8 results about "Bi element" patented technology

The application discloses a kind of Bi / OVs-Bi2WO6-Cl catalysts with multiple active sites synergy and a preparation method and application thereof, and belongs to the field of photocatalysis technology, the application uses hydrothermal method to dope Cl into Bi2WO6, then in-situ reduction is generated by using chemical reduction method Bi element and oxygen vacancy, the introduction of multiple active sites, on the one hand, promote the effective separation of photoinduced electron-hole pairs, fully play the catalytic performance of semiconductor, on the other hand, can provide more CO2 activation site, finally make Bi / OVs-Bi2WO6-Cl photocatalyst have better CO2 reduction performance;The material has high photocatalytic selectivity, and the production cost is low, and the production process is simple.

The invention discloses a novel thermoelectric material based on N-type BiSbSe3 polycrystal and a preparation method thereof, and belongs to the technical field of thermoelectric material preparation, the thermoelectric material is S solid solution and halogen doped N-type BiSbSe3 polycrystal, the chemical general formula of the thermoelectric material is BiSbSe3-x-y SxMy, M is one of Br, Cl and I, the molar ratio of Bi to Sb to Se to S to M is 1: 1: 3-x-y: x: y, x is greater than or equal to 0.12 and less than or equal to 0.48, and y is greater than or equal to 0 and less than or equal to 0.06. The preparation method comprises the following steps: (1) weighing required raw materials including a Bi elementary substance, a Sb elementary substance, a Se elementary substance, Bi2S3 and a halogen introducing substance, ensuring that the molar ratio of Bi to Sb to Se to S to M is 1: 1: (3-x-y): x: y, M is Br or Cl or I, x is more than or equal to 0.12 and less than or equal to 0.48, y is more than or equal to 0 and less than or equal to 0.06, and mixing the raw materials after weighing; and (2) carrying out high-temperature melting synthesis reaction on the mixed raw materials, and cooling along with a furnace after the reaction is finished, so as to finally obtain the N-type BiSbSe3 polycrystal. The problems that in the prior art, when BiSbSe3 is prepared, a quenching technology is needed for assistance, energy consumption is large, time is long, and part of media are low in safety and not environmentally friendly are solved.

The invention discloses a preparation method for obtaining an oxygen vacancy-rich Bi2WO6 material through alkali treatment and application of the oxygen vacancy-rich Bi2WO6 material in electro-catalytic nitrogen reduction. According to the invention, Bi2WO6 is prepared by adopting a hydrothermal method, and then a low-concentration NaOH solution is used for etching to obtain the Bi2WO6 material with rich oxygen vacancies. Rich oxygen vacancies are introduced into Bi2WO6, and the oxygen vacancies can be used as excellent charge carriers and reaction active sites, so that the charge transfer rate between a catalyst and N2 is promoted, and the adsorption and activation capability on N2 is improved, thereby improving the activity of catalyzing NRR. The alkali etching treatment improves the Bi element content in Bi2WO6 at the same time, and is beneficial to inhibition of hydrogen evolution side reaction, thereby improving the selectivity of the catalyst to NRR. The prepared Bi2WO6 material with rich oxygen vacancies has relatively high ammonia yield and Faraday efficiency when being applied to an electro-catalytic nitrogen reduction process, and shows good stability.

The invention provides a Bi-based material for X-ray detection and protection and a preparation method and application thereof, and belongs to the technical field of X-ray detection and protection. According to the invention, the Bi-based material is BiO (IO3), BiVO4 or Bi2WO6; the preparation method comprises the following steps: mixing an I2O5 solution and a BiH10N3O14 suspension, and reacting to obtain BiO (IO3); the preparation method comprises the following steps: mixing Bi (NO3) 3.5 H2O, NH4VO3 and a nitric acid solution, and dropwise adding ammonia water into the mixed solution until yellow precipitate appears, so as to obtain BiVO4; the preparation method comprises the following steps: mixing a Na2WO4. 2H2O solution and a Bi (NO3). 5H2O suspension, and reacting to obtain Bi2WO6. The Bi-based material disclosed by the invention has excellent X-ray detection performance and protection effect, and due to the extremely high atomic number of the Bi element, the high equivalent atomic number and density of the material are finally formed, so that full absorption of X-rays is realized.

This invention discloses a bismuth tantalum halide oxide synergistically modified with elemental Bi and oxygen vacancies, its preparation method, and its application, belonging to the field of photocatalysis technology. This invention synthesizes a Bi4TaO8Cl photocatalyst synergistically modified with elemental Bi and oxygen vacancies. By utilizing the SPR effect of bismuth metal, the absorption of visible light by Bi4TaO8Cl is enhanced, forming more active free radicals. At the same time, the synergistic modification of the photocatalyst by oxygen vacancies is effectively utilized to improve the carrier separation efficiency, further enhancing the photocatalytic degradation of NO by pure Bi4TaO8Cl.

This invention provides a high-temperature stable pulse energy storage ceramic composition and its preparation method, relating to the field of pulse energy storage ceramic materials technology. The ceramic composition is based on Ba(Zr) x Ti 1‑x The main component is a perovskite compound (Bi2O3). In addition, it contains Bi as a first secondary component (Bi element) in the form of a composite of Bi2O3 and Bi2O3·nTiO2, as well as Ca, Sr, Mg, Mn, and Si elements. Its temperature coefficient of dielectric constant (TCC) meets -750±120ppm / ℃ over a wide temperature range of -55℃ to 125℃. The ceramic composition of this invention possesses high dielectric constant, low dielectric loss, high breakdown field strength, and a fine-grained structure, making it suitable for high-reliability pulse power capacitors.

The application provides a lead-based catalyst regulated by cobalt-bismuth bimetal, a preparation method and application thereof. The catalyst comprises a carrier, and a catalytic material composed of cobalt-doped lead oxide and bismuth oxide is loaded on the surface of the carrier, and the chemical composition of the catalytic material is expressed as Co x Bi y Pb m O n The preparation method of the catalyst comprises the following steps: taking lead salt, cobalt salt and bismuth salt as metal precursors, taking boric acid as a buffer, taking trisodium citrate dihydrate as a complexing agent, and adopting a two-step electrodeposition method to prepare the catalyst. The catalyst can be used for synthesizing sodium borohydride by an electrocatalytic method. In the application, Pb elements are used as main components of electrode materials, a small amount of Co elements and Bi elements are added as additives, and under the joint action of the two additives, the efficiency of the electro-reduction reaction can be effectively improved, and the yield of sodium borohydride is improved.

The application discloses a Bi-guided controllable flower-shaped heterojunction photocatalyst and a preparation method thereof. By using a double bismuth source and a reducing agent, Bi element is introduced to control Bi2O2CO3 powder, and residual -OH on the surface of the Bi2O2CO3 powder is introduced, then a halogenating agent is added to guide the growth and construction of a composite ternary heterojunction structure. The introduction of Bi can maintain the stable flower-shaped structure of the powder, promote the crystal growth of BiOCl, regulate the proportion of each crystal phase in the heterojunction catalyst to obtain a more effective heterojunction structure, and regulate the morphology to expose the gap of the lamella of the composite powder, effectively improve the active sites and defects, and improve the photocatalytic activity. The method is simple in preparation process, the prepared powder is stable in structure, and the photocatalytic activity of the powder is improved by introducing a heterojunction and a metal element.