Abstract: A photodiode comprising a photoactive spinel oxide layer is described. This photoactive spinel oxide layer forms a contact with both a light absorption layer of quantum dots, quantum wires, or quantum rods, and an inorganic substrate layer. In some embodiments, the inorganic substrate layer and the photoactive spinel oxide layer form an isotype junction. Methods of characterizing the photodiode are provided and demonstrate commercially relevant electrical and optoelectronic properties, particularly the ability to operate as a photodetector with a high photosensitivity. An economical process for preparing the photodiode is provided as well as applications.

Abstract: A graphene oxide based electrochemical cell and a battery containing a plurality of electrochemical cells, at least one of which is the graphene oxide based electrochemical cell. The graphene oxide based electrochemical cell includes an aqueous electrolyte solution, an anode and a cathode contained in a vessel, wherein the aqueous electrolyte solution includes water, graphene oxide nanosheets and CuCl2 dissolved in the water.

Abstract: A variable capacitor device and a method of preparation thereof, wherein the variable capacitor device comprises a shape-memory polymer in its dielectric layer, wherein the shape-memory polymer determines the thickness of the dielectric layer, thereby causing the capacitance of the variable capacitor device to be tuned. Various embodiments of the variable capacitor device and the method of preparing said capacitor have also been provided.

Abstract: A method for preparation of a dual phase filler for elastomers for manufacturing technical rubber items, including such for microwave protection. The method involves the following stages: first stage—1/10 of the silicasol impregnating solution obtained by its dilution in distilled water at a 1:10 ratio is pulverized over the carbon black at constant stirring; second stage—the carbon black pulverized with the silicasol impregnating solution is let stay in air at room temperature for 24 hours; third stage: a two-step thermal activation in a drying cabinet is carried out—at first at 80° C. for 2 hours, and then at 250° C. for 2 hours; fourth stage—9/10 of the impregnating solution that remained from the first stage is pulverized successively over the already impregnated carbon black at constant stirring. It again is let stay for 24 in air at room temperature; fifth stage: a three-step thermal activation in a drying cabinet is carried out—at first at 80° C. for 2 hours, then at 150° C.

Abstract: A composite material for electromagnetic interference shielding is provided. The composite material comprises a polymer matrix with metal nanoparticles dispersed within the matrix. Methods of characterizing the nanocomposites are provided and demonstrate commercially relevant mechanical and electrical properties, particularly an electromagnetic interference shielding effectiveness in the microwave frequency. An economical process for preparing the nanocomposites is also provided.

Abstract: The method for fabricating a hybrid dual phase filler for elastomers includes: impregnation of carbon black with ethanol suspension of magnetite in a ball mill; drying of the dual phase mixture till constant weight; grinding of the dried product in a ball mill; thermal activation under vacuum in a specifically designed reactor followed by a grinding of the final product in a ball mill. The hybrid dual phase filler includes carbon black impregnated with ethanol suspension of magnetite, contains 5 to 50 mass % of magnetite and 95 to 50 mass % of carbon black. Magnetite is a powder and includes up to 5% of SiO2, particle size up to 50? and density of 4.8-5.2 g/cm3 with a specific surface area (BET/) 400-900 m2/g; iodine number—370-750 mg/g; oil number 200-450 ml/100 g; total volume pore 0.5-1.5 cm3(STP)/g; micropore surface area 50-90 m2/g; external specific surface area 400-900 m2/g.

Abstract: A photoresponse device comprising a nanocomposite photoactive material is provided. The photoactive layer comprises a nanocomposite material of metal oxide nanoparticles dispersed within a photosensitizing organic semiconductor formed on a substrate. Methods of characterizing the nanocomposites are provided and demonstrate commercially relevant electrical and photodetection properties, particularly the ability to operate as a photodiode, photoconductor or photocapacitor. An economical process for preparing the nanocomposite and the photoresponse device is also provided as well as applications.

Abstract: A composition of graphene oxide free-standing film, a method of making the film, and a method of using the film to shield electromagnetic radiation particularly at microwave frequencies from 1 GHz to 12 GHz. The composition comprises stacked layers of graphene oxide nanosheets oriented parallel to the film surface and stacked layers of graphene oxide nanosheets oriented perpendicular to the film surface. The method of making the composition includes forming graphene oxide by arc-discharge between graphite electrodes in the presence of oxygen gas to form a graphene oxide soot, suspending the graphene oxide soot in water to form a colloid, depositing the colloid onto a substrate to form a wet paper, and drying the wet paper to form the film. The method of using the composition to shield electromagnetic radiation includes enclosing and/or encapsulating an electromagnetic radiation generating source with the free-standing film to shield electromagnetic radiation.

Abstract: A photoresponse device comprising a nanocomposite photoactive material is provided. The photoactive layer comprises a nanocomposite material of metal oxide nanoparticles dispersed within a photosensitizing organic semiconductor formed on a substrate. Methods of characterizing the nanocomposites are provided and demonstrate commercially relevant electrical and photodetection properties, particularly the ability to operate as a photodiode, photoconductor or photocapacitor. An economical process for preparing the nanocomposite and the photoresponse device is also provided as well as applications.

Abstract: A graphene oxide based electrochemical cell and a battery containing a plurality of electrochemical cells, at least one of which is the graphene oxide based electrochemical cell. The graphene oxide based electrochemical cell includes an aqueous electrolyte solution, an anode and a cathode contained in a vessel, wherein the aqueous electrolyte solution includes water, graphene oxide nanosheets and CuCl2 dissolved in the water.

Abstract: A method for preparation of a dual phase filler for elastomers for manufacturing technical rubber items, including such for microwave protection. The method involves the following stages: first stage—1/10 of the silicasol impregnating solution obtained by its dilution in distilled water at a 1:10 ratio is pulverized over the carbon black at constant stirring; second stage—the carbon black pulverized with the silicasol impregnating solution is let stay in air at room temperature for 24 hours; third stage: a two-step thermal activation in a drying cabinet is carried out—at first at 80° C. for 2 hours, and then at 250° C. for 2 hours; fourth stage—9/10 of the impregnating solution that remained from the first stage is pulverized successively over the already impregnated carbon black at constant stirring. It again is let stay for 24 in air at room temperature; fifth stage: a three-step thermal activation in a drying cabinet is carried out—at first at 80° C. for 2 hours, then at 150° C.

Abstract: A composite material for electromagnetic interference shielding is provided. The composite material comprises a polymer matrix with metal nanoparticles dispersed within the matrix. Methods of characterizing the nanocomposites are provided and demonstrate commercially relevant mechanical and electrical properties, particularly an electromagnetic interference shielding effectiveness in the microwave frequency. An economical process for preparing the nanocomposites is also provided.