We report on a fast and simple method to produce highly stable isopropanol/water (4:1) suspensions of few‐layer antimonene by liquid‐phase exfoliation of antimony crystals in a process that is ...assisted by sonication but does not require the addition of any surfactant. This straightforward method generates dispersions of few‐layer antimonene suitable for on‐surface isolation. Analysis by atomic force microscopy, scanning transmission electron microscopy, and electron energy loss spectroscopy confirmed the formation of high‐quality few‐layer antimonene nanosheets with large lateral dimensions. These nanolayers are extremely stable under ambient conditions. Their Raman signals are strongly thickness‐dependent, which was rationalized by means of density functional theory calculations.
Very stable suspensions of high‐quality single‐ or few‐layer antimonene were obtained by liquid‐phase exfoliation under sonication without the need for a surfactant. The Raman spectrum of antimonene was found to strongly depend on its thickness, which was also rationalized by quantum‐mechanical calculations.
Antimonene, a novel group 15 two‐dimensional material, is functionalized with a tailormade perylene bisimide through strong van der Waals interactions. The functionalization process leads to a ...significant quenching of the perylene fluorescence, and surpasses that observed for either graphene or black phosphorus, thus allowing straightforward characterization of the flakes by scanning Raman microscopy. Furthermore, scanning photoelectron microscopy studies and theoretical calculations reveal a remarkable charge‐transfer behavior, being twice that of black phosphorus. Moreover, the excellent stability under environmental conditions of pristine antimonene has been tackled, thus pointing towards the spontaneous formation of a sub‐nanometric oxide passivation layer. DFT calculations revealed that the noncovalent functionalization of antimonene results in a charge‐transfer band gap of 1.1 eV.
Flake off: Reported for the first time is the noncovalent functionalization of antimonene using perylene bisimides (PDI). The significant quenching of the fluorescence of the PDI allows straightforward characterization of the antimonene flakes deposited on Si/SiO2 substrates. This work paves the way for the development of novel applications based on antimonene by tailoring its electronic properties.
Abstract
Luminescent defects in hexagonal boron nitride (h-BN) have recently emerged as a promising platform for non-classical light emission. On-chip solutions, however, require techniques for ...controllable in-situ manipulation of quantum light. Here, we demonstrate the dynamic spectral and temporal tuning of the optical emission from h-BN via moving acousto-mechanical modulation induced by stimulated phonons. When perturbed by the propagating acoustic phonon, the optically probed radiative h-BN defects are periodically strained and their sharp emission lines are modulated by the deformation potential coupling. This results in an acoustically driven spectral tuning within a 2.5-meV bandwidth. Our findings, supported by first-principles theoretical calculations, reveal exceptionally high elasto-optic coupling in h-BN of ~50 meV/%. Temporal control of the emitted photons is achieved by combining the acoustically mediated fine-spectral tuning with spectral detection filtering. This study opens the door to the use of sound for scalable integration of h-BN emitters in nanophotonic and quantum information technologies.
The exfoliation of tridimensional crystal structures has recently been considered a new source of bidimensional materials. The new approach offers the possibility of dramatically enlarging the ...library of bidimensional materials, but the number of nanolayers produced so far is still limited. Here, we report for the first time the use of a new type of material, α-germanium nanolayers (2D α-Ge). The 2D α-Ge is obtained by exfoliating crystals of α-germanium in a simple one-step procedure assisted by wet ball-milling (gram-scale fabrication). The α-germanium nanolayers have been tested as anode material for high-performance LIBs. The results show excellent performance in semi-cell configuration with a high specific capacity of 1630 mAh g−1 for mass loading of 1 mg cm−2 at 0.1 C. The semi-cell was characterized by a constant current rate of 0.5 C during 400 cycles and different scan rates (0.1 C, 0.5 C, and 1 C). Interestingly, the structural characterization, including Raman spectroscopy, XRPD, and XPS, concludes that 2D α-Ge largely retains its crystallinity after continuous cycling. These results can be used to potentially apply these novel 2D germanium nanolayers to high-performance Li-ion batteries.
In pursuing higher energy density, without compromising the power density of supercapacitor platforms, the application of an advanced 2D nanomaterial is utilized to maximize performance. Antimonene, ...for the first time, is characterized as a material for applications in energy storage, being applied as an electrode material as the basis of a supercapacitor. Antimonene is shown to significantly improve the energy storage capabilities of a carbon electrode in both cyclic voltammetry and galvanostatic charging. Antimonene demonstrates remarkable performance with a capacitance of 1578 F g−1, with a high charging current density of 14 A g−1. Hence, antimonene is shown to be a highly promising material for energy storage applications. The system also demonstrates a highly competitive energy and power densities of 20 mW h kg−1 and 4.8 kW kg−1, respectively. In addition to the excellent charge storing abilities, antimonene shows good cycling capabilities.
Advanced nanomaterials have significant potential for applications in the energy storage field. A very stable to operating conditions, novel nanomaterial is presented here, for the first time, as an electrode material for energy storage architectures. Antimonene, a single or few‐layer material derived from bulk antimony, is, for the first time characterized as a nanomaterial suitable for energy storage applications.
Antimonene, a novel group 15 two‐dimensional material, is functionalized with a tailormade perylene bisimide through strong van der Waals interactions. The functionalization process leads to a ...significant quenching of the perylene fluorescence, and surpasses that observed for either graphene or black phosphorus, thus allowing straightforward characterization of the flakes by scanning Raman microscopy. Furthermore, scanning photoelectron microscopy studies and theoretical calculations reveal a remarkable charge‐transfer behavior, being twice that of black phosphorus. Moreover, the excellent stability under environmental conditions of pristine antimonene has been tackled, thus pointing towards the spontaneous formation of a sub‐nanometric oxide passivation layer. DFT calculations revealed that the noncovalent functionalization of antimonene results in a charge‐transfer band gap of 1.1 eV.
Maßgeschneiderte Flocken: Die nichtkovalente Funktionalisierung von Antimonen mit Perylenbisimid (PDI) wird beschrieben. Die starke Fluoreszenzlöschung von PDI ermöglicht die direkte Charakterisierung der auf Si/SiO2‐Substraten abgeschiedenen Antimonenflocken. Die Ergebnisse bereiten den Weg für neuartige Anwendungen auf Antimonenbasis durch die gezielte Justierung der elektronischen Eigenschaften.
We report on a fast and simple method to produce highly stable isopropanol/water (4:1) suspensions of few‐layer antimonene by liquid‐phase exfoliation of antimony crystals in a process that is ...assisted by sonication but does not require the addition of any surfactant. This straightforward method generates dispersions of few‐layer antimonene suitable for on‐surface isolation. Analysis by atomic force microscopy, scanning transmission electron microscopy, and electron energy loss spectroscopy confirmed the formation of high‐quality few‐layer antimonene nanosheets with large lateral dimensions. These nanolayers are extremely stable under ambient conditions. Their Raman signals are strongly thickness‐dependent, which was rationalized by means of density functional theory calculations.
Stabile Suspensionen aus hochwertigem, ein‐ oder mehrschichtigem Antimonen wurden durch Flüssigphasenexfoliation unter Ultraschallbehandlung erhalten, ohne dass ein Tensid benötigt wurde. Das Raman‐Spektrum von Antimonen hängt stark von dessen Dicke ab, was durch quantenmechanische Rechnungen bestätigt wurde.
2D materials have opened a new field in materials science with outstanding scientific and technological impact. A largely explored route for the preparation of 2D materials is the exfoliation of ...layered crystals with weak forces between their layers. However, its application to covalent crystals remains elusive. Herein, a further step is taken by introducing the exfoliation of germanium, a narrow‐bandgap semiconductor presenting a 3D diamond‐like structure with strong covalent bonds. Pure α‐germanium is exfoliated following a simple one‐step procedure assisted by wet ball‐milling, allowing gram‐scale fabrication of high‐quality layers with large lateral dimensions and nanometer thicknesses. The generated flakes are thoroughly characterized by different techniques, giving evidence that the new 2D material exhibits bandgaps that depend on both the crystallographic direction and the number of layers. Besides potential technological applications, this work is also of interest for the search of 2D materials with new properties.
α‐Germanium crystals are exfoliated using a wet ball‐milling technique to produce α‐germanium nanolayers (α‐Ge NLs) in a process that is upscaled to gram production. The α‐Ge NLs can be redispersed using a shear‐mixer, yielding very stable suspensions. Theoretical calculations predict a thickness‐dependent bandgap of these NLs that is confirmed by electron energy‐loss spectroscopy of α‐Ge NLs with different orientations.
2D materials show outstanding properties that can bring many applications in different technological fields. However, their uses are still limited by production methods. In this context, antimonene ...is recently suggested as a new 2D material to fabricate different (opto)electronic devices, among other potential applications. This work focuses on optimizing the synthetic parameters to produce high‐quality antimonene hexagons and their implementation in a large‐scale manufacturing procedure. By means of a continuous‐flow synthesis, few‐layer antimonene hexagons with ultra‐large lateral dimensions (up to several microns) and a few nanometers thick are isolated. The suitable chemical post‐treatment of these nanolayers with chloroform gives rise to antimonene surfaces showing low oxidation that can be easily contacted with microelectrodes. Therefore, the reported procedure offers a way to solve two critical problems for using antimonene in many applications: large‐scale preparation of high‐quality antimonene and the ability to set electrical contacts useful for device fabrication.
A continuous‐flow synthesis approach offers large‐scale preparation of high‐quality few‐layer antimonene (FLA) hexagons. This procedure is based on colloidal synthesis followed by a post‐treatment with chloroform to isolate FLA hexagons which present ultra‐large lateral dimensions and a few nanometers thickness. Mechanical and electrical analyses reveal their high‐quality and low surface oxidation, opening the door for applications in electronics and beyond.
PDF
