive system with high efficiency and sustainability is complicated. Solar‐driven water evaporation is a promising, highly efficient water purification strategy. This paper reports the synthesis of a hydrophilic conductive polymer and its carbon nanotube (CNT) composites for efficient solar‐driven water evaporation via a quick mechanochemical process. Doped polydiphenylamine (PD) and its CNT composites were obtained by the simple grinding of an inexpensive eutectic‐phase monomer with oxidants, doping agents, and oxidized CNTs. The obtained composites exhibited high photothermal efficiency (89.9%) and water evaporation rate (1.41 kg m−2 h−1) under 1 sun irradiation. Dual doping and introducing oxidized CNTs into PD enhanced the wettability, photothermal efficiency, and water evaporation performance. This study provides an effective strategy for the fast and facile fabrication of photothermal membranes for solar‐driven freshwater generation. [ABSTRACT FROM AUTHOR]

The CuMn samples with various CuO weight percentages were synthesized by the mechanochemical route. The catalytic activity of the prepared samples was determined in the preferential oxidation of CO process (CO-PROX) in the temperature range of 40–250 °C. According to the XRD results, the 5CuMn and 10CuMn samples exhibited the spinel phase in their structures. The spinel phase formation enhanced the CO adsorption active sites and modified the redox properties. The results indicated that the copper incorporation into the manganese oxide modified the catalytic activity and structural properties. The 5CuMn catalyst with the highest BET area (72.1 m2 g−1) possessed 96% CO conversion and 50% CO 2 selectivity at 70 °C (GHSV = 30,000 ml/h.g cat) and significant resistance in the presence of water due to the formation of hydroxyl groups over the catalyst surface. The catalyst activity remained stable for 14 h at 130 °C. Furthermore, the influence of calcination temperature, feed composition, and GHSV value on the catalytic performance of the 5CuMn catalyst was studied. • The Cu–Mn catalyst with 5 wt% Cu exhibited a CO conversion higher than 90% at 70 °C. • 5 wt%. CuO-MnOx showed a Cu 1.5 Mn 1.5 O 4 spinel structure. • 5 wt%. CuO-MnOx catalyst exhibited sufficient stability in the presence of water vapor. [ABSTRACT FROM AUTHOR]

A direct protocol for Rh‐catalyzed C−H amidation of ferrocenes in a ball mill using dioxazolones as the amide source under solvent‐free conditions was developed. The corresponding ortho‐aminated products were formed in 3 hours and the yields were up to 99% in the absence of base. This method could be a typically sustainable and environmental‐friendly alternative method to traditional methodologies, with the advantages of wide substrate range, good functional group tolerance and gram‐scale synthesis. [ABSTRACT FROM AUTHOR]

The discharge of anionic and cationic synthetic dyes into the environment can cause significant health and environmental problems. Adsorption is promoted as one of the efficient methods to solve this issue. In this work, a metal-organic framework, namely Materials of Institut Lavoisier-100(Cr) denoted as MIL-100(Cr), was synthesized mechanochemically through manual grinding without adding HF as modulator and solvent with 15 h of crystallization time. The synthesized material was employed as an adsorbent for methyl orange (MO) and methyl violet (MV). The obtained material was characterized by X-ray diffraction and FTIR spectroscopy techniques. A few parameters affecting adsorption capacity were studied: including optimum pH, contact time, and initial dyes concentration. The results showed that SEM images revealed the synthesized MIL-100(Cr) has irregular polyhedron morphology, and it is thermally stable up to 375 °C based on TGA measurement. Nitrogen sorption isotherm confirmed that MIL-100(Cr) possesses high surface area and pore volume up to 1557 m2/g, and 0.76 cm3/g, respectively, and can be classified as microporous material with pore diameter of 1.82 nm. In addition, the adsorbed MO and MV were evidenced by the presence of new peaks in the FTIR spectra of MIL-100(Cr) after adsorption at 2930, 1587, 1177, 1118 cm−1 for MO adsorption and 1170, 2971 cm−1 for MV adsorption. Moreover, MIL-100 (Cr) has the maximum adsorption capacity toward MO and MV of 430.21 mg/g (MO: pH = 4, t = 60 min) and 120.48 mg/g (MV: pH = 9, t = 150 min), respectively. The MO and MV adsorption mechanism is dominated by physisorption via electrostatic interactions due to the porosity features of the adsorbent. Furthermore, it also may be followed by π–π stacking, ion-dipole interactions, and hydrogen bonds. MO and MV adsorption kinetics were described by pseudo-second-order. The nonlinearity of the intraparticle diffusion plot graph confirmed any contribution from the pore and surface of MIL-100(Cr). The MO and MV adsorption isotherm models were in good agreement with the Langmuir isotherm. [ABSTRACT FROM AUTHOR]

This study introduces a facile mechanochemical synthesis of KxMn[Fe(CN)6] (KMnHCF) and carbon nanotube (CNT) composite (KMnHCF@CNT) as a positive electrode material for potassium-ion batteries. The KMnHCF@CNT, synthesized by a simultaneous process of mechanochemical synthesis and carbon compositing, shows a homogeneous composite and achieves a much higher electron conductivity of 7.16 × 10−1 S cm−1 than the KMnHCF and CNT mixture (2.35 × 10−2 S cm−1) synthesized by the two-step process. The improved electron conductivity demonstrates reduced carbon content in the electrode and excellent rate performance of maintaining 80 mAh g−1 at 20 C in potassium cells.

Mechanochemical and solvent-based complexes of Mn(II) with cefixime and cefuroxime were synthesized and characterized by melting point and conductivity measurements, elemental analysis, FTIR spectral studies, and electronic spectral analysis. The Mn(II) complexes with cefixime and cefuroxime synthesized mechanochemically were both ash colored, while Mn(II) cefixime and cefuroxime complexes synthesized through solvent-based method were milky and ash respectively. The molar conductivity values (14.9 – 16.6 Scm2mol-1) indicate non-electrolytic nature of the complexes. The FTIR revealed that the ligands were coordinated to the Mn(II) ion through the carboxylate ions (C=O). A six coordinate octahedral geometry has been proposed for the complexes. The result of the antibacterial assay of the synthesized complexes of Mn(II) with cefuroxime generally showed better activity against Staphylococcus aureus, Streptococcus pyogenes and Methicillin-resistant Staphylococcus aureus (MRSA) than the free ligand cefuroxime. Similarly, the Mn(II) complex of cefuroxime synthesized by mechanochemical method shows higher activity against the aforementioned organisms as compared to the solution-based complex which might be as a result of solvent effect.

AbstractIntroduction: In this research, barium carbonate was synthesized via mechanochemical method from the mixture of barite concentrate-sodium carbonate. The producing of barium carbonate form barite concentrate and the evaluation of the phases/products were the goal of this research.Methods: After crushing the barite concentrate, the acid washing process was done with 1 N of HCl. The mixtures of barite concentrate-sodium carbonate with different molar ratios (BaSO4:Na2CO3=1:1, 1:2, 1:2.5) were prepared and milled in a planetary mill for different times (2 and 5 hours). The as-milled samples and the heated products were dissolved in distilled water and then the solid residues were dried in an oven. The isothermal heating of the samples was done into the alumina and zirconia crucibles. The unmilled mixture of barite concentrate-sodium carbonate was also prepared. The findings of this research were evaluated using XRF, XRD and STA methods and the microstructures of the samples were studied by SEM method.Findings: The2 and 5 h-milled mixtures showed the sign of chemical reaction between the starting materials (barite concentrate-sodium carbonate) at 720⁰C in STA results. This sign however was observed at 735 ͦC in the unmilled mixture. According to XRD patterns, the chemical reaction between barite concentrates and sodium carbonate was not completed in the milled mixtures. The signs of orthorhombic phase of barium carbonate were observed in the products after isothermal heating at700⁰C for 1 h. The results indicated that the isothermal heating of the milled mixture of barite concentrate-sodium carbonate with a molar ratio of 1:2.5 at 750⁰C for 2 h was the suitable conditions for synthesizing of barium carbonate. Additionally, the weak signs of an intermediate phase (Ca4Ba2Si6O18) were observed in the XRD patterns of the barite concentrate-sodium carbonate mixture. For comparison, the experiments were performed with pure barium sulfate sample (Barex). In the product of isothermal heating (750⁰C, 2 h) for the mixture of barium sulfate (Barex)-sodium carbonate (molar ratio :1:2.5), barium carbonate phase was produced and no trace of the intermediate phase was observed. The results of this research showed that it is possible to synthesis barium carbonate phase from the mixture of barite concentrate-sodium carbonate using ball milling process and isothermal heating.

BACKGROUND: Over the years, activated carbon has been widely used for environmental applications, including liquid or gas phase applications. However, there are many hurdles for researchers in the activated carbon field to overcome when it comes to non‐renewable materials, the utilization of individual precursors, and the complex multistep procedures of activated carbon synthesis. Therefore, in this study, the facile mechanochemical potassium carbonate (K2CO3) activation of blended precursors — palm kernel shell and petroleum coke — was investigated in terms of the activated carbon yield and carbon dioxide (CO2) adsorption capacity. RESULTS: The optimum configuration of the activated carbon production was found at temperature of 680°C, holding time of 60 min, and impregnation ratio of 1.75:1. The CO2 adsorption data at 25–120°C was best represented by the Sips model with R2 > 0.9999, where maximum CO2 adsorption capacity (qmax) was within the range of 2.24–4.32 mmol/g. The kinetic analysis was well‐represented by the pseudo‐second order model due to the high R2 and low sum of square of errors (ERRSQ) value. In terms of thermodynamic analysis, it showed that the CO2 adsorption process was physical, exothermic, and spontaneous at lower temperature. CONCLUSION: Overall, the integration of agricultural and industrial waste to value‐added activated carbon was feasible not only in reducing waste disposal problems but also in facilitating CO2 mitigation. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Different from conventional single-network hydrogels, double-network (DN) hydrogels have attracted great research interest due to their ultra-high toughness; however, the working principles behind their complex mechanochemical coupling have not been fully understood. In this study, an extended potential well model is formulated to investigate the host-guest chemistry and the free-energy trap effect, coupled in DN hydrogels undergoing mechanochemical toughening. According to the Morse potential and mean field model, the newly established potential well model can describe the coupled binding of the host brittle network and guest ductile network in the DN hydrogels. A free-energy equation is further proposed to describe the working principles of the mechanochemical coupling and toughening mechanisms using the depth, width, and trap number of potential wells, which determine the barrier energy of the host brittle network, the mesh size of guest ductile network, and the mechanochemical host-guest interactions of these two networks, respectively. Finally, the effectiveness of the proposed model is verified using finite-element analysis (FEA) and experimental results of various DN hydrogels reported in the literature. Using the potential well model, which has host-guest chemistry from both brittle and ductile networks, this study clarifies the linking of mechanochemical coupling and toughening mechanisms in DN hyrdogels. [ABSTRACT FROM AUTHOR]

(1) Dental caries, periodontitis, or peri-implantitis are commensal infections related to oral biofilm former bacteria. Likewise, magnesium oxide nanoparticles (MgO-NPs) were studied to introduce them to the antibacterial properties of a few microorganisms. Considering this, the purpose of the present investigation was to determine the antibacterial properties of MgO-NPs on representative oral strains. (2) Methods: MgO-NPs with a cubic crystal structure were obtained by magnesium hydroxide mechanical activation. After synthesis, the MgO-NPs product was annealed at 800 °C (2 h). The MgO-NPs obtained were tested against ten oral ATCC strains at ten serial concentrations (1:1 20.0–0.039 mg/mL per triplicate) using the micro-broth dilution method to determine the minimal inhibitory concentration (MIC) or minimal bactericidal concentration (MIB). Measures of OD595 were compared against each positive control with a Student's t-test. Viability was corroborated by colony-forming units. (3) Results: The polycrystalline structure had an average size of 21 nm as determined by X-ray diffraction and transmission electron microscopy (high resolution). Antimicrobial sensitivity was observed in Capnocytophaga gingivalis (MIB/MIC 10–5 mg/mL), Eikenella corrodens (MIB 10 mg/mL), and Streptococcus sanguinis (MIB 20 mg/mL) at high concentrations of the MgO-NPs and at lower concentrations of the MgO-NPs in Actinomyces israelii (MIB 0.039 mg/mL), Fusobacterium nucleatum subsp. nucleatum (MIB/MIC 5–2.5 mg/mL), Porphyromonas gingivalis (MIB 20 mg/mL/MIC 2.5 mg/mL), Prevotella intermedia (MIB 0.625 mg/mL), Staphylococcus aureus (MIC 2.5 mg/mL), Streptococcus mutans (MIB 20 mg/mL/MIC 0.321 mg/mL), and Streptococcus sobrinus (MIB/MIC 5–2.5 mg/mL). (4) Conclusions: The MgO-NPs' reported antibacterial properties in all oral biofilm strains were evaluated for potential use in dental applications. [ABSTRACT FROM AUTHOR]

A tremendous amount of ammonia (NH 3) has been produced by the Haber-Bosch method during the last 100 years. However, it is imperative to develop a new alternative to produce NH 3 in a more environmentally friendly way due to the high energy cost and the large amount of greenhouse gas emissions in the Haber-Bosch method. Although the mechanochemical process has been regarded as an emerging technique, the understanding at the atomic level is limited. Here, we computationally model the mechanochemical ball-milling method by molecular dynamics simulations with the reactive force field (ReaxFF) developed in this work. We find that strain applied to Fe surfaces significantly enhances the N 2 dissociation as well as the NH x (x = 1–3) formation on Fe(110), whereas the strain effect is negligible on Fe(111). From the von Mises stress analyses, the applied strain (mechanical) energies transfer the Fe catalysts and N atoms adsorbed on Fe surfaces and then activate NH x formation. Moreover, mechanical strain boosts a new mechanism for NH formation, the rate-determining step, via the direct interaction between the dissociated N atom on the Fe surface and the H 2 molecule, which is supported by density functional theory calculations. This study shows that the mechanochemical process is readily operated on Fe catalysts and promising for NH 3 synthesis. [Display omitted] • Mechanochemical NH 3 synthesis using ball-milling method is modeled by reactive molecular dynamics. • Strain applied to Fe(110) significantly enhances the N 2 dissociation as well as the NH x (x = 1–3) formation. • From the von Mises stress analyses, applied strain transfers energy to Fe and ∗N and then activates NH 3 formation. • New NH formation mechanism is proposed as a dominant process by DFT calculations. [ABSTRACT FROM AUTHOR]

Pulverized rock samples are widely used in laboratory experiments, e.g., to assess microbial or abiotic processes in batch incubation tests. However, it is unclear if ball-milled samples accurately reflect in-situ conditions and if observed processes are affected by by-products artificially generated during the sample preparation procedure. As such, this study examined the effects of dry ball milling on the release of gases, which include C 1 –C 4 hydrocarbons, carbon dioxide (CO 2), hydrogen (H 2), and low molecular weight organic acids (LMWOAs) from different sedimentary rocks. The experiments involved pulverization using a gas-tight zirconium oxide planetary ball mill followed by wet and dry batch incubation and thermal desorption up to 200 °C. During milling, all sedimentary rocks, except a low organic carbon sandstone, yielded methane (CH 4), ethane (C 2 H 6), propane (C 3 H 8), butane (C 4 H 10), H 2 , CO 2 , and unsaturated hydrocarbons, e.g., ethene (C 2 H 4). Sandstones only yielded H 2 , CH 4, and CO 2. Stable carbon isotope signatures of these products are similar to thermogenic gases. The gases were also detected in subsequent wet incubation experiments (after gases from milling had been removed). Additionally, formate, acetate, and citrate, were detected in all samples except for sandstone. Pyruvate, malate, and succinate were also detected in some samples. Thermal desorption products of powdered limestone, shale, and pyrite concretion samples included organic acids, such as acetate and formate, which were found at higher levels in milled samples than in crushed particles (1 mm). The original geological thermal maturity of the studied sedimentary rock samples was low (below "oil window") and, thus, considerably below "gas window," suggesting that most of the detected gases were generated during ball milling. H 2 generated during ball milling may be derived from the reduction of water from fluid inclusion or phyllosilicates, involving the formation of reactive mineral surfaces or radicals. Notably, the concentrations of gaseous hydrocarbons derived from milling are relatively high and comparable to "wet" gases. At the same time, these data indicate that substantial amounts of gases and LWMOAs might be artificially generated during laboratory batch experiments with milled samples. Hence, ball milled rock samples must be used with caution if assessing (bio-)geochemical processes for natural environments. • Ball milling of low maturity sediments release C 1 –C 4 hydrocarbons, H 2 and CO 2. • Stable carbon isotope data show that mechanically generated hydrocarbons have a thermogenic signature. • Generation of H 2 is likely due to freshly broken mineral surfaces or from phyllosilicates. • Ball milled sediments have great potential to release organic acids. • Ball milled sediments could impact interpretation of biogeochemical experiments. [ABSTRACT FROM AUTHOR]

Large amounts of hazardous fluorine-containing solid waste (HFSW) are produced globally each year. Recycling HFSW not only conserves valuable F resources but also serves as a crucial step towards environmental sustainability. This work proposed an efficient and green approach for F removal and recovery from the HFSW using a mechanochemical method. The results showed that MgF 2 component in the HFSW can be almost completely converted to NaF and Mg(OH) 2 by the mechanochemical force with NaOH as co-grinding agent. A possible NaOH mechanochemical decomposition and conversion mechanism of MgF 2 is also proposed based on thermodynamics, XRD, TEM and DFT calculations. By optimizing the mechanochemical conditions, such as NaOH concentration of 35 mol/L, ball-to-material ratio of 10:1 g/g, liquid-solid-ratio of 1.8 mL/g, mechanical activation speed of 600 rpm, and mechanical activation time of 150 min, 99.51 % of F in the HFSW can be leached. Finally, 98.69 % purity of NaF product was recovered from the as-obtained F-containing leachate through N 235 extraction and evaporative crystallization. The results of this work are expected to provide a promising solution for F removal and recovery from HFSW. [Display omitted] • NaOH was selected as the co-grinding reagent for mechanochemical. • Over 99 % of F removal from hazardous fluorine-containing solid waste. • The mechanochemical conditions were optimized with the response surface analysis. • Possible mechanochemical conversion mechanism of fluorinated components is proposed. [ABSTRACT FROM AUTHOR]

The relative slow carbonation efficiency for conventional wet and dry carbonation of recycled concrete fines (RCF) limits its resource industrial utilization. In this study, an innovative mechanochemical carbonation (MC) method was developed. The carbonation kinetics, phase assemblage and microstructure evolution of RCF during the MC process were extensively examined. The results exhibited a substantial enhancement in the carbonation efficiency and CO 2 utilization rate, as evidenced by achieving a notable carbonation degree within 10 min. This accomplishment surpassed what could be achieved even after a prolonged 2 h period of wet carbonation, and the CO 2 uptake capacity and utilization rate achieved via MC reached >0.3 g-CO 2 /g-RCF and 80 %, respectively. The superior performance of MC was ascribed to the influence of mechanochemical effects. These effects contributed to the refinement in the geometrical characteristics of RCF, exfoliation of the passivating layers, and facilitation of CO 2 dissolution, which favored the structural disintegration of RCF and carbonation progress. Another distinctive aspect of MC treatment was the production of a greater proportion of metastable CC characterized by reduced crystalline size, which was attributed to modifications in the carbonation environment and the structural alterations induced by mechanochemical effects. Moreover, the precipitation of silica gels commenced at approximately 4 min in the MC process, a notably earlier onset when compared with wet carbonation; additionally, a greater abundance of silica gels was observed in the current MC procedure, resulting from the higher carbonation degree caused by mechanochemical effects. The encouraging conclusions in the present work validated the feasibility of producing carbonated RCF more efficiently and paved the way for future industrial practice. [ABSTRACT FROM AUTHOR]

Recently, several methods has been used for the synthesis of bimetal oxide nanocomposite, however, very few studies are available on the solvent free mechanochemical synthesis of nanomaterials. In this study, mortar and pestle assisted fabrication of copper oxide-zirconium dioxide nanocomposite (CuO–ZrO _2 NC) was carried out and was calcined at 300, 600 and 900 °C. The variation in crystallographic parameters was examined through x-ray diffraction (XRD) and the crystallite size was found to be gradually increased with increasing calcination temperature. The morphological changes with increasing calcination temperature were traced during scanning electron microscopy (SEM) analysis. The percentage elemental composition was verified through energy dispersive x-ray (EDX) spectroscopy whereas the functional group analysis was done through Fourier transform infrared (FTIR) spectroscopy, where the intensity of peaks assigned to hydroxyl moiety decreased with increasing calcination temperature. The CuO–ZrO _2 NCs were used as a photocatalysts for the degradation of the Fluorescein in the presence of solar light and highest photodegradation (77.27%) was noticed for the CuO–ZrO _2 NC calcined at 900 °C.

Energy storage systems (ESSs) are attracting increasing attention for the development of sustainable and renewable energy technologies owing to limited fossil fuels. Supercapacitors are gaining significant interest as energy storage devices owing to their high-power density and long-term cycle stability. The use of suitable electrode materials affects the performance of supercapacitors. In this study, we fabricated a carboxyl-doped graphene nanoplatelet (CGnP) via a mechanochemical reaction. Additionally, CGnP was activated by controlling parameters such as temperature, flow rate, and maintenance period and evaluated as an electrode material for supercapacitors. The effect of the specific surface area (SSA) and functional groups of the fabricated samples on the capacitance was confirmed by controlling the activation parameters. The activated CGnP with 300 mL/min of CO2 at 1173 K for 4 h exhibited a high SSA of 1300 m2/g. The activated CGnP (180 F/g), with a high SSA, showed an increased capacitance of 46% compared to pristine CGnP (123 F/g). Additionally, activated CGnP1100 demonstrated good wettability and exhibited excellent stability with a low capacitance decrease of 6.1%, even after 10,000 cycles.