Abstract: Conformable and wearable sensors with integrated on-chip gate for the detection of biomolecules, chemicals, and other substrates and applications thereof are provided. Biosensor chips can be built with In2O3 nanoribbon field-effect transistors. Biosensor chips can conform to features of a human body, enabling ability for individuals to wear a biosensor.

Abstract: A biosensor capable of detecting both the SARS-CoV-2 S1 spike protein antigen and the SARS-CoV-2 spike protein IgG antibody is disclosed. In various embodiments, the biosensor is configured with an array of solution-gated nanoribbon FETs, wherein each nanoribbon comprises indium oxide (In2O3). In various aspects, the biosensor is fabricated using a scalable and cost-efficient lithography-free process comprising shadow masking.

Abstract: Conformable and wearable sensors with integrated on-chip gate for the detection of biomolecules, chemicals, and other substrates and applications thereof are provided. Biosensor chips can be built with In2O3 nanoribbon field-effect transistors. Biosensor chips can conform to features of a human body, enabling ability for individuals to wear a biosensor.

Abstract: A method for forming an anode of a sodium ion battery includes a step of heat treating the red phosphorus precursor and reduced graphene oxide powder at a first temperature that vaporizes the red phosphorus precursor such that red phosphorus structures grow on the reduced graphene oxide powder. Another method for forming an anode of a sodium ion battery includes steps of placing a red phosphorus precursor and a graphene oxide precursor in a reaction chamber; establishing a reducing environment in the reaction chamber; and heating the red phosphorus precursor and a graphene oxide precursor to a first temperature that is sufficient temperature to form a composite of red phosphorus and reduced graphene oxide. Characteristically, red phosphorus deposition and graphene oxide reduction are completed simultaneously in a single-step heat treatment. A method for making a black phosphorus-composite for sodium-ion batter anodes is also provided.

Abstract: Conformable and wearable sensors with integrated on-chip gate for the detection of biomolecules, chemicals, and other substrates and applications thereof are provided. Biosensor chips can be built with In2O3 nanoribbon field-effect transistors. Biosensor chips can conform to features of a human body, enabling ability for individuals to wear a biosensor.

Abstract: The experimental realization of a non-volatile artificial synapse using organic polymers in a scalable fabrication process is provided. The three-terminal electrochemical neuromorphic device successfully emulates the key features of biological synapses: long-term potentiation/depression, spike-timing-dependent plasticity learning rule, paired-pulse facilitation, and ultralow energy consumption. The artificial synapse network exhibits excellent endurance against bending tests and enables a direct emulation of logic gates, which shows the feasibility of using them in futuristic hierarchical neural networks. Based on the demonstration of 100 distinct, non-volatile conductance states, high accuracy in pattern recognition and face classification neural network simulations is achieved.

Abstract: A method of separating and extracting carbon nanotubes, the method includes introducing the carbon nanotubes into a two-phase system that includes a first component and a second component, the first component being different from the second component. The method includes introducing a chemical agent into the two-phase system, mixing the chemical agent and the carbon nanotubes in the two-phase system, removing the first component to extract a first portion of the carbon nanotubes contained in the first component after the mixing, replenishing the two-phase system with fresh first component, and extracting a second portion of the carbon nanotubes contained in the fresh first component. A bandgap of the carbon nanotubes in the first portion is different from the bandgap of the carbon nanotubes in the second portion.

Abstract: Systems and methods for using an indium oxide field-effect transistor. A method includes applying phosphonic acid to a nanoribbon of the indium oxide field-effect transistor. The method also includes preparing the nanoribbon with capture antibodies corresponding to a biomarker. The method also includes applying a fluid sample containing at least one biomarker to the nanoribbon. The method also includes preparing the nanoribbon with secondary antibodies corresponding to the biomarker. The method also includes applying a protein solution to the nanoribbon. The method also includes detecting the presence of the at least one biomarker when a reactive solution is applied to the nanoribbon.

Abstract: The inventors experimentally demonstrated NO2 gas sensing performance of multilayer black phosphorous (BP) field effect transistors. The BP sensors were sensitive to NO2 concentration down to 5 ppb making them comparable in sensitivity to the best 2D material based sensors. Raman spectroscopy comparison revealed no apparent change in the spectra before and after exposure to NO2, which shows that thick BP flakes can maintain their relative stability after sensing. Moreover, the BP device sensing performance fitted well with the Langmuir Isotherm for molecules adsorbed on a surface, which confirms charge transfer as the dominant mechanism for sensing. The systematic increase in conductance with increasing NO2 concentrations suggests NO2 molecules withdraw electrons and dope BP flakes with holes. These results lay the ground work for BP to be applied to various sensing applications including chemical, gas, and bio-sensors.

Abstract: A method for forming an anode of a sodium ion battery includes a step of heat treating the red phosphorus precursor and reduced graphene oxide powder at a first temperature that vaporizes the red phosphorus precursor such that red phosphorus structures grow on the reduced graphene oxide powder. Another method for forming an anode of a sodium ion battery includes steps of placing a red phosphorus precursor and a graphene oxide precursor in a reaction chamber; establishing a reducing environment in the reaction chamber; and heating the red phosphorus precursor and a graphene oxide precursor to a first temperature that is sufficient temperature to form a composite of red phosphorus and reduced graphene oxide. Characteristically, red phosphorus deposition and graphene oxide reduction are completed simultaneously in a single-step heat treatment. A method for making a black phosphorus-composite for sodium-ion batter anodes is also provided.

Abstract: Systems and methods for fabricating indium oxide field-effect transistors. A method may include placing a first layer shadow mask having a first plurality of apertures onto a substrate. The method may further include depositing indium oxide through the first plurality of apertures and onto the substrate to form a plurality of indium oxide nanoribbons. The method may further include removing the first layer shadow mask. The method may further include placing a second layer shadow mask having a second plurality of apertures onto the substrate. The method may further include depositing a conductive material through the second plurality of apertures and onto the substrate to form a plurality of source and drain electrodes in electrical contact with the plurality of indium oxide nanoribbons. The method may further include removing the second layer shadow mask.

Abstract: An electrode for a lithium ion battery, the electrode including nanoporous silicon structures, each nanoporous silicon structure defining a multiplicity of pores, a binder, and a conductive substrate. The nanoporous silicon structures are mixed with the binder to form a composition, and the composition is adhered to the conductive substrate to form the electrode. The nanoporous silicon may be, for example, nanoporous silicon nanowires or nanoporous silicon formed by etching a silicon wafer, metallurgical grade silicon, silicon nanoparticles, or silicon prepared from silicon precursors in a plasma or chemical vapor deposition process. The nanoporous silicon structures may be coated or combined with a carbon-containing compound, such as reduced graphene oxide. The electrode has a high specific capacity (e.g., above 1000 mAh/g at current rate of 0.4 A/g, above 1000 mAh/g at a current rate of 2.0 A/g, or above 1400 mAh/g at a current rate of 1.0 A/g).

Abstract: A method of fabricating a thin film transistor, the method includes applying a first ink containing metallic particles to a first screen mask, and using the first screen mask to deposit the first ink to form a source electrode and a drain electrode on a substrate bearing a layer of carbon nanotubes (CNT). The method includes applying a second ink containing a dielectric material to a second screen mask, and using the second screen mask to deposit the second ink to form a layer of the dielectric material on the layer of CNT between the source electrode and the drain electrode. The method includes applying a third ink containing metallic particles to a third screen mask, and using the third screen mask to deposit the first ink to form a metallic gate electrode on the layer of the dielectric material to form the thin film transistor.

Abstract: A method of separating and extracting carbon nanotubes, the method includes introducing the carbon nanotubes into a two-phase system that includes a first component and a second component, the first component being different from the second component. The method includes introducing a chemical agent into the two-phase system, mixing the chemical agent and the carbon nanotubes in the two-phase system, removing the first component to extract a first portion of the carbon nanotubes contained in the first component after the mixing, replenishing the two-phase system with fresh first component, and extracting a second portion of the carbon nanotubes contained in the fresh first component. A bandgap of the carbon nanotubes in the first portion is different from the bandgap of the carbon nanotubes in the second portion.

Abstract: An electrode includes a first free-standing carbon network, an active material deposited above the first free-standing carbon network, and a second free-standing carbon network covering the active material. The first and second carbon networks are a binder, a conductive additive and a current collector to the electrode.

Abstract: The inventors experimentally demonstrated NO2 gas sensing performance of multilayer black phosphorous (BP) field effect transistors. The BP sensors were sensitive to NO2 concentration down to 5 ppb making them comparable in sensitivity to the best 2D material based sensors. Raman spectroscopy comparison revealed no apparent change in the spectra before and after exposure to NO2, which shows that thick BP flakes can maintain their relative stability after sensing. Moreover, the BP device sensing performance fitted well with the Langmuir Isotherm for molecules adsorbed on a surface, which confirms charge transfer as the dominant mechanism for sensing. The systematic increase in conductance with increasing NO2 concentrations suggests NO2 molecules withdraw electrons and dope BP flakes with holes. These results lay the ground work for BP to be applied to various sensing applications including chemical, gas, and bio-sensors.

Abstract: A method includes combining a coating material and an uncoated particulate core material in a solution having a selected ionic strength. The selected ionic strength promotes coating of the uncoated particulate core material with the coating material to form coated particles; and the coated particles can be collected after formation. The coating material has a higher electrical conductivity than the core material.

Abstract: A method for growing a graphene layer on a metal foil includes placing a vessel into a chemical vapor deposition chamber, the vessel having a metal foil positioned therein. The method includes evacuating the chemical vapor deposition chamber, introducing hydrogen gas into the chamber to achieve a first pressure less than atmospheric pressure, heating the atmosphere in the chamber to anneal the metal foil, introducing methane and hydrogen into the chamber to achieve a second pressure less than atmospheric pressure.

Abstract: The subject technology relates to a method including steps for disposing a first electrically conductive material on a substrate to form a first layer of electrodes on the substrate, wherein the first layer includes a source electrode and a drain electrode, and printing a film including carbon nanotubes between the source electrode and the drain electrode, thereby defining at least a first interface between the carbon nanotube film and the source electrode and a second interface between the carbon nanotube film and drain electrode. In certain aspects, the method can further include steps for disposing a second electrically conductive material over the first interface between the carbon nanotube film and the source electrode and the second interface between the carbon nanotube film and the drain electrode. In certain aspects, a transistor device is also provided.

Abstract: A method of fabricating a logic element, the method includes forming a p-type nanomaterial thin film transistor on a substrate, forming a n-type metal oxide thin film transistor on the substrate, and connecting the p-type nanomaterial thin film transistor to the n-type metal oxide thin film transistor to form the logic element. The logic element is a hybrid complementary logic element.