41 results about "In situ chemical reduction" patented technology

Optically transparent, conductive polymer compositions and methods for making them are claimed. These conductive polymer compositions comprise an oxidized 3,4-ethylenedioxythiopene polymer, a polysulfonated styrene polymer, single wall carbon nanotubes and/or metallic nanoparticles. The conductive polymer compositions can include both single wall carbon nanotubes and metallic nanoparticles. The conductive polymer compositions have a sheet resistance of less than about 200 Ohms/square, a conductivity of greater than about 300 siemens/cm, and a visible light (380-800 nm) transmission level of greater than about 50%, preferably greater than about 85% and most preferably greater than about 90% (when corrected for substrate). The conductive polymer compositions comprising single wall carbon nanotubes are made by mixing the oxidized 3,4-ethylenedioxythiopene polymer and polysulfonated styrene polymer with single wall carbon nanotubes and then sonicating the mixture. The conductive polymer compositions comprising metallic nanoparticles are made by a process of in situ chemical reduction of metal precursor salts.

The invention relates to a graphene/cotton cloth flexible conducting fabric and a preparing method of the graphene/cotton cloth flexible conducting fabric. The graphene/cotton cloth flexible conducting fabric is prepared through the following steps of adsorbing oxidized graphene through cotton fabrics, and then performing in-situ chemical reduction. An impregnation-drying method is used for covering the oxidized graphene on the surface of the cotton fabric fiber; then, an in-situ chemical reduction method is used for reducing the oxidized graphene into graphene, so that the cotton fabric has good conducting performance. The applied method has the advantages that the use of surfactants, auxiliary agents and toxic substances is avoided; the preparing method belongs to a safe, simple, convenient, green, energy-saving and environment-friendly preparing method.

The invention belongs to the technical fields of materials and biology, and in particular relates to a surface-enhanced Raman scattering (SERS) tag microsphere and a preparation method thereof. The preparation method comprises the following steps of: reducing silver nitrate solution by using a reducing agent by taking a polymer microsphere of which the surface is provided with a carboxyl functional group as a template by an in-situ chemical reduction method to prepare a composite microsphere with uniform and compact surface silver nanoparticle coverage degree; and cladding a silicon dioxide shell by using a chemical adsorption Raman probe molecule and a silane coupling agent by a sol-gel method to obtain the SERS tag microsphere with high SERS activity. The SERS tag microsphere has monodispersity, high stability and high biocompatibility, a silicon dioxide surface is easily modified into functional groups such as an amino group or carboxyl and the like, and the SERS tag microsphere is chemically combined with a biomolecule and is applied to the fields of immunoassay, biomedical imaging, disease treatment and the like. The method is easy to operate, and has a controllable process and a good application prospect.

The invention discloses hybridized particles, a polymer-based composite material, their preparation methods and a use of the polymer-based composite material. The hybridized particles comprise insulating ceramic particles and conductive microparticles loaded on the surfaces of the insulating ceramic particles. The conductive microparticles are granularly and discretely distributed on the surfaces of the insulating ceramic particles. The preparation method of the hybridized particles adopts an in-situ chemical-reduction technology, a sol-gel technology, an in-situ polymerization technology, a high-temperature heat treatment technology or a mechanical milling technology. The polymer-based composite material comprises the hybridized particles and a polymer filled with the hybridized particles. The polymer-based composite material comprises 20-80wt% of the hybridized particles. The hybridized particles have stable structures and stable performances. The polymer-based composite material has the excellent performances such as high dielectric constant, low dielectric loss and stable performances. The preparation methods of the hybridized particle and the polymer-based composite material have the advantages of simple process, easy control of conditions, high production efficiency and industrial production applicability.

The preparation method of Pt-Ru series CO resistant electrode catalyst is characterized by that it uses carbon nano tube as carrier, utilizes the in-situ chemical reduction homogeneous precipitation method and makes the ions of Pt, Ru and Sn into compounding ion respectively (called complex ion for short), then it uses two kinds of three kinds of complex ions and mixes them together to obtain metastable colloid, them adopts cheap reduction agent formaldehyde (or sodium borohydride or ethyl alcohol or hydrogen gas) to make the metastable colloid be reduced and deposited on the activated carbonnano tube so as to obtain the invented electrode catalyst for proton-exchange membrane fuel cell. It possesses good electric catalytic activity and resistance to Co, and features large specific area,high porosity, good dispersion property and low ptatinum use level.

The invention discloses a fuel cell catalyst taking multi-element compound as a carrier and a preparation method thereof, relating to a fuel cell catalyst and a preparation method thereof. The fuel cell catalyst of the invention adopts the mixed material of a granular carbon material (C1) and a linear carbon material (C2) as a carbon basal material; a precipitation thermal decompositing method is carried out on the two basal materials to prepare a compound carrier MOx-(C1+C2) of a carbon carrier and an oxide; an in-situ chemical reduction method is carried to prepare a Pt/MOx-(C1+C2) catalyst; MOx is CeO2, SnO2, Co3O4 or NiO; C1 is carbon black, carbon microsphere or mesoporous carbon; C2 is carbon fiber or carbon nanometer tube; the linear carbon material is combined with the granular carbon material to form a three-dimensional compound network structure, so as to increase the three-phase reaction activity area of the catalyst; and the doped metal oxide enhances the anti-CO capacity of the catalyst, and improves the use ratio of platinum.

The invention belongs to the technical field of function materials, and specifically relates to a Raman strengthening active microsphere and a preparation method and an application thereof. The Raman strengthening active microsphere provided by the invention has a core-shell structure, the core of the Raman strengthening active microsphere is a melamine resin microsphere, and the shell is uniform and compact silver nanometer granules. The preparation method comprises the steps of firstly preparing uniform melamine-oxymethylene microsphere through fasculation, then utilizing a reducing agent to restore silver nitrate through a normal position chemical reduction method, and uniformly and compactly depositing the generated silver nanometer granules onto the surface of the melamine resin microsphere, so as to prepare the MF/Ag-NPs composite microsphere. The raman strengthening active microsphere utilizes a single microsphere as a raman strengthening base material, and is used for detecting Raman. The single Raman strengthening active base material microsphere provided by the invention has the characteristics of high stability and high Raman strengthening property. The method provided by the invention has the advantages that the operation is simple, the process is controllable, and the prepared composite microsphere can be used for analyzing and detecting organic contaminants such as pesticide residue of a single microsphere in a Raman manner.

The invention discloses a preparation method of an antibacterial dressing for promoting wound healing, comprising the following steps of: carrying out pretreatment on flocculent bacterial cellulose obtained by utilizing a dynamic zymotechnics, and then uniformly implanting nano silver on the bacterial cellulose surface by utilizing an in-situ chemical reduction method to obtain a bacterial cellulose nano silver composite material; and placing the bacterial cellulose nano silver composite material into a hyaluronic acid solution for dipping, dehydrating the bacterial cellulose for adsorbing hyaluronic acid, and carrying out a coupling reaction by utilizing carbodiimide to form a bacterial cellulose/hyaluronic acid-loaded nano silver composite material. The composite material has the effects of a controlled release bacteriacide for controlling wound infection and interaction between cells and a substrate and promoting wound healing. In the invention, a composite film is prepared through bacterial cellulose/hyaluronic acid-loaded nano silver, high flexibility of a bacterial cellulose substrate and favorable skin adhesiveness are exerted, and the antibacterial dressing has the antibacterial effect of promoting wound healing and can be used for preparing multipurpose drug wound dressings for accelerating wound repairing.

The invention discloses a nano zero-valent iron modified porous cobaltosic oxide heterogeneous persulfate catalyst, and a preparation method and an application thereof. The preparation method for synthesizing the porous cobaltosic oxide heterogeneous persulfate catalyst by using a nano zero-valent iron modified yeast template technology comprises the following steps: firstly, synthesizing cobaltosic oxide microspheres with high specific surface area and porosity in a high-temperature environment by using Saccharomyces cerevisiae as a biological template; and loading nano zero-valent iron on the surface by an in-situ chemical reduction technology. The synthesized final catalyst is a heterogeneous iron-cobalt bimetallic composite material, and can effectively catalyze peroxydisulfate, whichhas a symmetrical structure and is difficult to activate, through the synergistic circulation effect between ions with different valence states of cobalt and iron. A generated active free radical group (SO4<.->/.OH) can quickly and efficiently attack tetracycline molecules of antibiotics, and finally mineralize the tetracycline molecules into carbon dioxide and water molecules, so that the catalyst has certain practical application values.

The invention provides a flexible base material and a preparation method thereof. Compared with the prior art that a sputtering(or chemical plating)/ electric plating method is utilized to prepare the adhesive-free flexible base material, the method utilizes a normal position chemical reduction/ electric plating method to prepare the flexible base material on an insulation base material containing a surface layer, and the surface layer contains nanometer particles with micropore structure. First, a middle layer is subjected to the normal position chemical reduction, partial metal particles are infiltrated into micro pores of the nanometer particles to enable physical anchoring fit to be formed between the middle layer and the insulation base material and improve peeling strength. Further, the peeling strength is not reduced after high temperature processing. Second, the particles are in nanometer grade, the insulation base material infiltrated in the middle layer is shallow, interface is smooth, etching performance is good, and manufacture of a fine line is facilitated. Finally, the normal position chemical reduction method can control thickness of the middle layer by adjusting density of oxygen liquid and reduction liquid and spraying time to further prepare the adhesive-free flexible base material with any thickness without special devices, and the preparation process is simple.

The invention belongs to the technical field of corrosion inhibition of ocean engineering concrete structure metal materials, and particularly relates to a photo-anode film for reinforcing steel bar photoelectric cathode protection and a preparation method and application thereof. The preparation method comprises the following steps: with ferric salt and urea as raw materials, preparing Fe2O3 on a conductive surface of a clean conductive substrate through a hydrothermal method; making polyaniline deposited on the surface of Fe2O3 through an electrochemical synthesis method to prepare a Fe2O3-PANI composite photo-anode film; and preparing the Ru-Fe2O3-PANI composite photo-anode film on the surface of the Fe2O3-PANI composite photo-anode film through an in-situ chemical reduction method. According to the technical scheme, efficient photoelectric cathode protection of the ocean engineering concrete reinforcement can be achieved, and the durability of an ocean engineering concrete structure is improved.

The invention relates to the field of catalysts, and particularly discloses a nitrogen-doped graphene-carbon nanotube composite catalyst and a preparation method thereof. The invention discloses the nitrogen-doped graphene-carbon nanotube composite catalyst. The catalyst comprises a carbon carrier and noble metal loaded on the carbon carrier; the carbon carrier is composed of nitrogen-doped reduced graphene oxide and a nitrogen-doped carbon nanotube; the preparation method comprises the following steps: mixing nitrogen-doped reduced graphene oxide with a noble metal precursor solution, and depositing noble metal on the nitrogen-doped reduced graphene oxide to obtain noble metal-loaded nitrogen-doped reduced graphene oxide; and combining the nitrogen-doped carbon nanotube with the noble metal-loaded nitrogen-doped reduced graphene oxide through an in-situ chemical reduction method to obtain the nitrogen-doped graphene-carbon nanotube composite catalyst. The nitrogen-doped graphene-carbon nanotube composite catalyst provided by the invention can be used for a fuel cell, and has the advantages of high catalytic activity and high stability; in addition, the preparation method has the advantages of being simple, large in yield and suitable for batch production.

The invention discloses a polytrifluoropropyl methyl siloxane/silver composite surface enhanced Raman substrate and a preparation method thereof. According to the method, by means of the enrichment effect of polytrifluoropropyl methyl siloxane on nitrobenzene pollutants, a sol-gel method and an in-situ chemical reduction method are combined to form silver nanoparticles on the surface of a polytrifluoropropyl methyl siloxane film, wherein the silver nanoparticles are uniform in particle size and compact in arrangement; and therefore, the polytrifluoropropyl methyl siloxane/silver composite surface enhanced Raman substrate can be prepared. The polytrifluoropropyl methyl siloxane film in the composite surface enhanced Raman substrate has a good enrichment effect on nitro pollutants in water and does not cause any interference to measurement. The polytrifluoropropyl methyl siloxane/silver composite surface enhanced Raman substrate has the advantages of good repeatability, controllable process, high sensitivity and low cost, and can be used for the surface-enhanced Raman spectroscopy measurement of various substances.