142results about How to "Good capacitance characteristics" patented technology

The invention discloses a method for preparing electrodes of a dissymmetric super capacitor based on nickel foam. The method comprises the steps: washing the nickel foam, soaking the nickel foam into a graphene oxide aqueous solution to obtain nickel foam in which graphene oxide deposits, serving the nickel foam in which the graphene oxide deposits as precursor materials, and respectively adopting a three-electrode method for preparaing a positive electrode and a negative electrode of the dissymmetric super capacitor, wherein the positive electrode is composed of composite materials of graphene, a carbon nanometer tube and the nickel foam, and the negative electrode is composed of composite materials of graphene, manganese dioxide and the nickel foam. The invention further discloses some other methods for preparing the electrodes of the super capacitor based on the similar principle, and products which correspond to the methods. By means of the methods and the products, respective high-ratio capacitance characteristics of the composite materials are fully played, and energy density of the super capacitor is improved. In addition, usage of various combined reagents can be avoided, and accordingly large-batch industrial production is conducted in a mode of convenient control, low cost and low energy consumption.

The invention discloses a method for preparing a porous (micro-porous and mesoporous) carbon micron tube from catkin, poplar seed or phoenix tree seed as a raw material. According to the method disclosed by the invention, the porous carbon micron tube can be prepared from natural biomasses such as the poplar seed, the catkin or the phoenix tree seed by using a chemical activation method, a physical activation method and a chemical and physical activation method under different conditions. The method disclosed by the invention has the characteristics of simple process, low cost, environment friendliness and the like. The specific surface area of the obtained micro-porous carbon micron tube can reach 1000-2000m<2>/g and the specific surface area of the obtained mesoporous) carbon micron tube can reach 500-1000m<2>/g. The porous carbon micron tube obtained by the method disclosed by the invention has the advantages of large specific surface area, developed porous structure, favorable catalytic oxygen reduction performance and favorable capacitance characteristic and can be used as an electrode material of a supercapacitor and a fuel cell.

A transition metal/carbon nanotube composite includes a carbon nanotube and a transition metal oxide coating layer disposed on the carbon nanotube. The transition metal oxide coating layer includes a nickel-cobalt oxide

The present invention relates to a high frequency module board device having a high frequency transmitting and receiving circuit for modulating and demodulating a high frequency signal. The high frequency module board device comprises a base board (2) whose main surface is formed as a build-up surface (2a) and a high frequency circuit part (3) formed on the build-up surface of the base board (2) and having passive elements formed. The base board (2) has an area (29) in which wiring is not formed in a lower layer from a fourth wiring layer (8b). The high frequency circuit part (3) has an upper electrode part (36) and a lower electrode part (35) in positions corresponding to the area (29) in which the wiring is not formed. Thus, since a capacitance (18) is provided just above the area (29) in which the wiring is not formed, a parasitic capacity that the capacitance (18) receives from ground patterns (14) is reduced. Accordingly, the characteristics of the capacitance (18) can be improved.

The dielectric ceramic has a composition represented by general formula 100(Ba_1-x-ySr_xCa_y)_m(Ti_1-zZr_z)O₃+aBaO+bR₂O₃+cMgO+dMnO+eCuO+fV₂O₅+gX_uO_v (where R is a rare-earth element such as La, Ce or Pr; and X_uO_v is an oxide group including at least Si); and 0≦x≦0.05, 0≦y≦0.08 (preferably 0.02≦y≦0.08), 0≦z≦0.05, 0.990≦m, 100.2≦(100 m+a)≦102, 0.05≦b≦0.5, 0.05≦c≦2, 0.05≦d≦1.3, 0.1≦e≦1.0, 0.02≦f≦0.15, and 0.2≦g≦2. With this composition, a monolithic ceramic capacitor retaining good dielectric characteristics and temperature characteristics even if a high field strength voltage is applied by further thinning the dielectric layers thereof and having excellent reliability achieving good isolating property, dielectric strength, and high-temperature load life is obtained.

A dynamic random access memory (DRAM) and a manufacturing method thereof are disclosed. A storage cell of the DRAM includes a FINFET and a capacitor. A gate of the FINFET is formed by a metal nitride or a carbonized metal having the effect of stress-induced strain. A gate dielectric of the FINFET and/or a dielectric of the capacitor can be formed by a ferroelectric material having negative capacitance characteristics. A strained-gate engineering is used in the invention achieve effects of (1) increasing ferro-electricity of the dielectric to enhance the operation speed and endurance of the FINFET; and (2) enhancing the ferro negative capacitance effect to improve the sub-threshold swing of the FINFET, so that the switching power and the off-current of the FINFET can be reduced and the charge retention capability of capacitor can be effectively enhanced to improve the operation characteristics of the DRAM.

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.

A semiconductor capacitor structure includes a first metal layer, a second metal layer, a first set of via plugs, a second set of via plugs, and a dielectric layer. The first metal layer includes a first portion, a plurality of parallel-arranged second portions, a third portion, and a plurality of parallel-arranged fourth portions. The second metal layer includes a fifth section, a plurality of sixth sections, a seventh section, and a plurality of eighth sections. The first set of via plugs electrically connects the plurality of second sections to the plurality of sixth sections. The second set of via plugs electrically connects the plurality of fourth sections to the plurality of eighth sections.

The invention provides a self-supporting type nano-porous nickel/nickel oxide combined electrode plate and a preparation method thereof. The electrode plate is composed of a current collector and active substance, the current collector is composed of a nickel-based amorphous alloy base body and nano-porous nickel, and the active substance is nano nickel oxide which grows on the surface of the nano-porous nickel. The cross section of the electrode plate comprises three layers, the middle core layer is the nickel-based amorphous alloy base body, the surfaces of the two sides of the middle core layer are covered by combined electrode material layers composed of nano-porous nickel and nano nickel oxide, the thickness of the electrode plate is 25-35 micrometers, the thickness of each nano-porous nickel/nickel oxide combined electrode material layer is 2.1-3.5 micrometers, and the nickel-based amorphous alloy is composed of Ni40 + x (Ti0.35 Zr0.45 Al0.20) 60 - x (x=0-5). The effective specific area of active substance NiO is improved, the actual capacitance characteristic, which can be given to play in a super capacitor, of nickel oxide is improved, and the specific capacitance of the combined electrode plate can reach up to 847.9 F/cm<3>.

An electrical double-layer capacitor electrode with excellent capacitance characteristics is obtained together with a manufacturing method therefor.

Paper-molded sheet 2 of carbon nanotubes is integrated with etched foil 1 constituting a collector, by means of bumps and indentations 1a formed on the surface of etched foil 1 to prepare an electrical double-layer capacitor electrode. Alternatively, carbon nanotubes 4 grown around core catalyst particles on substrate 3 are integrated with etched foil 1 by means of bumps and indentations 1a formed on the surface of etched foil 1 to prepare an electrical double-layer capacitor electrode. To manufacture these electrodes, this carbon nanotube sheet 2 or substrate 3 with carbon nanotubes grown thereon is laid over bumps and indentations la on the surface of etched foil 1, and the sheet or substrate and the foil are pressed under 0.01 to 100 t/cm² of pressure to integrate the carbon nanotubes with the etched foil.

The invention relates to a modified carbon material and a preparation method thereof, cathode lead paste, a polar plate and a lead carbon battery. The preparation method comprises the steps of 1 crushing biologic material, wherein the biologic material is one or more of starch, lignin, corn cores, rice hull, ears, trees, shells, coconut shells, leaves and straw; 2, processing the crushed biologic material by inorganic strong acid and/or inorganic strong base solution, filtering and thereby obtaining a precursor; 3, placing the precursor into aqueous solution comprising high hydrogen evolution overpotential metal salt, dispersing by supersonic vibration and stirring for a period, filter, cleaning and thereby obtaining the modified precursor; and 4, processing the modified precursor to obtain the modified carbon material. According to the preparation method, the modified carbon material with uniform distribution and good combinability is prepared, the hydrogen evolution overpotential of the carbon material is improved, the high-power charging and discharging performance of the lead carbon battery is enhanced, and the life of the battery is prolonged.

The invention discloses a method for producing porous carbon for a super capacitor by utilizing a lignosulfonate. The method is characterized by comprising the following steps of: putting calcium lignosulphonate or magnesium lignosulphonate in nitrogen or argon atmosphere and keeping at 600-800 DEG C for 1-4 hours; after cooling to the room temperature, soaking calcium lignosulphonate or magnesium lignosulphonate in diluted hydrochloric acid or diluted nitric acid having a mass concentration of 10-30%, carrying out ultrasonic dispersion to even distribution and then stirring for not less than 6 hours; next, performing suction filtering and water washing until the eluate is neutral, and then drying, thereby obtaining porous carbon material suitable for manufacturing the super capacitor. The preparation method disclosed by the invention is simple and convenient for operation; and the obtained porous carbon material can be used for preparing the super capacitor which is capable of showing excellent capacitance characteristics.

The present invention discloses a preparation method of a surface-modified manganese dioxide (MnO2) product loaded by an N-doped hollow carbon sphere (N-HCS). The method comprises the following stepsof: (1) preparing a hollow carbon sphere (HCS); (2) preparing a polydopamine-modified hollow carbon sphere (PDA-HCS); (3) preparing a graphene-modified N-doped hollow carbon sphere (N-HCS@Gr); (4) preparing a polyaniline-modified N-HCS@Gr (N-HCS@Gr@PANI); and (5) preparing a surface-modified MnO2 product loaded by an N-doped hollow carbon sphere (N-HCS@Gr@PANI@MnO2). The N-HCS@Gr@PANI@MnO2 productfully combines excellent performances of the N-doped hollow carbon sphere, a large superficial area and an excellent conductivity of graphene, reductibility and conductivity of the PANI and excellentcapacitance characteristics of the MnO2 itself, and therefore, the N-HCS@Gr@PANI@MnO2 product expresses very high specific capacitance and is electrode material of a super electrochemical capacitor with a wide application prospect.

A method of synthesizing mechanically resilient titanium carbide (TiC) nano-fibrous felts comprising continuous nanofibers or nano-ribbons with TiC crystallites embedded in carbon matrix, comprising: (a) electrospinning a spin dope for making precursor nanofibers with diameters less than 0.5 μm; (b) overlaying the nanofibers to produce a nano-fibrous mat (felt); and then (c) heating the nano-felts first at a low temperature, and then at a high temperature for making electrospun continuous nanofibers or nano-ribbons with TiC crystallites embedded in carbon matrix; and (d) chlorinating the above electrospun nano-felts at an elevated temperature to remove titanium for producing carbon-derived-carbon (CDC) nano-fibrous felt with high specific surface areas.

The invention provides a method for preparing a cobaltous oxide/graphene nanometer composite material, which comprises the steps of performing ultrasonic processing on graphite oxide in deionized water for obtaining graphene oxide solution, dissolving Co(NO3)2.6H2O into the deionized water for obtaining cobaltous nitrate solution, then dripping NH3.H2O, dispersing a generated solid product in the deionized water for preparing cobalt hydroxide colloidal solution; mixing the cobaltous nitrate solution with the cobalt hydroxide colloidal solution, performing washing and drying; and processing at the temperature of 150-500 DEG C for obtaining the cobaltous oxide/graphene nanometer composite material. The method for preparing the cobaltous oxide/graphene nanometer composite material has advantages of simple operation, high speed, large-scale production, and environment-friendly effect.

A highly reliable ceramic electronic device having an excellent temperature characteristic of a capacitance and a low IR temperature dependency, comprising a dielectric layer: wherein the dielectric layer includes a main component expressed by a composition formula of Ba_mTiO_2+m, wherein “m” satisfies 0.995≦m≦1.010 and a ratio of Ba and Ti satisfies 0.995≦Ba/Ti≦1.010, and, as subcomponents, an oxide of Al and an oxide of Si or an oxide of R (note that R is at least one kind selected from Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu); and includes a secondary phase composed of at least a part of the oxide of Al and at least a part of the oxide of Si or the oxide of R and being different from a main phase mainly composed of the main component; and the production method are provided.