85results about How to "Optimize electronic structure" patented technology

The invention discloses an oxygen reduction and oxygen evolution Co2P@NPC double-function compound catalyst and a preparation method and application thereof. The compound catalyst comprises N-P-codoped carbon layer coated Co2P nano rods and/or nano particles. The preparation method includes: evaporating and drying the solution of cobalt acetate, concentrated phosphoric acid and urea, and performing high-temperature treatment under protective atmosphere to obtain the compound catalyst. The preparation method has the advantages that the method is simple, low in cost and beneficial to industrial production; the prepared oxygen reduction and oxygen evolution Co2P@NPC double-function compound catalyst is applicable to fuel cell and water decomposition, high in activity and good in stability, the catalytic performance of the compound catalyst is close to that of a commercial precious metal 20wt% Pt/C and RuO2 catalyst, and the compound catalyst is promising in application prospect.

The invention discloses a Pd nano-particle loaded ferronickel double hydroxide nanosheet array structure material, a preparation method and application thereof. The preparation method comprises the following steps: adding nickel salt, ferric salt, urea and quaternary ammonium salt into absolute methanol, ultrasonically dissolving the components, adding a palladium source solution, uniformly mixingthe components, transferring the mixed solution into a reaction kettle, obliquely placing foamed nickel into the mixed solution, carrying out solvothermal reaction, naturally cooling the reaction product to room temperature, and washing and drying the reaction product to obtain the Pd nanoparticle loaded NiFe LDH nanosheet array structure material. The material has the advantages of high activity, good durability, simple preparation process and low cost in alkaline electrolyte, shows excellent activity and stability for oxygen evolution reaction, hydrogen evolution reaction and total hydrolysis reaction, and has very high value in practical application of electro-catalytic water decomposition materials.

The invention provides a molecular imprinting catalytic membrane capable of selectively degrading ciprofloxacin and a preparation method. The preparation method comprises the following steps: step 1, preparing graphite-like nitrogen carbonate g-C3N4; step 2, preparing a noble metal loaded semiconductor composite material; and step 3, preparing the molecular imprinting catalytic membrane capable of selectively degrading the ciprofloxacin. The material prepared by the preparation method can effectively realize the aims of preferably selectively adsorbing and degrading target pollutants in a mixed sewage system; post-treatment is simple, a photocatalyst is conveniently recycled for a plurality of times and secondary pollution is effectively avoided; and the molecular imprinting catalytic membrane has the advantage of selectively treating antibiotic wastewater very well.

The invention relates to a preparation method for a cobalt-nickel bimetal metaphosphate nanometer array loaded on a carbon cloth substrate, and relates to the field of preparation methods for bimetalmetaphosphate modified carbon nanometer composite materials. The invention is to solve the technical problems of low stability and catalytic activity for a conventional anode catalyst and high cost for noble metals and oxides of the noble metals. The preparation method comprises the following steps: allowing Co-based bimetallic MOFs to uniformly grow on a conductive carbon cloth through a co-precipitation method so as to obtain a CoNi(n)-ZIF nanometer array, and subjecting the CoNi(n)-ZIF nanometer array to a low-temperature solid-phase phosphorylation reaction so as to obtain a Co<2-x>NixP4O<12->C nanometer array catalyst. The catalyst provided by the invention is a non-noble metal catalyst, reduces the cost of a reaction and has good catalytic activity to oxygen evolution. The material prepared by using the method provided by the invention is used in an oxygen evolution reaction through water electrolysis.

The invention provides a noble metal supported nano frame catalyst and a preparation method and application thereof. The catalyst comprises noble metals and transition metal hydroxides, and is of a hollow nano frame structure. According to the noble metal supported nano frame catalyst, the catalyst is of a hollow nano frame structure, so that the activation specific surface area is large, the wallthickness is small, and the substance transmission distance is short; the catalyst supports a nickel cobalt hydroxide with the noble metals, so that the electronic structure between the nickel cobalthydroxide and the noble metals is optimized, the stability of the catalyst is high; the overpotential of catalyzing a hydrogen evolution reaction can be effectively reduced, wherein the overpotentialis only 60 mV when the current density is 10 mA cm-2; and the catalyst is simple in preparation method, short in production cycle, and wide in application prospect.

A light emission device including an electron discharger including a first substrate, a plurality of cathode electrodes, a plurality of electron emission regions, and a plurality of gate electrodes, the first substrate having a plurality of recessed portions at a first surface of the first substrate, the cathode electrodes extending along a first direction and in the recessed portions, the electron emission regions on the cathode electrodes, and the gate electrodes extending along a second direction crossing the first direction; a light emitter including a second substrate, the second substrate having a second surface facing the first surface of the first substrate with a gap therebetween; and a plurality of fixing blocks on the first substrate and between the gate electrodes, the fixing blocks being separated from the light emitter.

The invention relates to a preparation method and application of NiFe-LDH oxygen evolution electrocatalytic material rich in cation vacancy. The preparation method includes the steps of (1) soaking Ni-Fe alloy matrix in electrolyte which contains, by weight, 1-3% of NaF, 4-7% of (NH4)2MoO4, 15-25% of H2O, 25-40% of glycerol and 25-55% of phosphoric acid; (2) subjecting the Ni-Fe alloy matrix soaked in the electrolyte to anodizing to obtain NiFeMo anodized film; (3) subjecting a sample treated in step (2) to alkaline liquid etching, washing, and drying to obtain the NiFe-LDH oxygen evolution electrocatalytic material. The NiFe-LDH oxygen evolution electrocatalytic material prepared herein has high catalytic activity and good electrochemical stability; the preparation method is simple, efficient and low in cost, is well popularizable and helps further promote the development and application of LDH catalysts.

The invention provides a catalyst, and a preparation method and an application thereof. The catalyst comprises an active component, a carrier and an auxiliary agent, wherein the active component is one or two selected from the group consisting of nickel and ruthenium; the carrier is potassium titanate; and the auxiliary agent is rare earth oxide. The catalyst has the following advantages: the potassium titanate is adopted as the carrier, and potassium ions are highly dispersed in the structure of titanium dioxide, so the performances of the potassium titanate used as a cocatalyst are easily and greatly improved; meanwhile, the potassium titanate has large specific surface area and facilitates dispersion of the active component, so the catalyst has high low-temperature catalytic activity and good ammonia decomposition catalytic effect.

The invention relates to a conductive agent for a negative electrode of a lithium ion battery and a preparation method for the battery containing the conductive agent. Silicon quantum dots SiQDs are mixed into micropores of carbon nanofibers CNFs by adopting an electrospinning technology, and a compound SiQDs/CNFs of the silicon quantum dots/carbon nanofibers is synthesized, and then the compoundSiQDs/CNFs is used as the conductive agent for the negative electrode of the lithium ion battery. The silicon quantum dots prepared in the method have a very small size, an effect of buffering the volume expansion of silicon particles can be effectively achieved by the micropore structures of the carbon nanofibers in a circulation process, the damage of the volume expansion of silicon in a lithiumintercalation process to an electrode structure is solved, and meanwhile, through the porous structures in the carbon nanofibers, a diffusion path of lithium ions can be greatly shortened, the diffusion speed of the lithium ions is increased, and solid-phase diffusion is improved. The battery designed by the composite conductive agent prepared by the method has a great improvement in the aspectsof the energy density, the power density and the cycling performance.

The invention belongs to the field of energy materials and electrochemical catalysis and energy storage, and aims to provide a boron-nitrogen-phosphorus ternary doped metal-free carbon material as well as a preparation method and application thereof. The boron-nitrogen-phosphorus ternary doped metal-free carbon material is obtained by taking a phenolic aromatic hydrocarbon compound or a derivativethereof as a carbon source, a phosphorus-containing organic matter or inorganic matter as a phosphorus source, a nitrogen-containing organic matter as a nitrogen source and a boron-containing organicmatter or inorganic matter as a boron source; after sufficient polymerization by a solvothermal method, oxidizing at a low temperature of 100-350 DEG C, and roasting at a high temperature of 600-1200DEG C under the protection of N2 atmosphere. The carbon material is wide in raw material source, and the preparation method is mature in process, is simple to operate, and is convenient for the large-scale production.

The invention discloses a preparation method of a boron-doped porous carbon material. The preparation method comprises the following steps: (1) preparing a mixed solution; (2) preparing polyamide acid(PAA)/boric acid composite film; (3) preparing polyimide (PI)/boric acid composite film; and (4) preparing the boron-doped porous carbon material. The porous carbon material can be directly used forpreparing the high-performance miniature super-capacitor. The method is fast and simple and low in cost, the prepared porous carbon material is high in specific area, adjustable in aperture distribution and good in conductivity, the porous carbon material can be directly patterned and a certain amount of boron is doped, and the porous carbon material can be used for preparing the high-performanceminiature super-capacitor.

A light emission device for simplifying a structure of an electron emission unit and a manufacturing process thereof is provided. A display device using the light emission device as a light source is also provided. The light emission device includes a vacuum panel having a first substrate and a second substrate facing each other. A sealing member is between the first and second substrates. Recesss portions each have a depth into a side of the first substrate facing the second substrate. Cathode electrodes are in corresponding recesses. Electron emission regions are on corresponding cathode electrodes. A gate electrode is fixed at one side of the first substrate at a distance from the electron emission regions. A light emission unit is at one side of the second substrate. The gate electrode includes a mesh unit having openings for passing through an electron beam and a supporting member surrounding the mesh unit.

The invention discloses LiFePO4 crystallite coated with nano metal oxide and a preparation method thereof. The LiFePO4 crystallite coated with nano metal oxide is prepared from, by mass, 90-97% of LiFePO4 and 3-10% of nano-MxOy mixture, wherein M is one or more of Mg, Al, Ti, Zr, Cu, Sn and Ca, and the nano-MxOy mixture is one or more of MgO, Al2O3, TiO2, ZrO2, CuO, SnO2 and CaO. According to theLiFePO4 crystallite coated with nano metal oxide, through the compound effect of the materials, on the one hand, the charge transfer resistance can be effectively reduced, on the other hand, the direct contact between an electrolyte solution and the electrode material can be reduced, side reactions between the electrolyte solution and the electrode material are avoided, and therefore the rate performance and cycle performance of the material are significantly improved.

The invention provides an IrFe nano alloy composite material. The IrFe nano alloy composite material comprises an N-doped carbon layer and an IrFe nano alloy compounded on the N-doped carbon layer. The nitrogen-doped carbon layer supported IrFe nano alloy composite material is obtained by supporting a noble metal iridium-modified iron-based metal organic complex which is used as a precursor on a N-doped carbon layer. The method provided by the invention utilizes alloying of a transition metal and a noble metal to regulate and control catalytic performance, and alloying can generate a good electronic structure, thereby effectively promoting improvement of the catalytic performance; the nitrogen-doped carbon layer supported IrFe nano alloy composite material is constructed to reduce the useamount of the noble metal, the method reduces the use amount of the noble metal while improving the performance of the catalyst, and the catalyst has good electrocatalysis practical prospects; and inaddition, the preparation method has a simple step, convenient operation and mild conditions, is suitable for promotion and application, and has the good electrocatalysis practical prospects.

The invention provides a preparation method of a nanoscale ruthenium dioxide-coated ruthenium-loaded carbon micron sheet. Compared with the prior art, the preparation method of the nano-scale ruthenium dioxide coated ruthenium-loaded carbon micron sheet has the advantages that the nano-scale ruthenium dioxide coated ruthenium-loaded carbon micron sheet prepared by the preparation method has the characteristics of high loading capacity and high dispersion and has a large specific surface area and a large number of mesoporous structures; the micro ruthenium dioxide coated ruthenium nanoparticles and carbon are chemically coupled together, so that the conductivity of the material is improved; the electronic structure of the material is improved and the number of active sites is increased by increasing the loading capacity of the ruthenium dioxide coated ruthenium nanoparticles; meanwhile, due to the large specific surface area and a large number of mesoporous structures, electrolyte permeation and gas release are facilitated, and the electro-catalytic activity and stability of the material are synergistically improved; and the preparation method is simple, consists of simple adsorption, calcination and oxidation, is high in operability, easy to repeat, high in stability and easy for large-scale production, and can meet the actual requirement of hydrogen production by fully decomposing water.

The invention discloses a microcrystal LiVOPO4-LiMPO4-TiO2 composite lithium battery material and the preparation method thereof, belonging to the technical field of the preparation of lithium battery materials. According to the invention, the LiVOPO4 glass ceramics (71 to 93% by weight), LiMPO4 (5% to 20%) and nanometer TiO2 (2% to 9%) are used as the raw materials to prepare the LiVOPO4 glass ceramics-LiMPO4-nanometer TiO2 composite lithium battery material by means of the high temperature solid phase synthesis method. According to the invention, through the nano-composite interaction of the materials, the charge transfer impedance can be effectively reduced on the one hand, and the direct contact between the electrolyte solution and the electrode material can be reduced on the other hand, and the side reaction between the electrolyte solution and the electrode material can be avoided, therefore, the rate performance and cycle performance of the material can be remarkably improved. The product of the invention can be used as a cathode material of a lithium ion secondary battery used in a portable electronic device and an electric automobile.

The invention discloses a PtAg nanocrystal with a porous double hollow sphere structure, a preparation method thereof, and application of the material as a methanol oxidation anode catalyst. The preparation method comprises the following steps: taking Pt salt and Ag salt as metal precursors, taking N'N-methylenebisacrylamide as a structure-directing agent, adding a reducing agent and performing aone-step hydrothermal reaction to obtain the PtAg nanocrystals. The method of the invention has mild conditions and high yield, is green and pollution-free, and is suitable for commercial production.As a methanol oxidation anode catalyst, the obtained porous double hollow sphere PtAg nanocrystals have the advantages of excellent electrocatalytic activity, stability and the like.

The invention relates to a preparation method and application of a porous carbon coated PdFe/C alloy nano-frame. According to the preparation method, 1-naphthylamine (C10H9N), adopted as a coordination agent, forms a Pd(II)-(C10H7-NH2) flaky yellow precipitate complex with PdCl2; the Pd(II)-(C10H7-NH2) flaky yellow precipitate complex is arranged in an aqueous solution of FeCl3 so as to be subjected to ultrasonic mixing; an obtained mixture is stirred for a long time, so that Fe<3+> can be fully adsorbed on the surface of the flaky precipitate, and an obtained Pd(II)/Fe(III)-(C10H7-NH2) flakyyellow-green precipitate is arranged in an inert atmosphere so as to be subjected to high-temperature heat treatment, so that the porous carbon coated PdFe/C alloy nano-frame can be obtained. The porous carbon coated PdFe/C alloy nano-frame prepared by the method has the advantages of ultrafine particle size of PdFe alloy, adjustable compositions, high electrochemical activity, high stability, simple preparation process, convenience in batch production, environmental friendliness and the like. The porous carbon coated PdFe/C alloy nano-frame shows higher electrocatalytic activity and stabilitywhen being used as a cathode oxygen reduction catalyst under an acidic condition.

The invention discloses a preparation method of a transition metal doped nickel-based metal organic framework three-dimensional electrode material. The preparation method comprises the following stepsof: (1) preparing a three-dimensional conductive graphite substrate from a graphite flake by an electrochemical stripping method; and (2) putting the material obtained in the step (1) into a mixed solution of a bivalent nickel salt, a doped transition metal salt and terephthalic acid, and carrying out a one-step hydrothermal reaction so as to grow and load a transition metal doped nickel-based metal organic framework nanosheet array on a three-dimensional conductive graphite substrate in situ, thus obtaining the transition metal doped nickel-based metal organic framework three-dimensional electrode material. The invention further provides the transition metal doped nickel-based metal organic framework three-dimensional electrode material obtained through the preparation method and application of the transition metal doped nickel-based metal organic framework three-dimensional electrode material to water electrolysis and oxygen evolution in alkaline electrolyte. The three-dimensional electrode material shows excellent catalytic performance in alkaline electrolyte, has good stability, and has high practical value and prospect in industrial application.

The invention provides an alloy nanocage catalyst and a preparation method and application thereof. The catalyst contains an alloy of noble metal and non-noble metal. The catalyst is shaped as a flower-like hollow nanocage structure. According to the catalyst, non-noble metal partially replaces noble metal to form the alloy, the two metals have synergistic effect, the electronic structure is optimized, and catalyst stability is enhanced. The catalyst has an octahedron angle etched hollow structure. The structure is stable, and specific surface area is large. Meanwhile, application amount of noble metal is low, and catalyst cost is low. The catalyst is applied to direct methanol fuel cells, and catalytic activity for methanol oxidation can reach 800 A/g and above.

The invention provides a preparation method of a cobalt and nickel dual-doped tin sulfide nanosheet. The method comprises the steps that 1, a tin source, a nickel source, a cobalt source, a sulfur source and a ligand are subjected to a mixed reaction, and a cobalt and nickel dual-doped tin precursor is obtained; 2, the cobalt and nickel dual-doped tin precursor, oleylamine and solvents are mixed,heated and cooled to obtain the cobalt and nickel dual-doped tin sulfide nanosheet. By introducing cobalt and nickel ions through the nickel source and the cobalt source, the electronic structure of the metal sulfide catalyst is improved, and therefore the catalytic activity and selectivity of the obtained cobalt and nickel dual-doped tin sulfide nanosheet for the carbon dioxide electrocatalytic reduction reaction are improved. The cobalt and nickel dual-doped tin sulfide nanosheet obtained through the preparation method is high in catalytic activity, good in stability and high in selectivity.