The present disclosure provides a three-dimensional hydrogel-graphene-based biosensor and a preparation method thereof, belonging to the technical field of biosensors. The present disclosure provides a three-dimensional hydrogel-graphene-based biosensor, including a substrate, an electrode layer, a graphene film, and a three-dimensional hydrogel material layer that are stacked in sequence; where the three-dimensional hydrogel material layer is formed of a hydrogel material having a three-dimensional network structure; the hydrogel material is obtained by polymerization of raw materials including an acrylamide monomer and a modified probe molecule; and the modified probe molecule is a probe molecule modified with an acrylamide group. The three-dimensional hydrogel-graphene-based biosensor has a desirable stability and a high sensitivity.

Provided are a composite structure, in which metal nanoparticle-perovskite oxide is bound to metal oxide supports (i.e., sensing materials), and a preparation method thereof. The composite structure has improved durability, in which metal nanoparticles uniform in size are evenly distributed on the surface of perovskite oxide. Provided is also a high-performance gas sensor having excellent target gas detection performances by including the composite structure.

Disclosed herein are methods of producing metal nanoparticle-decorated carbon nanotubes. The methods include forming a reaction mixture by combining a first solution with a second solution, wherein the first solution comprises polymer-coated metal nanoparticles comprising metallic nanoparticles coated with a polymer, and wherein the second solution comprises carbon nanotubes. The methods also include heating the reaction mixture to a temperature greater than a glass transition temperature of the polymer for a time sufficient to cause the polymer-coated metal nanoparticles to bind to the carbon nanotubes forming the metal nanoparticle-decorated carbon nanotubes.

Provided is a sensor with nanowires in an aligned array. In one example, the heaviest doped region is not in the nanowire array, but in the bulk silicon substrate and the sensor is functionalized to be have modified electrical properties when proteins are present.

A method of manufacturing a graphene-tin oxide nanocomposite comprises dispersing graphene and tin oxide in an organic solvent to prepare a dispersion solution, drying the dispersion solution to obtain a powdery mixture, and irradiating the mixture with microwaves to obtain a graphene-tin oxide nanocomposite. Irradiation of graphene and tin oxide with microwaves results in the simplification of the manufacturing process of graphene-tin oxide nanocomposites and a decrease in manufacturing time and cost, and produce graphene-tin oxide nanocomposites at low temperatures. Further, the graphene-tin oxide nanocomposite with improved sensitivity to NO2 gas may be produced.

A hydrogen gas sensor with a substrate and a zinc oxide nanostructured thin film deposited on the substrate, wherein the zinc oxide nanostructured thin film has a lattice structure with a weight ratio of low binding energy O.sup.2− ions to medium binding energy oxygen vacancies in a range of 0.1 to 1.0, and a method of fabricating a gas sensor by thermally oxidizing a metal thin film under low oxygen partial pressure. Various combinations of embodiments of the hydrogen gas sensor and the method of fabricating the gas sensor are provided.

Disclosed is a gas sensor. The gas sensor comprises: a substrate; a thermoelectric layer which is disposed on the substrate and has a metal nanowire; a first electrode and a second electrode disposed to be spaced apart from each other on the thermoelectric layer; and a catalyst layer which is disposed on the first electrode and has a composite structure in which a metal particle is bonded to a carbon structure.

To provide an odor sensor capable of using an additive that was not capable of being adopted in an odor sensor including a polymer film, an odor measurement system using the odor sensor, and a method for producing the odor sensor, an odor sensor comprises a plurality of sensor elements, the sensor element including a substance absorption film adsorbing an odor substance; and a detection unit detecting adsorption of the odor substance with respect to the substance absorption film, wherein the substance absorption film is a porous fine particle film that contains fine particles containing a compound having silicon and oxygen as a skeleton, and a surface modifier for modifying surfaces of the fine particles, and in at least a part of the plurality of sensor elements, compositions of the fine particles and/or the surface modifier are different from each other.

A system and method for direct and/or active detection and monitoring of civil engineering or other infrastructural structures, and in a preferred embodiment, for hydrocarbon leakage in oil and gas pipelines, storage structures, and/or transportation structures. Particularly, the system and method relate to various nanocomposite sensor coating and data gathering systems. In one embodiment, the apparatus includes a single measurement sensor coating (thin film) sensor. Other embodiments relate to multiple measurement sensor coating systems. The sensor is comprised of either a discrete conductive filament layer, or a single or multiple mesh of interwoven filaments of conductive material in one direction and nonconductive material in a perpendicular direction, as a substrate coated with sensitive coating materials to form a sensor grid. Various embodiments of the sensor coating and their applications are also disclosed.

A composite thread includes first and second segments joined to each other. The first segment comprises a functional segment that interacts with an environment of the thread. The second segment communicates information between the first segment and a point external to said composite thread.