Abstract: 2D heterostructures comprising Bi2Se3/MoS2, Bi2Se3/MoSe2, Bi2Se3/WS2, Bi2Se3/MoSe2. 2xS2x, or mixtures thereof in which oxygen is intercalated between the layers at selected positions provide high density storage devices, sensors, and display devices. The properties of the 2D heterostructures can be configured utilizing abeam of electromagnetic waves or particles in an oxygen controlled atmosphere.

Abstract: The present technology provides devices and methods to determine the spectrum or other spectral characteristic, such as color, of a beam of light or other electromagnetic radiation. The beam of light or other electromagnetic radiation is modified without dispersion by broadband transmissive windows and then transmitted onto a detector. Signals from the detector are measured from a training set of radiation having known spectra and used to train the device, after which the device can estimate the spectrum or color of an unknown light or other electromagnetic radiation with exceptionally high accuracy.

Abstract: Devices and methods of the present technology utilize wavelength-dependent transmittance of 2D materials to identify the wavelength of an electromagnetic radiation. A wide range of 2D materials can be used, making possible the use of the technology over a large portion of the electromagnetic spectrum, from gamma rays to the far infrared. When combined with appropriate algorithms and artificial intelligence, the technology can identify the wavelength of one or more monochromatic sources, or can identify color through the use of a training set. When applied in an array format, the technology can provide color imaging or spectral imaging using different regions of the electromagnetic spectrum.

Abstract: Ultrasensitive, miniaturized, and inexpensive ion and ionizing radiation detection devices are provided. The devices include an insulating substrate, metallic contact pads disposed on a surface of the substrate, and a strip of an ultrathin two-dimensional material having a thickness of one or a few atomic layers. The strip is in contact with the contact pads, and a voltage is applied across the two-dimensional sensor material. Individual ions contacting the two-dimensional material alter the current flowing through the material and are detected. The devices can be used in a network of monitors for high energy ions and ionizing radiation.

Abstract: Methods for making of nanomaterials from a bulk source material involve heating the material in an inert atmosphere, whereby a material having at least one nanometer scale dimension is formed on a nearby substrate surface. The heated bulk source material forms a vapor phase which is deposited in the form of the nanomaterial on a growth surface of the substrate. The methods require no complex machinery or devices, unlike chemical vapor deposition, and can be tuned to provide different forms of nanomaterials, such as two-dimensional or other crystalline forms. The methods can be used to make two-dimensional semiconductor materials and semiconductor devices.

Abstract: Ion-doped two-dimensional nanomaterials are made by inducing electronic carriers (electrons and holes) in a two-dimensional material using a captured ion layer at the surface of the material. The captured ion layer is stabilized using a capping layer. The induction of electronic carriers works in atomically-thin two-dimensional materials, where it induces high carrier density of at least 1014 carriers/cm2. A variety of novel ion-doped nanomaterials and p-n junction-based nanoelectronic devices are made possible by the method.

Abstract: Heterocrystals of metal dichalcogenides and Bi2S3, Bi2Se3 or Bi2Te3 are presented, in which the metal dichalcogenides and Bi2S3, Bi2Se3 or Bi2Te3 do not largely retain their independent properties. These heterocrystals exhibit electronic and optical changes, which make them attractive for beyond-silicon electronics and optoelectronics. Particularly, these heterocrystals can be re-configured in a manner that allows bit writing and pattern drawing. Embodiments of these heterocrystals, methods of forming these heterocrystals, methods of reconfiguring the heterocrystals, information storage devices, optoelectronic circuits and photonic crystals are presented.

Abstract: 2D heterostructures comprising Bi2Se3/MoS2, Bi2Se3/MoSe2, Bi2Se3/WS2, Bi2Se3/MoSe2. 2xS2x, or mixtures thereof in which oxygen is intercalated between the layers at selected positions provide high density storage devices, sensors, and display devices. The properties of the 2D heterostructures can be configured utilizing abeam of electromagnetic waves or particles in an oxygen controlled atmosphere.

Abstract: Described herein are devices containing freestanding, ultrathin (<10 nm thick) membranes and methods of making such devices. Also described are methods of using devices containing freestanding ultrathin membranes for determining the sequence of a polynucleotide and for desalination of aqueous solutions.

Abstract: The invention provides methods for direct growth of low noise, atomically thin freestanding membranes of two-dimensional monocrystalline or polycrystalline materials, such as transition metal chalcogenides including molybdenum disulfide. The freestanding membranes are directly grown over an aperture by reacting two precursors in a chemical vapor deposition process carried out at atmospheric pressure. Membrane growth is preferentially over apertures in a thin sheet of solid state material. The resulting membranes are one or a few atomic layers thick and essentially free of defects. The membranes are useful for sequencing of biopolymers through nanopores.

Abstract: The invention provides methods for direct growth of low noise, atomically thin freestanding membranes of two-dimensional monocrystalline or polycrystalline materials, such as transition metal chalcogenides including molybdenum disulfide. The freestanding membranes are directly grown over an aperture by reacting two precursors in a chemical vapor deposition process carried out at atmospheric pressure. Membrane growth is preferentially over apertures in a thin sheet of solid state material. The resulting membranes are one or a few atomic layers thick and essentially free of defects. The membranes are useful for sequencing of biopolymers through nanopores.

Abstract: Inter-allotropic transformations of carbon are provided using moderate conditions including alternating voltage pulses and modest temperature elevation. By controlling the pulse magnitude, small-diameter single-walled carbon nanotubes are transformed into larger-diameter single-walled carbon nanotubes, multi-walled carbon nanotubes of different morphologies, and multi-layered graphene nanoribbons.

Abstract: Ion-doped two-dimensional nanomaterials are made by inducing electronic carriers (electrons and holes) in a two-dimensional material using a captured ion layer at the surface of the material. The captured ion layer is stabilized using a capping layer. The induction of electronic carriers works in atomically-thin two-dimensional materials, where it induces high carrier density of at least 1014 carriers/cm2. A variety of novel ion-doped nanomaterials and p-n junction-based nanoelectronic devices are made possible by the method.

Abstract: The invention provides methods for direct growth of low noise, atomically thin freestanding membranes of two-dimensional monocrystalline or polycrystalline materials, such as transition metal chalcogenides including molybdenum disulfide. The freestanding membranes are directly grown over an aperture by reacting two precursors in a chemical vapor deposition process carried out at atmospheric pressure. Membrane growth is preferentially over apertures in a thin sheet of solid state material. The resulting membranes are one or a few atomic layers thick and essentially free of defects. The membranes are useful for sequencing of biopolymers through nanopores.

Abstract: Ultrasensitive, miniaturized, and inexpensive ion and ionizing radiation detection devices are provided. The devices include an insulating substrate, metallic contact pads disposed on a surface of the substrate, and a strip of an ultrathin two-dimensional material having a thickness of one or a few atomic layers. The strip is in contact with the contact pads, and a voltage is applied across the two-dimensional sensor material. Individual ions contacting the two-dimensional material alter the current flowing through the material and are detected. The devices can be used in a network of monitors for high energy ions and ionizing radiation.

Abstract: Heterocrystals of metal dichalcogenides and Bi2S3, Bi2Se3 or Bi2Te3 are presented, in which the metal dichalcogenides and Bi2S3, Bi2Se3 or Bi2Te3 do not largely retain their independent properties. These heterocrystals exhibit electronic and optical changes, which make them attractive for beyond-silicon electronics and optoelectronics. Particularly, these heterocrystals can be re-configured in a manner that allows bit writing and pattern drawing. Embodiments of these heterocrystals, methods of forming these heterocrystals, methods of reconfiguring the heterocrystals, information storage devices, optoelectronic circuits and photonic crystals are presented.

Abstract: An ion detection device has a strip of carbon-based nanomaterial (CNM) film and a chamber enclosing the CNM film. A low bias voltage is applied at the ends of the CNM film strip, and ions present in the chamber are detected by a change in the magnitude of current flowing through the CNM film under the bias. Also provided are methods for fabricating the device, methods for measuring pressure of a gas, and methods for monitoring or quantifying an ionizing radiation using the device.

Abstract: The invention provides methods for direct growth of low noise, atomically thin freestanding membranes of two-dimensional monocrystalline or polycrystalline materials, such as transition metal chalcogenides including molybdenum disulfide. The freestanding membranes are directly grown over an aperture by reacting two precursors in a chemical vapor deposition process carried out at atmospheric pressure. Membrane growth is preferentially over apertures in a thin sheet of solid state material. The resulting membranes are one or a few atomic layers thick and essentially free of defects. The membranes are useful for sequencing of biopolymers through nanopores.

Abstract: Inter-allotropic transformations of carbon are provided using moderate conditions including alternating voltage pulses and modest temperature elevation. By controlling the pulse magnitude, small-diameter single-walled carbon nanotubes are transformed into larger-diameter single-walled carbon nanotubes, multi-walled carbon nanotubes of different morphologies, and multi-layered graphene nanoribbons.

Abstract: Devices contain freestanding, ultra thin (<10 nm thick) membranes and methods of making such devices. Methods of using devices contain freestanding ultra thin membranes for determining the sequence of a polynucleotide and for desalination of aqueous solutions. A device containing: a substrate having an upper surface, a lower surface, and an aperture, the aperture having one or more walls connecting the upper and lower surfaces and forming a well; and a membrane attached to the lower surface of the substrate and forming a floor of the well, the membrane having a thickness of less than 10 nm. The electrical conductance across the membrane is less than 1 nS/?m2.