INTRODUCTION TO 2D MATERIALS
Two-dimensional (2D) materials are one of the most exciting discoveries in cutting-edge materials science in the last two decades. Also known as monolayer materials, these materials are composed of a single layer of atoms (between 1-10) arranged in a lattice structure, making them single dimension in the nanoscale or smaller. 2D materials exhibit a massive ratio of surface area to volume, making them more reactive and efficient than their bulk counterparts, and can be layered to impart additional novel properties. Applications for American Elements 2D materials are nearly endless, including thin-film photovoltaics, microlectronics, advanced battery and supercapacitor technology, optics, bioengineering, environmental remediation, and plasmonics/metamaterials. Below is an overview of the most important 2D materials discovered so far.
Graphene was the first 2D material discovered. Graphene is structured as a single plane of sp2-bonded carbon atoms arranged in a hexagonal honeycomb lattice, with each atom bonded to 3 others. Graphene is notable for its extreme properties: it is 100-300 times stronger than steel and exhibits excellent electrical conductivity, approaching that of a superconductor at room temperature; it is optically transparent, absorbing only 2% of visible light; it is ultralight, flexible and stretchable, and possesses the highest tensile strength of any known material. Since its discovery, numerous other forms of graphene have been synthesized including graphene oxide, reduced graphene oxide, and doped forms with elements such as nitrogen and sulfur. Researchers have also discovered numerous "Xenes," structural analogs of graphene composed other elements such as Silicene (silicon), Stanene (tin), Germanene (germanium), Phosphorene (black phosphorus), Plumbene (tin), Borophene (boron), Antimonene (antimony), and Bismuthene (bismuth). American Elements offers a comprehensive catalog of standard and custom-synthesized graphene products; dopants and fuctionalized forms are available by request.
Hexagonal Boron Nitride (2D-hBN)
2D Hexagonal boron nitride is an isomorph of graphene, possessing the same crystal structure, though it exhibits different properties. h-BN is a wide-band gap (~ 5.9 eV) insulator with excellent thermal conductivity and mechanical robustness, making it a useful gate dielectric with applications in field effect transistors (FETs), tunneling devices, deep UV emitters and detectors, photoelectric devices, and nanofillers. Layering graphene on a hexagonal boron nitride substrate (Boron Nitride Nanosheets, BNNS), enhances electron mobility and improves thermal stability. American Elements h-BN products include thin films, single crystals, nanopowder, and other custom forms.
Transition Metal Dichalcogenides (TMDCs) & Trichalcogenides (TMTCs)
Transition Metal Dichalcogenides (TMDCs) have the chemical formula MX2, where M is a transition metal (such as molybdenum or tungsten) and X is a chalcogen (such as sulfur, selenium, or tellurium). Examples include molybdenum disulfide (MoS2), molybdenum diselenide (MoSe2), tungsten disulfide (WS2), and tungsten diselenide (WSe2). Similarly, molecules of transition metal trichalcogenides (TMTCs) possess three chalcogen atoms. Examples include as bismuth selenide (Bi2Se3), bismuth sulfide (Bi2S3), and zirconium triselenide (ZrSe3). Bulk TMDCs and TMTCs are van der Waals materials consisting of metallic atom layers sandwiched between chalcogenide atom layers. These materials are semiconductors with tunable band gaps, and layering different materials yields hybrid heterostructures that opens the field of materials science to hundreds of new types of metamaterials with tightly controlled properties.
MXenes are a novel type of two-dimensional (2D) ceramic composed of layered nitrides, carbides, or carbonitrides of transition metals. MXenes are notable for their properties that combine aspects of both metals and ceramics. These include excellent thermal and electrical conductivity, heat resistance, easy machinability, and excellent volumetric capacitance, having the highest EMI shielding effectiveness of all similar synthetic 2D materials, and hydrophobic natures due to various surface functional groups. For more information on the AE MXenes™ catalog of products, click here.
American Elements offers a full catalog of high purity and ultra high purity (up to 99.9999%) 2D materials and bulk precursors for the synthesis of novel 2D materials. Materials are produced via mechanical or liquid exfoliation, solution-based wet chemical synthesis, and chemical vapor deposition (CVD) and can be manufactured to customer specifications. Forms include single crystals, powders, flakes, and monolayer thin films. American Elements engineers can provide guidance on materials selection, properties, and applications. For more information on American Elements 2D materials, contact firstname.lastname@example.org.