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This study introduces a novel method for hydrogen fuel generation using ultrasound technology through the disassociation of water into hydrogen and oxygen. The proposed experimental setup comprises several key components: a power supply, an ultrasonic generator, two transducers, a reactor vessel, two vapor traps, a condenser, a valve, a hydrogen storage, a humidity sensor and a hydrogen measurement sensor. The system operates at a power of 100 W and a frequency of 40 kHz, and the reactor vessel contains 2L of solution. The study results show a variability in hydrogen production rates under different experimental conditions. The distilled water used in the experiments at 25 °C produces hydrogen at a rate of 0.05 μmol/min, which increases to 0.066 μmol/min at 70 °C. The tap water gives hydrogen production rates ranging from 0.044 μmol/min at 25 °C to 0.06 μmol/min at 70 °C. The lake water produces hydrogen at rates between 0.036 μmol/min and 0.054 μmol/min, while the wastewater ranges from 0.028 μmol/min to 0.044 μmol/min. The present study investigates the effect of CO 2 injection into the sonoreactor on the system performance and shows that hydrogen production rates increase over a 20-min period for the water resources, with higher CO 2 flow rates leading to improved production rates. These findings demonstrate the potential of ultrasound technology for eco-friendly hydrogen production, marking a promising alternative to conventional methods and contributing valuable insights to the field of sustainable energy. [Display omitted] • The study investigates an innovative sonic method of hydrogen generation. • The present system is proposed for clean hydrogen generation. • The experiments are conducted at a frequency of 40 kHz and power of 100 ± 10 W. • The hydrogen generation is tested under various water sources at different temperatures. • The hydrogen generation is assessed by injecting CO 2 into the sonoreactor solution. [ABSTRACT FROM AUTHOR]

Cerium oxide (CeO2), one of the most significant heterogeneous catalysts, has attracted extensive research interest. Herein, ultrafine spherical CeO2 with a diameter of 5 nm is successfully synthesized within a reaction time of 25 min by a simple and environmentally friendly sonochemical method without any additional oxidants or high temperature and pressure conditions, and 50 nm spherical CeO2 was obtained by heat treating the 5 nm spherical CeO2 in 400°C air atmosphere condition for 3 h. By controlling the ultrasonic condition, a specific surface area of up to 194.2 m2/g and a bandgap as low as 2.2 eV are achieved in the CeO2 nanoparticles without any heat treatment. Further study has shown that the as‐prepared spherical CeO2 without heat treatment exhibits remarkable photocatalytic and antibacterial activities under visible light conditions. The study is beneficial for energy conservation in fabricating ultrafine photocatalytic and antibacterial nanomaterials. [ABSTRACT FROM AUTHOR]

Sonochemistry is a fascinating field that has drawn considerable interest from researchers across different disciplines. One of the key challenges in this field is the accurate characterization of the sonochemical field, which is crucial for understanding the underlying mechanisms and optimizing the process. To address this challenge, researchers have developed various monitoring methods that allow them to measure key parameters such as the intensity, frequency, and distribution of acoustic waves in the sonoreactor. In this review, we focus on the chemical dosimetry techniques that are commonly used for sonochemical monitoring. These techniques have been extensively studied in the literature and are known for their reliability and accuracy. However, as we will see, the performance of these techniques can vary depending on the chemical nature of the probing species and the experimental conditions, highlighting the need for a careful selection and calibration of the monitoring method. We begin by discussing the principles of chemical dosimetry in sonochemistry and how these methods can be used to measure key sono‐acoustic parameters. We then provide a detailed analysis of the various dosimetry techniques, including their advantages, limitations, and applicability under different operating conditions. In summary, our review serves as a valuable resource for researchers seeking to optimize their sonochemical experiments and contribute to the advancement of this fascinating field. [ABSTRACT FROM AUTHOR]

Nanoparticles exhibit distinct physical and chemical characteristics and are becoming increasingly significant in the production of innovative nanodevices for many applications in physics, biology, biomedicine, and pharmaceuticals. The aim of this research work is to synthesize Fe (II) and Cu (II) nano-sized complexes of trimethoprim (TMP) using the sonication method, characterize them using physical and spectroscopic methods, and carry out ADMET studies on the synthesized complexes. The spectroscopic and physical studies showed a change in colour and an increase in melting point due to coordination. The novel compounds were slightly soluble in water. The XRD tests revealed that the new nanocomplexes were crystalline. The Fe (II) nanocomplexes had a size of 57.56 nm and the Cu (II) nanocomplexes had a size of 69.88 nm. These values were found using Debye-Scherrer’s equation. The FTIR results of the TMP, Fe (II), and Cu (II) nanometal complexes showed a shift of the amino group band from 3317 to 3295 and 3202 cm−1 and the azomethine band from 1633 to 1625 and 1592 cm−1 in the complexes. In the complexes, the proton NMR spectra revealed an upfield shift of the amine proton. The carbon-13 NMR spectra showed that CH2 was involved in coordination with the metal ions. The spectra studies indicated that TMP coordinated with the metal ions through the methylene and amino groups. A trigonal bipyramid structure was proposed for the complexes. The results of the Rule of 5 studies indicated that the test compounds had a good drug-likeness prediction, with only one violation. The ADMET prediction showed that all of the compounds demonstrated improved pharmacokinetic characteristics and adhered to the RO5 requirement. These findings highlight the therapeutic potential of Fe (II) and Cu (II) nano-sized TMP complexes as bioactive compounds that warrant further investigation for pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Nanoparticle drug delivery systems are precisely designed technologies that utilize nanoparticles to deliver therapeutic drugs to specific targets and regulate their release. In recent times, nanoparticles have garnered significant interest owing to their potential for efficient drug delivery. This work is aimed at synthesizing Fe(II) and Cu(II) nano-sized complexes of sulfamethoxazole (SMX) using the sonication method. The physical and spectroscopic studies showed a colour change from white to grey, and a decrease in melting points suggested the formation of the metal complexes. The nanometal complexes were insoluble in water. XRD analysis showed that the crystallite sizes of Fe(II) and Cu(II) nanometal complexes were determined to be 76.08 nm and 37.13 nm, respectively, using the Debye-Scherrer equation. The FTIR results of the SMX, Fe(II), and Cu(II) nanometal complexes showed a shift of the amine band from 3243 to 3191 cm−1 and the sulfone band from 1154 to 1092 cm−1 in both complexes. The proton NMR showed a shift of the amine proton from 6.100 ppm to 6.035 ppm in the spectra of the Cu(II) complex. The amine chemical shift was absent in the spectra of the Fe(II) complex, showing deprotonation. The carbon-13 NMR spectra showed a similar chemical shift. The spectra studies indicated that SMX coordinated with the metal ions through the amino and sulfone groups. A tetrahedral structure was proposed for the complexes. SMX coordinated as a bidentate ligand to Fe(II) and Cu(II) ions. [ABSTRACT FROM AUTHOR]

This research investigated the performance of bentonite and Al-PILC as catalysts in ethanol conversion to diethyl ether through a dehydration reaction. The natural bentonite was intercalated with the pillaring agent Keggin-ion Al13 to obtain Al-intercalated bentonite. Al-intercalated bentonite has been synthesized using conventional stirring and ultrasonication. Al-intercalated bentonite was calcined at 400 °C for 4 h to produce Al2O3 pillared bentonite (Al-PILC). The dehydration reaction was conducted using a 0.2 g catalyst and 10 mL of ethanol with a nitrogen gas flow rate of 20 mL/min at various reaction temperatures (200, 225, and 250 °C) using a fixed bed microreactor. The characterization results reveal that Al-PILC synthesized by sonochemistry exhibits significantly higher surface area and total acidity values than bentonite and Al-PILC synthesized by conventional methods because of the formation of stable Al2O3 pillars in the interlayer spaces of bentonite. The sonochemically synthesized Al-PILC produces optimum ethanol conversion and diethyl ether yield of 46.05% and 41.11%, respectively. The conversion of ethanol and diethyl ether yield reaches an optimum result at 225 °C. Based on this study, the pillarization of bentonite using Al2O3 can enhance its catalytic properties toward diethyl ether production. [ABSTRACT FROM AUTHOR]

Mechanochemistry constitutes a burgeoning field that investigates the chemical and physicochemical alterations of substances under mechanical force. It enables the synthesis of materials which is challenging to obtain via thermal, optical or electrical activation methods. In addition, it diminishes reliance on organic solvents and provides a novel route for green chemistry. Today, as a distinct branch alongside electrochemistry, photochemistry, and thermochemistry, mechanochemistry has emerged as a frontier research domain within chemistry and material science. In recent years, the intersection of mechanochemistry with controlled radical polymerization has witnessed rapid advancements, providing new routes to polymer science. Significantly, we have experienced breakthroughs in methods relying on sonochemistry, piezoelectricity and contact electrification. These methodologies not only facilitate the synthesis of polymers with high molecular weight but also enable precise control over polymer chain length and structure. Transitioning from harsh to mild conditions in mechanochemical routes has facilitated a significant improvement in the controllability of mechanochemical polymerization. From this perspective, we introduce the progress of mechanochemistry in controlled radical polymerization in recent years, aim to clarify the historcial development of this topic. [ABSTRACT FROM AUTHOR]

There is a growing interest in using green technologies in the food industry. As a green processing technique, ultrasound has a great potential to be applied in many food applications. In this review, the basic mechanism of ultrasound processing technology has been discussed. Then, ultrasound technology was reviewed from the application of assisted food processing methods, such as assisted gelation, assisted freezing and thawing, assisted crystallization, and other assisted applications. Moreover, ultrasound was reviewed from the aspect of structure and property modification technology, such as modification of polysaccharides and fats. Furthermore, ultrasound was reviewed to facilitate beneficial food reactions, such as glycosylation, enzymatic cross-linking, protein hydrolyzation, fermentation, and marination. After that, ultrasound applications in the food safety sector were reviewed from the aspect of the inactivation of microbes, degradation of pesticides, and toxins, as well inactivation of some enzymes. Finally, the applications of ultrasound technology in food waste disposal and environmental protection were reviewed. Thus, some sonoprocessing technologies can be recommended for the use in the food industry on a large scale. However, there is still a need for funding research and development projects to develop more efficient ultrasound devices. [ABSTRACT FROM AUTHOR]

Plastics have become indispensable in modern society; however, the proliferation of their waste has become a problem that can no longer be ignored as most plastics are not biodegradable. Depolymerization/degradation through sustainable processes in the context of the circular economy are urgent issues. The presence of multiple types of plastic materials makes it necessary to study the specific characteristics of each material. This mini-review aims to provide an overview of technological approaches and their performance for the depolymerization and/or degradation of one of the most widespread plastic materials, polypropylene (PP). The state of the art is presented, describing the most relevant technologies focusing on advanced oxidation technologies (AOT) and the results obtained so far for some of the approaches, such as ozonation, sonochemistry, or photocatalysis, with the final aim of making more sustainable the PP depolymerization/degradation process. [ABSTRACT FROM AUTHOR]

Sonochemistry is the use of ultrasonic waves in an aqueous medium, to generate acoustic cavitation. In this context, sonochemistry emerged as a focal point over the past few decades, starting as a manageable process such as a cleaning technique. Now, it is found in a wide range of applications across various chemical, physical, and biological processes, creating opportunities for analysis between these processes. Sonochemistry is a powerful and eco‐friendly technique often called "green chemistry" for less energy use, toxic reagents, and residues generation. It is increasing the number of applications achieved through the ultrasonic irradiation (USI) method. Sonochemistry has been established as a sustainable and cost‐effective alternative compared to traditional industrial methods. It promotes scientific and social well‐being, offering non‐destructive advantages, including rapid processes, improved process efficiency, enhanced product quality, and, in some cases, the retention of key product characteristics. This versatile technology has significantly contributed to the food industry, materials technology, environmental remediation, and biological research. This review is created with enthusiasm and focus on shedding light on the manifold applications of sonochemistry. It delves into this technique's evolution and current applications in cleaning, environmental remediation, microfluidic, biological, and medical fields. The purpose is to show the physicochemical effects and characteristics of acoustic cavitation in different processes across various fields and to demonstrate the extending application reach of sonochemistry. Also to provide insights into the prospects of this versatile technique and demonstrating that sonochemistry is an adapting system able to generate more efficient products or processes. [ABSTRACT FROM AUTHOR]

Jet pump cavitation reactors (JPCRs) have significant potential to be used in water treatment applications. During their operation, the hydroxyl radicals generated by cavitation collapse produce a strong oxidation capacity, which is one of the key mechanisms in disrupting algal cells. In this paper, we investigate the hydroxyl radicals produced by single cavitation bubble in a JPCR. The numerical method includes a bubble dynamic model, molecular diffusion model, energy balance equation, and chemical reaction model for predicting the hydroxyl radical production. Additionally, the pressure distribution within a JPCR is tested and used to analyze the single-bubble performance. The effects of the JPCR operating conditions and structure parameters on hydroxyl radical production are further discussed. Our results indicate that, when the flow rate ratio is positive, the number of hydroxyl radicals is closely related to the development and collapse of the cavitation bubble and reaches a peak value under the critical condition. When the flow rate ratio is negative, the maximum production of hydroxyl radicals appears under backflow stagnation condition. In general, increasing the throat length–diameter ratio and diffuser angle encourages the production of hydroxyl radicals, whereas increasing the area ratio inhibits their generation. [ABSTRACT FROM AUTHOR]

At least 16 bulk polymorphs of linked icosahedrons exist in boron that are not found in other materials, due to the low covalent radius and sp² hybridization capacity of boron atoms. One of them is borophene, an exciting new nanomaterial with a wide range of possible energy uses. The existence of borophene, a two-dimensional (2D) material, has been proven by both theoretical and experimental studies. Borophene's high magnetic conductivity, theoretical specific capacities, and ion transport properties make it a promising candidate in energy applications (EAs). In this study, firstly, the structure, chemical, and physical properties of borophene were mentioned. Then, in terms of synthesis approaches, both top-down and bottom-up techniques such as ultrahigh vacuum (UHV), chemical vapor deposition (CVD), exfoliation by sonochemistry (ExS), molecular beam epitaxy (MBE) and multi-step thermal decomposition (MTD) were discussed. Finally, its use as a catalyst in high-metal-ion batteries, hydrogen storage (HS), nanoelectronics applications hydrogen evolution reaction (HER) was mentioned. [ABSTRACT FROM AUTHOR]

This research aims to present a sonochemical synthesis method for high-purity willemite nanopowders. Initially, zinc silicate hydrate nanoparticles were created using a modified sonochemistry method in which zinc salts and waterglass were used as starting materials to obtain zinc silicate precipitate under pH-controlled conditions (11–11.5) and Argon gas flux. Following that, the precipitate was heat treated at various temperatures. TGA/DSC, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dispersive X-ray spectrometry (EDX), and N2 gas adsorption characterizations were also used to assess phase changes, morphological properties, microstructures, and chemical composition. The formation temperature of a well-crystalline willemite monophase was determined to be 890 °C, and this was supported by XRD analysis. The synthetized material had high homogeneity and excellent purity, according to EDX elemental mapping. Its nanometric nature was further confirmed by microscopic observations (SEM, TEM). Notably, compared to previously reported methods, the aforementioned technique uses a moderate synthesizing temperature, making it economical for mass production and potentially useful in a variety of industrial fields, including ceramics, paints, plastics, biomaterials, and composites, among others. EDX elemental mapping demonstrated high homogeneity and excellent purity of the material. Microscopic observations (SEM, TEM) further confirmed its nanometric character. Notably, the aforementioned method employs a moderate synthesizing temperature compared to previously reported methods, making it cost-effective for mass production with potential applications in various industrial fields, such as ceramics, paints, plastics, biomaterials, and composites, among others. [ABSTRACT FROM AUTHOR]

Cellulose is used widely in antimicrobial packaging due to its abundance in nature, biodegradability, renewability, non-toxicity, and low cost. However, how efficiently and rapidly it imparts high antimicrobial activity to cellulose-based packaging materials remains a challenge. In this work, Ag NPs were deposited on the surface of carboxymethyl cellulose/starch/N'N Methylenebisacrylamide film using ultrasonic radiation. Morphology and structure analysis of as-prepared films were conducted, and the antibacterial effects under different ultrasonic times and reductant contents were investigated. These results showed that Ag NPs were distributed uniformly on the film surface under an ultrasonic time of 45 min. The size of Ag NPs changes as the reducing agent content decreases. The composite film demonstrated a slightly better antibacterial effect against E. coli than against S. aureus. Therefore, this work can provide valuable insights for the research on antimicrobial packaging. [ABSTRACT FROM AUTHOR]

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Ultrasonic baths and sonochemical reactors are widely used in industrial applications dealing with surface cleaning and chemical synthesis. The processes of erosion, cleaning and structuring of the surface can be typically controlled by changing relevant influential parameters. In particular, in this work, we experimentally investigate the effect of NaCl concentration (0-5.5 mol/L) on the erosion of an aluminum foil under ultrasonic exposure at a frequency of 28 kHz. Special attention is paid to the determination of cavitation zones and their visualization using heat maps. It is found that at low NaCl concentration (0.3 mol/L), the foil destruction rate is higher than in distilled water. At higher concentrations of salt, cavitation takes place mainly in the upper part of the container. [ABSTRACT FROM AUTHOR]

Herein a novel gum acacia‐alginate nanogel (GAA) was synthesized via ultrasound‐assisted crosslinking by DPPH and applied for the removal of coomassie brilliant blue (CBB) dye. The fabrication of GAA and its interaction with CBB was specified via FTIR, XRD, SEM, and TEM techniques. The process parameters at which maximum adsorption efficiency, qe (80.12 mg/g), and % efficiency >94 % were achieved include dosage (0.8 g/L), time (80 min), initial dye concentration (20 mg/L), and pH (6). Ultrasound‐assisted uptake was greater than stirring‐assisted due to acoustic cavitation′s hydrodynamic and thermal processes. Pseudo‐second‐order model described the adsorption kinetics and the diffusion mechanism suggested that the rate‐determining step was controlled by both the intraparticle diffusion and the liquid film models. Isotherms showed an excellent fit to the Freundlich model based on higher R2 (0.998) and lower standard error of estimate values (SEE=0.367). The −ΔG° values (−8.152, −8.292, −8.433, −8.586 kJ/mol) indicated that the adsorption process was feasible and spontaneous. The removal of CBB ensued via hydrogen bonding, electrostatic, π‐π, and n‐π interactions. The maximum adsorption capacity of 182.096 mg/g, eco‐friendly characteristics along with regeneration competence depicted that GAA could be effective for scavenging CBB from wastewater. [ABSTRACT FROM AUTHOR]

This comprehensive review delves into the utilization of ultrasound for hydrogen generation, emphasizing the key mechanisms and techniques involved. One of the focal points of the study is the exploration of the generation and detection of cavitation bubbles, which are induced by ultrasound waves. An in-depth overview of various experimental setups that employ ultrasound technology for hydrogen production is also provided. A comparative analysis of these setups reveals differences in crucial parameters such as acoustic intensity, liquid temperature, and frequency. These are the key parameters identified as significant determinants affecting the hydrogen yield and efficiency. This review paper also highlights the potential applications of sonohydrogen as a viable energy resource. While challenges such as the high costs of ultrasound equipment and the need for efficient catalysts exist, the inherent benefits make sonohydrogen a compelling subject for future research and development. The study shows that there is no one-size-fits-all approach, accentuating the importance of understanding these parameters for optimizing the process of hydrogen production. Although the technology is primarily in the experimental phase, existing research indicates that the sonohydrogen production holds considerable potential for large-scale applications. [Display omitted] • The study explores ultrasound's role in enhancing hydrogen production. • The article reviews various experimental setups and comparing them. • The manuscript identifies key parameters affecting sonohydrogen production. • The study discusses the potential dimensions of sonohydrogen options and future research directions. • It examines scaling sonohydrogen production challenges for industrial use. [ABSTRACT FROM AUTHOR]

Hydrodynamic cavitation (HC) has emerged as a promising technology for water disinfection. Interestingly, when subjected to specific cavitation pressures, jet pump cavitation reactors (JPCRs) exhibit effective water treatment capabilities. This study investigated the cavitation flow and vorticty transport in a JPCR with various area ratios by utilizing computational fluid dynamics. The results reveal that cavitation is more likely to occur within the JPCR as the area ratio becomes smaller. While as the area ratio decreases, the limit flow ratio also decreases, leading to a reduced operational range for the JPCR. During the cavitation inception stage, only a few bubbles with limited travel distances are generated at the throat inlet. A stable cavitation layer developed between the throat and downstream wall during the limited cavitation stage. In this phase, the primary flow carried the bubbles towards the outlet. In addition, it was found that the vortex stretching, compression expansion, and baroclinic torque terms primarily influence the vorticity transport equation in this context. This work may provide a reference value to the design of JPCRs for water treatment.

1,3,5-triazine derivatives are useful compounds with potential applications in various branches of chemical industry, including pharmaceutical chemistry, cosmetic chemistry, photochemistry, and organic chemistry. Due to the growing environmental requirements on conducting efficient, economical, and safe syntheses, development of new methods for synthesizing organic compounds is highly desirable. In this publication, we present a protocol for the synthesis of 1,3,5-triazine derivatives using a sonochemical approach. In as little as 5 min, it is possible to obtain most of the investigated compounds with a yield of over 75%. An undeniable advantage of this method, besides its short time, is the use of water as the solvent. Furthermore, we provide examples that the sonochemical method may be more versatile than the competing microwave method. Analysis conducted using the DOZNTM 2.0 tool revealed that in terms of the 12 principles of green chemistry, the developed sonochemical method is 13 times “greener” than the classical one. Additionally, it has been demonstrated that the investigated molecules are attractive for their application as drug-like compounds.

Sonochemistry contributes to green science as it uses less hazardous solvents and methods to carry out a reaction. In this review, different reactor designs are discussed in detail providing the necessary knowledge for implementing various processes. The main characteristics of ultrasonic batch systems are their low cost and enhanced mixing; however, they still have immense drawbacks such as their scalability. Continuous flow reactors offer enhanced production yields as the limited cognition which governs the design of these sonoreactors, renders them unusable in industry. In addition, microstructured sonoreactors show improved heat and mass transfer phenomena due to their small size but suffer though from clogging. The optimisation of various conditions of regulations, such as temperature, frequency of ultrasound, intensity of irradiation, sonication time, pressure amplitude and reactor design, it is also discussed to maximise the production rates and yields of reactions taking place in sonoreactors. The optimisation of operating parameters and the selection of the reactor system must be considered to each application’s requirements. A plethora of different applications that ultrasound waves can be implemented are in the biochemical and petrochemical engineering, the chemical synthesis of materials, the crystallisation of organic and inorganic substances, the wastewater treatment, the extraction processes and in medicine. Sonochemistry must overcome challenges that consider the scalability of processes and its embodiment into commercial applications, through extensive studies for understanding the designs and the development of computational tools to implement timesaving and efficient theoretical studies.

Traditional methods for algae removal in drinking water treatment, such as coagulation and sedimentation, face challenges due to the negative charge on algae cells’ surfaces, resulting in ineffective removal. Ultrasonic cavitation has shown promise in enhancing coagulation performance by disrupting extracellular polymer structures and improving cyanobacteria removal through various mechanisms like shear force and free radical reactions. However, the short lifespan and limited mass transfer distance of free radicals in conventional ultrasonic treatment lead to high energy consumption, limiting widespread application. To overcome these limitations and enhance energy efficiency, advanced carbon-based materials were developed and tested. Nitrogen-doped functional groups on nanodiamond surfaces were found to boost sonosensitivity by increasing the production of reactive oxygen species at the sonosensitizer-water interface. Utilizing low-power ultrasound (0.12 W/mL) in combination with N-ND treatment for 5 min, removal rates of Microcystis aeruginosa cells in water exceeded 90 %, with enhanced removal of algal organic matters and microcystins in water. Visualization through confocal microscopy highlighted the role of positively charged nitrogen-doped nanodiamonds in aggregating algae cells. The synergy between cell capturing and catalysis of N-ND indicates that efficient mass transfer of free radicals from the sonosensitizer’s surface to the microalgae’s surface is critical for promoting cyanobacteria floc formation. This study underscores the potential of employing a low-intensity ultrasound and N-ND system in effectively improving algae removal in water treatment processes.

Sonochemistry under controlled conditions has proven effective in medicinal chemistry and drug development. It can substantially shorten reaction timelines from days or hours to minutes. A convenient one-pot synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazole derivatives catalyzed by PTSA and benzenesulfonic acid in ethanol as solvent, under ultrasonic irradiation and without ultrasound irradiation at 50° C has been achieved successfully. These 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazole derivatives synthesis were also accomplished using different solvents viz., Methanol, Ethanol, DCM, DMF, Acetonitrile and THF and PTSA as the catalyst. This method yielded the highest % synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazole derivatives with PTSA as the catalyst in solvent ethanol. These reactions were also optimized for % of PTSA catalyst required to obtain the maximum yield of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazole derivatives with and without ultrasound irradiation at 50° C. Synthesis of 2,4,5-trisubstituted Imidazole derivatives reaction follows first-order rate kinetics while that of 1,2,4,5-tetrasubstituted Imidazole derivatives reaction follows the second-order rate kinetics. Furthermore, sonochemistry has higher yields, lower cost, easier workups, and higher purity than conventional thermal organic synthesis, which has lower yields, tedious workups, longer reaction periods, lower purity, and numerous byproducts. [ABSTRACT FROM AUTHOR]

Metal-free hydride stabilized boron nanosheets (H-BNS) were prepared in an aqueous medium without using noble metal growth substrates via sonochemistry. The reducing ability of H-BNS was demonstrated with Au3+(aq) reduction, and its layered morphology is exploited for Li-ion battery (LIB) applications. [ABSTRACT FROM AUTHOR]

This editorial discusses the common aspects and challenges of photocatalysis and sonocatalysis for the degradation of organic pollutants in aqueous solutions. While these techniques are sometimes seen as competitors, their fundamental mechanisms for pollutant degradation are different. Photocatalysis involves the photoexcitation of semiconducting particles, while sonocatalysis involves the simultaneous action of heterogeneous catalysts and sonochemistry. The editorial highlights the major trends in both photocatalysis and sonocatalysis for environmental applications, including the development of photocatalyst morphology, the utilization of thermal effects, and the combination of sonochemistry with other methods. The editorial concludes that sonophotocatalysis shows promise for environmental applications but faces technical challenges for large-scale implementation. [Extracted from the article]

The promising application of mechanochemical (MC) and sonochemical (SC) synthesis methods for the obtaining of nano-dispersed oxide materials with a perovskite structure (BaTiO3, CaTiO3, and LiNbO3) and higher specific surface value as compared to samples obtained by traditional methods is shown. Synthesized samples exhibit high photocatalytic activity in the oxidative degradation of metronidazole and chloramphenicol drugs, as well as a promethrin herbicide in an aqueous medium exceeding known analogs. The possibilities of MC and SC in the synthesis of zinc and bismuth molybdates with the obtaining of their nanostructures with different morphologies, in particular bars, needles, rods, and spheres, are shown. It is established that prepared samples demonstrate high activity in the processes of ethanol oxidation to acetaldehyde (β-ZnMoO4) or acetic acid (α-ZnMoO4), oxidative dehydrogenation of hydrocarbons of the industrial fraction of oil processing with the obtaining of 1,3-butadiene (Bi2Mo3O12). [ABSTRACT FROM AUTHOR]

A cobalt(II) perchlorate hexahydrate coordinated synthesis of dihydropyrimidin‐ones and ‐thiones through sonochemistry is developed. Herein, the reaction was demonstrated as a simple, efficient, and one‐pot method for synthesizing a series of interesting 3,4‐dihydropyrimidin‐2(1H)‐ones. Further, the reaction mechanism was investigated using mass spectrometry and density functional theory calculations suggesting that a Lewis acid character of cobalt(II) perchlorate hexahydrate plays a crucial role in coordinating carbonyl functionalities and stabilizing the polar intermediates like imine–enamine which further led to cyclized dihydropyrimidin‐ones and ‐thiones. This methodology was further explored to synthesize a gram‐scale synthesis of monastrol drug, a kinase inhibitor. [ABSTRACT FROM AUTHOR]

The impact of hydrostatic pressure, commonly known as ambient or external pressure, on the phenomenon of sonochemistry and/or sonoluminescence has been extensively investigated through a multitude of experimental and computational studies, all of which have emphasized the crucial role played by this particular parameter. Numerous previous studies have successfully demonstrated the existence of an optimal static pressure for the occurrence of sonoluminescence and multi-bubble or single-bubble sonochemistry. However, despite these findings, a universally accepted value for this critical pressure has not yet been established. In addition, it has been found that the cavitation effect is completely inhibited when the static pressure is either too high or too low. This comprehensive review aims to delve into the primary experimental results and elucidate their significance in relation to hydrostatic pressure. We will then conduct an analysis of numerical calculations, focusing specifically on the influence of external pressure on single bubble sonochemistry. By delving into these calculations, we will be able to gain a deeper understanding of the experimental results and effectively interpret their implications.

Our study reports the ultrasound-assisted synthesis of SnS and SnS2 in the form of nanoparticles using aqueous solutions of respective tin chloride and thioacetamide varying sonication time. The presence of both compounds is confirmed by powder X-ray diffraction, energy-dispersive X-ray spectroscopy, as well as Raman and FT-IR spectroscopic techniques. The existence of nanoparticles is proven by powder X-ray diffraction investigation and by high resolution transmission electron microscopy observations. The size of nanocrystallites are in the range of 3–8 nm and 30 50 nm for SnS, and 1.5–10 nm for SnS2. X-ray photoelectron spectroscopy measurements, used to investigate the chemical state of tin and sulphur atoms on the surface of nanoparticles, reveal that they are typically covered with tin on the same oxidation degree as respective bulk compound. Values of optical bandgaps of synthesized nanoparticles, according to the Tauc method, were 2.31, 1.47 and 1.05 eV for SnS (60, 90 and 120 min long synthesis, respectively), and 2.81, 2.78 and 2.70 eV for SnS2 (60, 90 and 120 min long synthesis, respectively). Obtained nanoparticles were utilized as photo- and sonocatalysts in the process of degradation of model azo-dye molecules by UV-C light or ultrasound. Quantum dots of SnS2 obtained under sonication lasting 120 min were the best photocatalyst (66.9 % color removal), while quantum dots of SnS obtained under similar sonication time were the best sonocatalyst (85.2 % color removal).

A green, convenient, and scalable synthesis of alcohols through the reduction of aldehydes and ketones has been developed. The green reduction was conducted using two different methods, namely sonochemistry and mechanochemistry. In the former method, the solution of aldehydes or ketones and sodium borohydride was irradiated under ultrasound irradiation. In the latter technique, the reaction mixture was ground under solvent-free conditions. The reduction reaction was performed at room temperature and completed in only 10 min using both protocols. The results showed that aldehydes and ketones with aromatic, heteroaromatic, and aliphatic motifs were tolerated under the reaction conditions, allowing the formation of the corresponding alcohols with the synthetic yields of 75–98% and 77–95% for grinding and sonication methods, respectively. In addition, the reaction can be carried out on a multigram scale.

The extreme environment formed during bubble collapse can cause a series of chemical reactions inside the bubble, and multiple products (i.e., ˙OH, H˙, O, H2, and HO2˙, etc.) are produced, which is called sonochemistry. In this study, a new model is used to predict the sonochemistry characteristics inside an oxygen bubble oscillating in water. The influences of static pressure, ultrasonic frequency, and the equilibrium radius on the temperature inside the bubble and the yields of chemical products are analyzed. The numerical calculation results are obtained during bubble oscillations under a steady state, which is different from the previous studies that focus on the sonochemical characteristics at the bubble collapse. Numerical studies show that with the change in the equilibrium radius, the maximum bubble temperature fluctuates drastically, and the maximum yields of H2 and ˙OH show a Gaussian curve trend. The cavitation activity corresponding to the equilibrium radius depends on the combination of static pressure and ultrasonic frequency.

NbSe2 nanoparticles, the representative member of the VB TMDCs group, have garnered significant attention due to their unique structural and optical properties, which make them promising candidates for various applications in nanoelectronics and optoelectronics. In this paper, the authors report on the synthesis of NbSe2 nanoparticles via the sonochemical method at ambient temperature with controlled size, well-defined crystal structure, and desirable optical properties. The investigation of the compositional and structural analysis revealed that the synthesized nanoparticles are well-defined, near stoichiometry, with a hexagonal crystal structure belonging to the space group P63mmc. The other morphological and optical characteristics of the synthesized nanoparticles studied through scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), UV-VIS NIR spectroscopy, etc., were discussed here. [ABSTRACT FROM AUTHOR]

The present work is based on a mathematical model describing a single acoustic cavitation bubble oscillating under an ultrasonic field of 200 and 300 kHz and an acoustic amplitude of 1.8 atm within 1-butyl-3-methylimidazolium acetate. The model integrates the dynamics of bubble oscillation, the thermodynamics applied to the interior of the bubble and at its interface, and the sonophysical and sonochemical events occurring in the presence of dissolved cellulose in the ionic liquid. The performed simulations shed light on the major physical effects of acoustic cavitation, namely the shockwave and microjet, as well as the sonochemical effects in terms of the degradation rate of the dissolved cellulose in the secondary reactional site, i.e., the interface. The predominance of the effects and its dependency of the acoustic frequency is tackled from an energetic point of view. It is demonstrated that 300 kHz offers the lowest heat flow across the bubble interface, lowering the chances for the sonochemical degradation of cellulose, while 200 kHz offers a significant degradation rate, attaining 71.4 mol·dm−3·s−1, as well as harsher microjets and shockwaves with powers of 3300 and 900 mW at collapse, respectively. [ABSTRACT FROM AUTHOR]

Currently, in the context of biorefinery and bioeconomy, lignocellulosic biomass is increasingly used to produce biofuels, biochemicals and other value-added products. Microwaves and ultrasound are emerging techniques that enable efficient and environmentally sustainable routes in the transformation of lignocellulosic biomass. This review presents some of the most important works published in the last few years on the application of microwaves and/or ultrasound in lignocellulosic materials pretreatment and can be used as a starting point for research into this theme. This review is divided into four parts. In Part I, the theoretical fundamentals of microwave and ultrasound treatments are reviewed. Dielectric constants for biomass, factors that influence pretreatment, are some of the subjects addressed. In Part II, the effects that these techniques have on lignocellulosic biomass (on the size and surface area of the particle; on the content of lignin, hemicellulose and cellulose; on the crystallinity index of cellulose; on the effect of solubilization of organic matter; on hydrolysis and reduction of sugars) are discussed. In Part III, emphasis is given to the contribution of microwaves and ultrasound in obtaining value-added products. In this context, several examples of liquefaction and extraction procedures are presented. Part IV describes examples of performing sonocatalysis on lignocellulosic biomass to obtain value-added products, such as furfural, whose production is significantly reduced by ultrasound treatment. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) oxides have been the focus of substantial research interest recently, owing to their fascinating physico‐chemical properties. However, fabrication of large‐area 2D oxide materials in a controlled manner under mild conditions still remains a formidable challenge. Herein, we develop a facile and universal strategy based on the sonochemistry approach for controllable and large‐area growth of quasi‐aligned single‐crystalline ZnO nanosheets on a Zn substrate (Zn@SC‐ZnO) under ambient conditions. The obtained ZnO nanosheets possess the desired exclusively exposed (001¯ $\mathop{1}\limits^{̅}$) facets, which have been confirmed to play a critical role in significantly reducing the activation energy and facilitating the stripping/plating processes of Zn. Accordingly, the constructed Zn@SC‐ZnO||Zn@SC‐ZnO symmetric cell has very low polarization overpotential down to ~20 mV, with limited dendrite growth and side reactions for Zn anodes. The developed Zn@SC‐ZnO//MnO2 aqueous Zn‐ion batteries (ZIBs) show a voltage efficiency of 88.2% under 500 mA g−1 at the stage of 50% depth of discharge, which is state of the art for ZIBs reported to date. Furthermore, the as‐assembled large‐size cell (5 cm × 5 cm) delivers an open circuit potential of 1.648 V, and can be robustly operated under a high current of 20 mA, showing excellent potential for future scalable applications. [ABSTRACT FROM AUTHOR]

Sonochemistry is a specialized field dedicated to investigating ultrasound-promoted (US-promoted) chemical reactions and exploring new applications of US radiation. In recent years, US has been used as a valuable and practical tool combined with emerging porous solids, including metal–organic frameworks, crystalline covalent organic frameworks, and amorphous porous organic polymers, which belong to a family of new functional materials. This review highlights the sonosynthesis of porous solids and explores their use in sonochemical applications, including sonocatalysis and sonodynamic therapy. Moreover, this review presents the first comprehensive introduction to the use of sonochemistry in porous organic material applications. [ABSTRACT FROM AUTHOR]

Previously unknown C60 fullerene-fused 1,4-oxathian-2-ones 1,9-[2′-oxo-1′,4′-oxathiano]-1,9-dihydro-(C60-Ih)[5,6]fullerene and 1,9-[3′-Methyl-2′-oxo-1′,4′-oxathiano]-1,9-dihydro-(C60-Ih)[5,6]fullerene were obtained by a selective reaction mercaptocarboxylic acids (mercaptoacetic and 2-mercaptopropionic) with fullerene epoxide C60O in the presence of NaOH in an inert atmosphere at room temperature under ultrasonication for 1 h. The yields of the target product were estimated at 96 and 87%, respectively (by HPLC). A plausible reaction mechanism for was proposed. [ABSTRACT FROM AUTHOR]

The adsorption of cationic (methylene blue, MB) and anionic (Congo red, CR) dyes using magnetic from Archidendron pauciflorum peel extract obtained via sonochemical synthesis (Fe3O4-AP) has been carried out. This study also compared the ability of Fe3O4-AP as an adsorbent for MB and CR through isotherm and kinetics studies. Fe3O4-AP was synthesized by the sonochemical method at a frequency of 800 kHz and characterized using FTIR, XRD, PSA, VSM and SEM-EDX The XRD diffractogram showed Fe3O4-AP with high crystallinity with a crystal size of 17.05 nm, and the particle size distributed in three groups, 2.56, 862.23, and 4855.78 nm, respectively. Meanwhile, the Ms of Fe3O4-AP was 27.71 emu/g. The SEM-EDX showed disordered morphology with Fe, O and C elemental composition. The kinetics and isotherm of MB and CR dye adsorption on Fe3O4-AP followed Ho's kinetics model and Freundlich isotherm. The Freundlich isotherm model with adsorption capacities MB and CR on Fe3O4-AP was 16.02 and 10.24 mg/g, respectively. [ABSTRACT FROM AUTHOR]

An investigation into the mechanisms of action on bacteria involving exposure to stress factors was conducted in this study. The effects of ultrasound on Escherichia coli K-12 MG1655 and its isogenic mutant, ∆gadW, under high power ultrasound treatments (26 kHz) were screened and identified by analysing their transcriptome differences between primary and secondary sequential treatments using RNA-Seq. This also helped to assess any developed protection for cells between different generations. According to our results, 1825 genes of all tested conditions were expressed, playing different roles in the cell. The expression of these genes is associated with DNA damage, cell membrane integrity, and also metabolic effects. The studied strains also showed different differential expressed genes (DEGs), with some genes being directly responsible for defence mechanisms, while others play an indirect effect due to cell damage. A gradual decrease in the expression of the genes, as we moved from just one cycle of ultrasound treatment to sequential treatment, was evident from a heat map analysis of the results. Overall, E. coli K-12 builds a self-protection mechanism by increasing the expression of genes involved in the respiration for increased growth, and production of flagellum and pili. It can be concluded that high power ultrasound is a technology that triggers several different defence mechanisms which directly link to E. coli. [ABSTRACT FROM AUTHOR]

An ultrasound‐assisted method with specific characteristics of green chemistry for aerobic oxidative coupling of thiols to disulfides is presented. In this method, a readily available ionic liquid catalyzed the aerobic oxidative coupling of thiols to disulfides in water as a green solvent under ultrasonic irradiation at room temperature. In this novel sonocatalysis/ionic liquid protocol, aromatic thiols having both electron‐donating and electron‐withdrawing substituents, alkyl thiols and cysteine, were cleanly converted to the corresponding disulfides in excellent yields. This methodology uses 1,3‐dimethyl imidazolium methyl sulfate (DiMIM‐CH3SO4) ionic liquid as a recyclable catalyst and aerobic oxygen as an oxidative agent. This protocol has the advantages of high yields, short reaction times, lower cost, environmentally friendly reaction media, easy isolation of products, convenient procedure and recoverability of catalyst. [ABSTRACT FROM AUTHOR]

A novel chalcone containing (hetero)aromatic units was obtained by the Claisen-Schmidt condensation of phenothiazinyl-3-carbaldehyde with 4-hydroxy-acetophenone under three experimental approaches based on classical, mechanochemical and ultrasound-assisted procedures. A comparison between the experimental outcomes emphasizes shorter reaction time and lower energy usage in the case of mechanochemical and ultrasound-assisted procedures, recommending these methods as more environmentally friendly synthetic options. Moreover, the use of the sonochemical method resulted in the formation of the reaction product in crystalline state thus simplifying the purification process. The optical properties of the new chalcone were assessed by UV-vis spectroscopy. (E)-1-(4-hydroxyphenyl)-3-(10-methyl-10H-phenothiazin-3-yl)prop-2-en-1-one exhibited an intense absorption in the UV region (γmax=408 nm) and low intensity fluorescence emission in DMSO solution (γem=560 nm, Stokes shift 7558 cm-1). The X-ray diffraction on monocrystal technique which was employed to ascertain the solid-state structure of the new chalcone revealed strong O-H···O hydrogen bonds and weak dispersive van der Waals interactions such as π···π and C-H···π contacts ensuring its supramolecular architecture, crystal cohesion and stability. [ABSTRACT FROM AUTHOR]

With this manuscript we aim to initiate a discussion specific to educational actions around ultrasonics sonochemistry. The importance of these actions does not just derive from a mere pedagogical significance, but they can be an exceptional tool for illustrating various concepts in other disciplines, such as process intensification and microfluidics. Sonochemistry is currently a far-reaching discipline extending across different scales of applicability, from the fundamental physics of tiny bubbles and molecules, up to process plants. This review is part of a special issue in Ultrasonics Sonochemistry, where several scholars have shared their experiences and highlighted opportunities regarding ultrasound as an education tool. The main outcome of our work is that teaching and mentorship in sonochemistry are highly needed, with a balanced technical and scientific knowledge to foster skills and implement safe protocols. Applied research typically features the use of ultrasound as ancillary, to merely enhance a given process and often leading to poorly conceived experiments and misunderstanding of the actual effects. Thus, our scientific community must build a consistent culture and monitor reproducible practices to rigorously generate new knowledge on sonochemistry. These practices can be implemented in teaching sonochemistry in classrooms and research laboratories. We highlight ways to collectively provide a potentially better training for scientists, invigorating academic and industry-oriented careers. A salient benefit for education efforts is that sonochemistry-based projects can serve multidisciplinary training, potentially gathering students from different disciplines, such as physics, chemistry and bioengineering. Herein, we discuss challenges, opportunities, and future avenues to assist in designing courses and research programs based on sonochemistry. Additionally, we suggest simple experiments suitable for teaching basic physicochemical principles at the undergraduatelevel. We also provide arguments and recommendations oriented towards graduate and postdoctoral students, in academia or industry to be more entrepreneurial. We have identified that sonochemistry is consistently seen as a ‘green’ or sustainable tool, which particular appeal to process intensification approaches, including microfluidics and materials science. We conclude that a globally aligned pedagogical initiative and constantly updated educational tools will help to sustain a virtuous cycle in STEM and industrial applications of sonochemistry.

Large scale production of electrocatalysts for electrochemical energy conversion devices such as proton exchange membrane fuel cells must be developed to reduce their cost. The current chemical reduction methods used for this synthesis suffer from problems with achieving similar particle properties such as particle size and catalytic activity when scaling up the volume or the precursor concentration. The continuous production of reducing agents through the sonochemical synthesis method could help maintain the reducing conditions (and also the particle properties) upon increasing the reactor volume. In this work we demonstrate that the reducing conditions of Pt-nanoparticles are indeed maintained when the reactor volume is increased from 200 mL to 800 mL. Similar particle sizes, 2.1(0.3) nm at 200 mL and 2.3(0.4) nm at 800 mL, and catalytic activities towards the oxygen reduction reaction (ORR) are maintained as well. The reducing conditions were assessed through TiOSO4 dosimetry, sonochemiluminesence imaging, acoustic power measurements, and Pt(II) reduction rate measurements. Cyclic voltammetry, CO-stripping, hydrogen evolution measurements, ORR measurements, and electron microscopy were used to evaluate the catalytic activity and particle size. The similar particle properties displayed from the two reactor volumes suggest that the sonochemical synthesis of Pt-nanoparticles is suitable for large scale production.

In the last two decades, ultrasound (US) technologies research has increasingly earned attention for applications in the oil and gas industry. Numerous laboratory and field research have proven ultrasonics as an efficient, sustainable and cost-effective technology for improving well productivity. This paper pursues the elaboration of a comprehensive review of the most recent research related to ultrasonic technologies for applications in the oil and gas industry. Statistical analysis of different functional categories and classification of the research publications were performed. Considering the research reviewed, there is a huge gap between numerical and field studies in comparison with the numerous laboratory studies, deeming it necessary to increase efforts on developing mathematical and numerical models and field-testing cases of the ultrasonic effect. A comprehensive review of the ultrasonic waves’ mechanisms of action for enhanced oil recovery (EOR) and emulsification/demulsification was conducted. Despite the lack of consensus regarding the mechanisms, cavitation and thermal effects on wellbore fluid and formation rock have been widely accepted as two of the most influencing mechanisms. A compilation of the state-of-the-art research of numerical, laboratory and field studies in the last two decades was assembled. Most authors agreed that ultrasonics is a highly efficient method for EOR and emulsion treatment if the optimal conditions are identified and achieved. The development of screening criteria for the application of ultrasonic waves was recommended, as this technique and the same parameters should not be utilized for all reservoir types. Treatment with ultrasound waves has shown improvement of oil recovery efficiency rates of over 90% and viscosity reduction values over 80%. The most efficient results were observed when in combination with another conventional EOR method, where ultrasound boosts recovery efficiency. Potential new applications related to rock mechanics and additional research topics were also recommended.

Ultrasonic irradiation serves as a vigorous and environmentally sustainable approach for augmenting multicomponent reactions (MCRs), offering benefits such as thermal enhancement, agitation, and activation, among others. Malononitrile emerges as a versatile reagent in this context, participating in a myriad of MCRs to produce structurally diverse heterocyclic frameworks. This review encapsulates the critical role of malononitrile in the sonochemical multicomponent synthesis of these heterocyclic structures. The paper further delves into the biochemical and pharmacological implications of these heterocycles, elucidating their reaction mechanisms as well as delineating the method's scope and limitations. We furnish an overview of the merits and challenges inherent to this synthetic approach and offer insights for potential avenues in future research.