104results about How to "Excellent capacitance performance" patented technology

The invention discloses a preparation method and an application of a nitrogen-doped carbon fiber/nitrogen-doped graphene/bacterial cellulose membrane material, relates to a preparation method and an application of a membrane material and aims to solve the problem that a flexible electrode material prepared with a conventional method does not have good stability, cycle performance and mechanical properties. The method comprises the following steps: preparing bacterial cellulose pulp; preparing a bacterial cellulose and graphene composite; preparing a polypyrrole coated bacterial cellulose and graphene composite; preparing a nitrogen-doped carbon fiber/nitrogen-doped graphene composite through high-temperature carbonization; preparing a nitrogen-doped carbon fiber/nitrogen-doped graphene dispersing agent; performing vacuum pumping filtration on the bacterial cellulose pulp for membrane forming, adding the dispersing agent for continuous pumping filtration for membrane forming, and performing vacuum drying for finishing. The membrane material has low equipment corrosion, low cost, good cycle performance and good mechanical properties and can realize scale production, and a symmetrical supercapacitor prepared from the membrane material has the good capacitive character. The invention belongs to the technical field of nanomaterials.

The invention relates to a preparation method and application of a N-P-dopted carbon fiber/graphene/bacterial cellulose conducting film material. The invention relates to a preparation method and application of a flexible electrode material and aims to solve the problem that a conducting film material prepared according to the existing method has poor stability, cycling performance and mechanical property. The preparation method disclosed by the invention comprises the following steps: preparing bacterial cellulose pulp; preparing N-P-dopted carbon fiber; preparing N-P-dopted carbon fiber/graphene composite dispersion liquid; carrying out vacuum filtering on bacterial cellulose pulp to form a film; and then adding the N-P-dopted carbon fiber/graphene composite dispersion liquid and further carrying out vacuum filtration to form a film; and finally drying in vacuum. The N-P-dopted carbon fiber/graphene/bacterial cellulose conducting film material is applied to a supercapacitor. The N-P-dopted carbon fiber/graphene/bacterial cellulose conducting film material can load high active matter mass in unit area, can be synthesized simply, has controllable electrical conductivity and good rate capability, can be put into large-scale production and can be used for preparing a symmetric supercapacitor with high capacitive character. The invention belongs to the technical field of nanomaterial.

The invention relates to a ZIF-8 pyrolysis porous carbon-graphene composite material, a manufacturing method and an application thereof. The structure of the composite material is characterized in that graphene is wrapped on a surface of ZIF-8 pyrolysis porous carbon. The manufacturing method comprises the following steps of mixing zinc nitrate hexahydrate and 2-methylimidazole and dissolving in a solvent; standing for 1-2hs and acquiring a milk-shape solution; centrifuging, washing, carrying out vacuum drying and acquiring ZIF-8 crystal; and mixing the ZIF-8 crystal and potassium citrate, grinding, carrying out high temperature carbonization and acid pickling, drying and acquiring the material. The manufacturing method is simple and cost is low. The acquired ZIF-8 pyrolysis porous carbon-graphene composite material possesses advantages that a chemical property is stable, a capacitive character is good, a specific surface area is high and so on. A hierarchical pore and a three-dimensional conducting framework are fully used to increase electrochemical performance. Under a 1A/g current density, a specific capacitance reaches 300F/g. The material is an ideal high performance electrode material of a super capacitor.

The invention provides a polyaniline nanometer tube array/graphene composite material electrode and a manufacturing method and application thereof, and belongs to the field of new energy products. The composite material electrode comprises a polyaniline nanometer tube array/graphene composite material and a conductive substrate. Graphene is doped in a polyaniline nanometer tube array to form a fiber-slice coexisting structure, the diameter of polyaniline nanometer tubes ranges from 150 nm to 300 nm, and the pipe spacing of the polyaniline nanometer tubes ranges from 300 nm to 400 nm. The conductive substrate is coated with the composite material to form the polyaniline nanometer tube array/graphene composite material electrode. The composite material electrode is high in conductivity and excellent in circulating performance and capacitance performance; the method for preparing the composite material electrode is easy to operate and friendly to the environment; a super capacitor with the composite material electrode is high in capacitance and good in circulating performance.

A device for protecting I/O lines using low capacitance steering diodes (1200) and PIN or NIP diodes (1202), (1203) is disclosed. A low capacitance diode arrangement configured as steering diodes protect a signal line or input/output (I/O) port (1201) from high voltage transients by diverting or directing the transient to either the positive side of the power supply line (1204) or to ground (1205).

The invention discloses an electrolyte mixture, a composition for conductive polymer synthesis and conductive polymer solid electrolytic capacitor formed by using the same. The electrolyte mixture includes a conductive polymer and a nitrogen-containing polymer. The nitrogen-containing polymer includes a cyclic nitrogen-containing polymer, a polymer with primary amine group, a polymer with secondary amine group, a polymer with tertiary amine group, a polymer with quaternary ammonium group, or a combination thereof. The interface impedance between the conductive polymer and the oxide film can be facilitated by additionally providing the cyclic nitrogen-containing polymer, and the filming performance of the conductive polymer can be improved, the conductivity of the conductive polymer can be improved, and by applying the cyclic nitrogen-containing polymer to the solid electrolytic capacitor, the capacitance, the reliability, the voltage resistance performance, and the thermal resistance performance of the solid electrolytic capacitor can be improved, the dissipation factor value, the 120kHz equivalent series resistor, and the service lifetime can be reduced.

The invention discloses a flexible three-dimensional porous carbon material and a preparation method and application thereof. The method adopts a commercial melamine sponge which is low in cost as a three-dimensional flexible carbon skeleton template, and coal pitch as a carbon source, and obtains the flexible three-dimensional porous carbon material which is high in conductivity and high in specific surface area in one step through a KOH activation method; and the material is simple in preparation process, low in cost and suitable for industrial application. The material serves as a super capacitor electrode material, and has larger energy density, power density and excellent cycle stability.

The invention discloses a flexible integrated supercapacitor based on a conductive polymer and an organic hydrogel, and a preparation method thereof. The flexible integrated supercapacitor is composedof the conductive polymer and the organic hydrogel. The preparation method thereof comprises the steps of: preparing a polyvinyl alcohol electrolyte organic hydrogel from polyvinyl alcohol, 3-aminophenylboronic acid, potassium chloride and an antifreezing agent at first, then, effectively compositing the conductive polymer, 3-aminophenylboronic acid and polyvinyl alcohol together by utilization of the interaction of the hydroxyl of 3-aminophenylboronic acid and hydrogen bonds between hydroxyl groups of polyvinyl alcohol, and obtaining a flexible integrated gel state supercapacitor based on the conductive polymer and the organic hydrogel in the molecular level. The flexible integrated supercapacitor still can keep better flexibility and capacitive performance in a bending condition or at low temperature of minus 15-0 DEG C; and the preparation method is simple and easy to do, environment-friendly, and suitable for industrial production.

The invention relates to a method of preparing a titania nanotube/carbon/manganese oxide composite material by using a gaseous penetration method, which relates to a composite material preparation method, and aims at solving the problems that the existing titanate nanotube is large in resistance and poor in capacitance performance. The preparation method comprises steps: 1, a titanium sheet with a polished surface is prepared; 2, the titanium sheet with a polished surface is cleaned; 3; an electrolytic reaction is carried out on the titanium sheet; 4, the titanium sheet is taken out and dried and then a titania nanotube is obtained; 5, air is exhausted; and 6, gaseous penetration is carried out, and the titania nanotube/carbon/manganese oxide composite material is obtained. The capacitance value of the obtained titania nanotube/carbon/manganese oxide composite material is nearly ten times that of the titania nanotube; the resistance of the obtained titania nanotube/carbon/manganese oxide composite material is reduced by three orders of magnitude, and conductivity is significantly improved. A titania nanotube/carbon/manganese oxide composite material preparation method can be acquired.

The invention provides a method for preparing modified activated carbon. The method comprises the steps of mixing activated carbon with water, and obtaining a mixed material; carrying out ultrasonic treatment on the mixed material; carrying out ozone oxidation treatment; freezing under -18 to -20 DEG C; carrying out freezing and drying under -18 to -20 DEG C. According to the method for preparing the modified activated carbon and the capacitive deionization electrode, provided by the invention, the used raw material is the activated carbon, the cost is low, and the activated carbon can be conveniently and easily obtained; the prepared modified activated carbon has good hydrophilia and capacitive performance through simple ozonation treatment, and the modified activated carbon is suitable for a capacitive deionization technology; the modified activated carbon is used for an electrode material of the capacitive deionization technology, the desalting quantity and the desalting speed can be effectively increased, and a good application prospect is obtained.

The invention discloses a self-supporting CoMoS<4> supercapacitor electrode material and a preparation method and application thereof. A self-supporting Co(OH)<2> electrode precursor is obtained by anelectrodeposition method; ammonium paramolybdate and ammonia water are heated to react to generate ammonium molybdate, and then (NH4)<2>S is added to react with the ammonium molybdate to form (NH4)<2>MoS<4>; precipitate of (NH4)<2>MoS<4> is dispersed uniformly in water, then the precipitate of the (NH4)<2>MoS<4> is placed in the electrode precursor for a hydrothermal reaction, and through aftertreatment, the self-supporting CoMoS<4> supercapacitor electrode material is obtained. According to the self-supporting CoMoS<4> supercapacitor electrode material and the preparation method and application thereof, costs of a binder and a conductive agent in the electrode preparation process can be eliminated, and meanwhile, the active material component ratio of pole pieces is improved, so that thespecific capacitance per unit area is improved. The self-supporting CoMoS<4> supercapacitor electrode material has a huge specific surface area and abundant micropores, and can effectively be in contact with an electrolytic solution to obtain the highly stable electrode material.

The invention discloses a preparation method of a high-specific surface area nitrogen-rich classified porous carbon electrode material for a supercapacitor. Zinc disodium EDTA is taken as the carbon source, is carbonized at the constant temperature of 700-1000 DEG C under the protection of the inert gas, and then is pickled with acid and washed with water to prepare the high-specific surface areanitrogen-rich classified porous carbon electrode material. The prepared high-specific surface area nitrogen-rich classified porous carbon electrode material has a high specific surface area (1500-2800m<2>g<-1>), has a developed classified porous structure (the pore volume is 1.2-3.6 cm<3>g<-1>), is rich in nitrogen (the nitrogen content is 1.8-12.6%), and has excellent capacitive performance andrate capability when being applied as the electrode material for the supercapacitor. The method is simple, environmentally friendly, and relatively low in cost.

Unidirectional and bi-directional low capacitance transient voltage suppressors (“TVS”) and steering diodes are disclosed. In one embodiment, the TVS comprise TVS p-n junction diode element(s), (101) low-capacitance (“LC”) PIN or NIP diode element(s) (102), the TVS p-n junction diode element(s) (101) being placed in series with and in opposite polarity to the LC PIN or NIP diodes (102). In another embodiment, the steering diode comprise only LC PIN or NIP diode(s) (402, 403) arranged as steering diodes. This circuit arrangement is operable to clamp high-voltage transients of either polarity to a predetermined level, minimizes parasitic losses and signal-line distortion, and minimize capacitance variation. The present invention is also operable to reduce the complexity of impedance matching within a high frequency circuit.

The invention discloses a preparation method of a cellulose-polyvinyl alcohol composite film based on phase inversion and a preparation method of a supercapacitor. The preparation method comprises thefollowing steps: preparing a cellulose solution from sodium hydroxide, urea and cellulose raw materials; mixing the cellulose solution and a polyvinyl alcohol solution in proportion to form a film toobtain a thin film, wherein cellulose in the thin film accounts for 10-25% of the solid content of the thin film; soaking and regenerating the film by using a mixed solution of calcium chloride and hydrochloric acid, then soaking and plasticizing the film by using glycerol, and finally drying to obtain the cellulose-polyvinyl alcohol composite film. The cellulose and -polyvinyl alcohol compositefilm is prepared by taking cellulose as a raw material and sodium hydroxide, urea and water as solvents and adopting a dissolution-regeneration and phase inversion method. Compared with a traditionalpolyolefin material, the composite film has the advantages of good tensile strength, elongation at break and lyophilicity and high porosity, liquid absorption rate and liquid retention rate. The supercapacitor assembled by the composite film can show good electrochemical performance.

The invention discloses a flexible composite thin film material and a preparation method thereof. The flexible composite thin film material is of a sandwich structure (graphene-polypyrrole-nano-porousgold). A thin film comprises a structural unit of the composite thin film material; and the structural unit of the composite thin film material comprises a nano-porous gold thin film layer, a polypyrrole layer, nano-gold particles embedded into the polypyrrole layer and a graphene layer. The preparation method comprises the steps that firstly, a nano-porous gold thin film is prepared; secondly, apolypyrrole/nano-porous gold composite thin film is prepared; thirdly, a nano-porous gold thin film with the embedded nano-gold particles is prepared; and fourthly, a graphene thin film is prepared.The prepared flexible composite thin film material of the sandwich structure (graphene-polypyrrole-nano-porous gold) has a large specific surface area and high electrical conductivity; and by using the method of compositing pyrrole and graphene with good electrical conduction properties and a large specific surface area, the electrical conductivity of polypyrrole is obviously increased.

Te invention discloses a three-dimensional nano bead curtain shaped composite metal nitride/oxide, which is prepared by adopting a method of growing a composite metal oxide precursor at the surface bytaking a conductive support material as an electrode and a support and then forming a composite metal nitride/oxide loaded on the conductive support material through heat treatment and nitridation. The composite metal nitride/oxide is that composite metal nitride nanoparticles connected by composite metal oxide nanosheets form a three-dimensional nano bead curtain shape on the conductive supportmaterial, wherein the size of the composite metal oxide nanosheets is 100-500nm, the diameter of the composite metal nitride nanoparticles is 5-50nm, and the loading capacity of the composite metal nitride/oxide on the conductive support is 0.1-0.5mg/cm<2>. The operation process is simple, the low cost and the high capacitive performance enable the combination of the composite metal nitride/oxideto have wide application prospects in the aspect of energy storage.

Disclosed is an electrochemical capacitor which contains titanium dioxide. A negative plate is made from active carbon, conductive agent and caking agent at weight ratio of 75-85:15-10:10-5, and a positive plate is made from titanium dioxide dopant material, conductive agent and caking agent at weight ratio of 75-85:15-10:10-5. The method for fabricating the electrochemical capacitor which contains titanium dioxide includes the following steps: getting the following materials according to weight proportions: titanium dioxide 100, compound doped with metal 1-10, and graphite 1-10; mixing the titanium dioxide and the compound doped with metal and then baking the mixture in a muffle furnace and at last mixing the baked mixture with the graphite, thus obtaining titanium dioxide dopant material; making the titanium dioxide dopant material, the conductive agent and the caking agent at weight ratio of 75-85:15-10:10-5 into a positive plate for the electrochemical capacitor. The capacitor fabricated through the method is used on electric tools and electric automobiles and can reduce pollution to the environment.