Massachusetts Institute of Technology

King Fahd University of Petroleum and Minerals

Jing Kong

Lain-Jong Li

Tomas Apostol Palacios

Mildred S Dresselhaus

Xiang Ji

Yuxuan Lin

Hyesung Park

Karen K Gleason

Marc A Baldo

Sehoon Chang

Tahar Laoui

Rohit Nandkumar Karnik

Francesco Stellacci

Piran Ravichandran Kidambi

Silvija Gradecak

He Dong

Zhengtao Deng

Aishuang Xiang

Efren Navarro-Moratalla

Pin-Chun Shen

Qingqing Ji

Xi Ling

Yi-Hsien Lee

Zhenfei Gao

Sung Mi Jung

Rachel M Howden

Xiaogang (Bruno) Liu

Jikang Yuan

Yumeng Shi

Christoph Hamsen

Tian Ming

Alfonso Reina Cecco

Brian J Modtland

Ahmed Ibrahim

Sui Zhang

Devices, such as transistors, that use bismuth to create ohmic contacts are provided, as are methods of manufacturing the same. The transistors, such as field-effect transistors, can include one or more two-dimensional materials, and electrical contact areas can be created on the two-dimensional material(s) using bismuth. The bismuth can help to provide energy-barrier free, ohmic contacts, and the resulting devices can have performance levels that rival or exceed state-of-the-art devices that utilize three-dimensional materials, like silicon. The two-dimensional materials can include transition metal dichalcogenides, such as molybdenum disulfide.

Devices and methods for creating ohmic contacts using bismuth

Atomically thin layers including pores, their method of manufacture, and their use are disclosed. In some embodiments, pores may be formed in an atomically thin layer by growing the atomically thin layer on exposed portions of a substrate that includes islands comprising a material that is different than the material of the substrate. In some embodiments, pores and/or defects may be formed in an atomically thin layer by employing growth conditions that promote the formation of defects and/or pores. In certain embodiments, pores and/or defects may be etched to enlarge their size.

Formation of pores in atomically thin layers

In a method provided herein for forming a chalcogenide film on a substrate, an elemental solid is exposed to a hydrogen halide gas in a heated reaction environment at a temperature at which the hydrogen halide gas promotes the elemental solid to evolve into an elemental halide-based gas. The elemental halide-based gas is then exposed to a chalcogen gas provided in the heated reaction environment, at a temperature at which the elemental halide-based gas is reactive with the chalcogen gas to produce a solid chalcogenide reaction product. A substrate is provided in the heated reaction environment for deposition thereon of a solid film of the solid chalcogenide reaction product that results from exposure of the elemental halide-based gas to the chalcogen gas in the heated reaction environment.

In situ generation of gaseous precursors for chemical vapor deposition of a chalcogenide

A two-dimensional transition-metal dichalcogenide layer is grown by reacting a non- or low-volatile source material with a volatilized halogen or halide compound to produce a volatilized composition comprising at least one reaction product. The volatilized composition is flowed through an open chamber of a tube furnace with a temperature gradient, wherein the temperature changes along a path through which the volatilized composition flows through the open chamber of the tube furnace. Where the temperature along the path in the open chamber is in a reaction-temperature range, the volatilized composition is deposited as a two-dimensional crystalline transition-metal dichalcogenide layer.

Chemical vapor transport growth of two-dimensional transition-metal dichalcogenides

A thermo-mechanical bolometer includes a substrate and a sensing component mounted on the substrate. The sensing element comprises (a) at least one thermal-actuation component mounted in parallel with the substrate and (b) a strain sensor mounted on the at least one layer of thermal-actuation component. The at least one thermal-actuation component alone or in combination (a) absorbs electromagnetic waves and converts energy from absorbed electromagnetic waves into a change in temperature and (b) converts the change in temperature into a deformation of the at least one layer. The strain sensor comprises a layer of fragments with a gap space between the fragments, wherein the strain sensor senses the deformation or mechanical movement and exhibits a change in electrical resistance in response to the sensed deformation or mechanical movement.

Ultrasensitive thermo-mechanical bolometer

A method for preparing a core-shell nanocrystal can include mixing an M-containing precursor solution, an X-containing precursor solution, and an acid or alcohol in an inert atmosphere at a first temperature to form a reaction mixture; maintaining the reaction mixture at the first temperature to grow the MX core of the nanocrystal; raising the temperature of the reaction mixture to a second temperature; and maintaining the reaction mixture at the second temperature to grow a shell of the nanocrystal.

One-pot method for preparing core-shell nanocrystals

A transparent electrode can include a graphene sheet on a substrate, a layer including a conductive polymer disposed over the graphene sheet, and a plurality of semiconducting nanowires, such as ZnO nanowires, disposed over the layer including the conductive polymer.

Nanowire-modified graphene and methods of making and using same

A two-dimensional heterostructure is synthesized by producing a patterned first two-dimensional material on a growth substrate. The first two-dimensional material is patterned to define at least one void through which an exposed region of the growth substrate is exposed. Seed molecules are selectively deposited either on the exposed region of the growth substrate or on the patterned first two-dimensional material. A second two-dimensional material that is distinct from the first two-dimensional material is then grown from the deposited seed molecules.

Universal methodology to synthesize diverse two-dimensional heterostructures

Aromatic molecules are seeded on a surface of a growth substrate; and a layer (e.g., a monolayer) of a metal dichalcogenide is grown via chemical vapor deposition on the growth substrate surface seeded with aromatic molecules. The seeded aromatic molecules are contacted with a solvent that releases the metal dichalcogenide layer from the growth substrate. The metal dichalcogenide layer can be released with an adhered transfer medium and can be deposited on a target substrate.

Synthesis and transfer of metal dichalcogenide layers on diverse surfaces

Provided in one embodiment is a method of making an aerogel, comprising: (A) increasing a concentration of a suspension comprising a gel precursor under a condition that promotes formation of a gel, wherein the gel precursor comprises particulates having an asymmetric geometry; and (B) removing a liquid from the gel to form the aerogel, wherein the aerogel and the gel have substantially the same geometry. An aerogel comprising desirable properties are also provided.

Aerogels and methods of making same

The present invention generally relates to devices comprising graphene and a conductive polymer (e.g., poly(3,4-ethylenedioxythiophene) (PEDOT)), and related systems and methods. In some embodiments, the conductive polymer is formed by oxidative chemical vapor deposition.

Devices comprising graphene and a conductive polymer and related systems and methods

The present invention relates to coated, absorbent, freestanding assemblies comprising inorganic nanowires, articles of manufacture comprising the same, processes of producing the same and methods of use thereof. The assemblies of this invention are useful in various applications, including removal of organics or hydrophobic materials, and waterproofing applications.

Absorbant superhydrophobic materials, and methods of preparation and use thereof

A hexagonal boron nitride thin film is grown on a metal surface of a growth substrate and then annealed. The hexagonal boron nitride thin film is coated with a protective support layer and released from the metal surface. The boron nitride thin film together with the protective support layer can then be transferred to any of a variety of arbitrary substrates.

Fabrication of large-area hexagonal boron nitride thin films

A film of single-layer to few-layer graphene is formed by depositing a graphene film via chemical vapor deposition on a surface of a growth substrate. The surface on which the graphene is deposited can be a polycrystalline nickel film, which is deposited by evaporation on a SiO/Si substrate. A protective support layer is then coated on the graphene film to provide support for the graphene film and to maintain its integrity when it is removed from the growth substrate. The surface of the growth substrate is then etched to release the graphene film and the protective support layer from the growth substrate, wherein the protective support layer maintains the integrity of the graphene film during and after its release from the growth substrate. After being released from the growth substrate, the graphene film and protective support layer can be applied onto an arbitrary target substrate for evaluation or use in any of a wide variety of applications.

Growing community of inventors

Winchester, MA, United States of America

Jing Kong