Search Results (9)

In this study, a novel and rapid top-down synthesis method for the successful synthesis of few-layered 2D SiC is reported. Since the theoretical prediction of planar and stable 2D SiC with a direct bandgap, only a few experimental methods have overcome the challenging covalent sp³ hybridization of its bulk structure, unlike Van der Waals layered material bonding, making the synthesis of few-layered or mono-layered SiC more difficult due to the highly time- and energy-consuming methods. Moreover, correctly choosing between the more than 250 SiC polytypes increases the complexity of successful approaches to its 2D synthesis. This work reports, for the first time, multi-layered 2D SiC obtained using the wet ultrasonic probe sonochemical exfoliation method, reducing both the experimental synthesis time and energy consumption. Raman spectra showed the size-dependent correlation of the longitudinal optical (LO) mode, and IR showed the bond modification between bulk and nanostructured SiC. These results demonstrate a scalable and facile route for 2D SiC production; therefore, a wide variety of applications can be explored experimentally rather than theoretically, and methods such as the deposition of ScAlN layers onto SiN can be simplified in further studies. Full article

Borophene, a two-dimensional (2D) allotrope of boron, has emerged as a highly promising material owing to its exceptional mechanical strength, electronic conductivity, and diverse structural phases. Unlike graphene and other 2D materials, borophene exhibits inherent anisotropy, flexibility, and metallicity, offering unique opportunities for advanced nanotechnological applications. This review presents a comprehensive summary of recent progress in borophene synthesis methods, highlighting both bottom–up strategies such as chemical vapor deposition (CVD) and molecular beam epitaxy (MBE), and top–down approaches, including liquid-phase exfoliation and sonochemical techniques. A key challenge discussed is the stabilization of borophene’s polymorphs, as bulk boron’s non-layered structure complicates exfoliation. The influence of substrates and doping strategies on structural stability and phase control is also explored. Moreover, the intrinsic physicochemical properties of borophene, including its high flexibility, oxidation resistance, and anisotropic charge transport, were examined in relation to their implications for electronic, catalytic, and sensing devices. Particular attention was given to borophene’s performance in hydrogen storage and hydrogen evolution reactions (HERs), where functionalization with alkali and transition metals significantly enhances H₂ adsorption energy and storage capacity. Studies demonstrate that certain borophene–metal composites, such as Ti- or Li-decorated borophene, can achieve hydrogen storage capacities exceeding 10 wt.%, surpassing the U.S. Department of Energy targets for hydrogen storage materials. Despite these promising characteristics, large-scale synthesis, long-term stability, and integration into practical systems remain open challenges. This review identifies current research gaps and proposes future directions to facilitate the development of borophene-based energy solutions. The findings support borophene’s strong potential as a next-generation material for clean energy applications, particularly in hydrogen production and storage systems. Full article

Theoretical studies have indicated that borophene is a promising two-dimensional material characterized by remarkable chemical, mechanical, and electrical properties. Nonetheless, its practical applications in areas such as catalysis and gas sensing are hindered by the limited density of reactive sites in its pristine form. To address this limitation, the present study explores the controlled fluorination of borophene nanoflakes as a strategy to modify their surface chemistry and enhance the availability of active sites. Furthermore, it is anticipated that surface fluorination will improve hydrophobicity, which is crucial for reducing humidity-related interference in sensing applications. In this study, we report the successful functionalization of borophene nanoflakes with fluorine using a plasma arc discharge technique for the first time. Borophene nanolayers were synthesized via a sonochemical-assisted exfoliation method, yielding nanosheets with an average lateral dimension of approximately 100 nm. The fluorinated samples were characterized using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM). A systematic investigation of plasma exposure durations demonstrated that fluorine was effectively introduced as a dopant while maintaining the crystallinity of the borophene lattice. Full article

The scientific field of two-dimensional (2D) nanostructures has witnessed tremendous development during the last decade. To date, different synthesis approaches have been developed; therefore, various exceptional properties of this family of advanced materials have been discovered. It has recently been found that the natural surface oxide films of room-temperature liquid metals is an emerging platform for the synthesis of novel types of 2D nanostructures with numerous functional applications. However, most of the developed synthesis techniques for these materials are based on the direct mechanical exfoliation of 2D materials as research targets. This paper reports a facile and functional sonochemical-assisted approach for the synthesis of 2D hybrid and complex multilayered nanostructures with tunable characteristics. In this method, the intense interaction of acoustic waves with microfluidic gallium-based room-temperature liquid galinstan alloy provides the activation energy for synthesis of hybrid 2D nanostructures. The microstructural characterizations reveal the impact of sonochemical synthesis parameters, including the processing time and composition of the ionic synthesis environment, on the growth of Ga_xO_y/Se 2D hybrid structures and InGa_xO_y/Se multilayered crystalline structures with tunable photonic characteristics. This technique shows promising potential for synthesis of various types of 2D and layered semiconductor nanostructures with tunable photonic characteristics. Full article

Understanding graphene oxide’s stability (or lack thereof) in liquid solvents is critical for fine-tuning the material’s characteristics and its potential involvement in future applications. In this work, through the use of structural and surface investigations, the alteration of the structural and edge-surface properties of 2D graphene oxide nanosheets was monitored over a period of eight weeks by involving DLS, zeta potential, XRD, XPS, Raman and FT-IR spectroscopy techniques. The samples were synthesized as an aqueous suspension by an original modified Marcano-Tour method centred on the sono-chemical exfoliation of graphite. Based on the acquired experimental results and the available literature, a phenomenological explanation of the two underlying mechanisms responsible for the meta-stability of graphene oxide aqueous dispersions is proposed. It is based on the cleavage of the carbon bonds in the first 3–4 weeks, while the bonding of oxygen functional groups on the carbon lattice occurs, and the transformation of epoxide and hydroxyl groups into adsorbed water molecules in a process driven by the availability of hydrogen in graphene oxide nanosheets. Full article

Laser photothermal-conversion membranes have great potential applications in many different fields, including laser ignition. However, the demand for real-time, high heat output calls for an extra heat-releasing pattern other than the traditional luminous energy–thermal, energy-conversion mechanism. Herein, it was found that fluorinated graphene (FG) was a promising candidate for laser photothermal conversion due to the extra chemical energy–thermal, energy-conversion process, which originated from a self-redox reaction under laser irradiation. Moreover, an easy sonochemical, exfoliation–filtration protocol was provided for the preparation of the fluorinated, graphene-based, free-standing membranes. In brief, FG flakes were arranged into flower-like patterns and formed freestanding, carpet-like membranes with layered structures with the filtration of FG suspension, which was obtained from exfoliating fluorographite in N-methylpyrrolidone. Furthermore, this contribution also revealed that modifying the FG membranes with polytetrafluoroethylene (PTFE) was helpful for improving the photothermal-conversion properties. With the construction of the FG/PTFE composited structure, higher heat output could be achieved when a laser pulse is applied to the composite membranes. This work revealed the great potential of fluorinated graphene in laser photothermal conversion, and provided an alternative route of introducing a chemical energy–thermal, energy-conversion process for achieving high heat output under laser irradiation. Full article

In this work, g-C₃N₄/TiO₂ composites were fabricated through a hydrothermal method for the efficient photocatalytic degradation of imidacloprid (IMI) pesticide. The composites were fabricated at varying loading of sonochemically exfoliated g-C₃N₄ (denoted as CNS). Complementary characterization results indicate that the heterojunction between the CNS and TiO₂ formed. Among the composites, the 0.5CNS/TiO₂ material gave the highest photocatalytic activity (93% IMI removal efficiency) under UV-Vis light irradiation, which was 2.2 times over the pristine g-C₃N₄. The high photocatalytic activity of the g-C₃N₄/TiO₂ composites could be ascribed to the band gap energy reduction and suppression of photo-induced charge carrier recombination on both TiO₂ and CNS surfaces. In addition, it was found that the active species involved in the photodegradation process are OH• and holes, and a possible mechanism was proposed. The g-C₃N₄/TiO₂ photocatalysts exhibited stable photocatalytic performance after regeneration, which shows that g-C₃N₄/TiO₂ is a promising material for the photodegradation of imidacloprid pesticide in wastewater. Full article

Due to modernization and the scarcity of fossil fuel resources, energy demand is continuously increasing. In this regard, it is essential and necessary to create a renewable energy source that can meet future energy demands. Recently, the production of H₂ by water splitting and removing pollutants from the water has been essential for issues of energy and environmental demands. Herein, g-C₃N₄ and Ag-g-C₃N₄ composite structures have been successfully fabricated by the ultrasonication method. The physio/photochemical properties of prepared g-C₃N₄ and Ag-g-C₃N₄ were examined with different analytical techniques such as FTIR, XRD, UV-DRS, SEM, TEM, PL, and XPS analyses. The silver quantum dots (QDS) anchored to g-C₃N₄ structures performed the profound photocatalytic activities of H₂ production, dye degradation, and antimicrobial activity under visible-light irradiation. The Ag/g-C₃N₄ composite with an Ag loading of 0.02 mole has an optimum photoactivity at 335.40 μmol g⁻¹ h⁻¹, which is superior to other Ag loading g-C₃N₄ composites. The synthesized Ag/g-C₃N₄ nanoparticles showed potential microbial inhibition activity during the preliminary screening, and the inhibition zones were comparable to the commercial antibiotic chloramphenicol. The loading of Ag into g-C₃N₄ paves the suppression, recombination and transfer of photo-generated electron-hole pairs, leading to the enhancement of hydrogen production, the diminishment of pollutants in water under visible light irradiation, and antimicrobial activity against multidrug-resistant pathogens. Full article

Graphene-based materials are highly interesting in virtue of their excellent chemical, physical and mechanical properties that make them extremely useful as privileged materials in different industrial applications. Sonochemical methods allow the production of low-defect graphene materials, which are preferred for certain uses. Graphene nanosheets (GNS) have been prepared by exfoliation of a commercial micrographite (MG) using an ultrasound probe. Both materials were characterized by common techniques such as X-ray diffraction (XRD), Transmission Electronic Microscopy (TEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). All of them revealed the formation of exfoliated graphene nanosheets with similar surface characteristics to the pristine graphite but with a decreased crystallite size and number of layers. An exhaustive study of the particle size distribution was carried out by different analytical techniques such as dynamic light scattering (DLS), nanoparticle tracking analysis (NTA) and asymmetric flow field flow fractionation (AF4). The results provided by these techniques have been compared. NTA and AF4 gave higher resolution than DLS. AF4 has shown to be a precise analytical technique for the separation of GNS of different sizes. Full article