9 results about "Bismuth titanate" patented technology

The invention discloses a texture preparation method for high-performance lead-free piezoelectric ceramics of bismuth ferrite-barium titanate. The general formula of the ceramic composition is as follows, where the molar fraction ratio of BiFeO3 and BaTiO3 is 2:1, x, y, t, and m all represent molar fractions, and 0 < x ≤ 0.05, 0 < y ≤ 0.05, 0 < t ≤ 0.05, 0 < m ≤ 0.05. In the sintering stage of the invention, a temperature gradient field is constructed to make the ceramic grains grow texture-directionally, and a textured piezoelectric ceramic with a piezoelectric constant d 33 reaching above 1000 pC / N at 350 °C and a T dr reaching above 350 °C is obtained. The preparation process of the invention is simple, and the prepared ceramic has excellent high-temperature performance and can be applied to the field of high-temperature piezoelectricity.

The application discloses a preparation method of a sheet-shaped Nb element doped modified bismuth titanate catalyst material. 3‑x Nb x O 12 , wherein 0.15<=x<=0.40, the molar ratio of Bi, Ti and Nb is taken as bismuth oxide, titanium dioxide and niobium pentoxide; step two: the raw materials in step one and the mass ratio of the molten salt are mixed, then the mixture is put into a crucible and fully grinded to obtain a mixture; step three: the mixture prepared in step two is fired in a muffle furnace, and a light yellow product is obtained after cooling; step four: the light yellow product prepared in step three is washed with deionized water, filtered and dried to obtain a sheet-shaped Nb element doped bismuth titanate catalyst powder. The technology can significantly improve the structural uniformity, defect concentration and piezoelectric response activity of the material, greatly reduce the energy consumption and time cost, provides an efficient path for large-scale production of high-performance catalysts, and has a wide market prospect.

This invention belongs to the field of biomedical materials technology, and relates to a piezoelectrically enhanced nanoenzyme composite material, its preparation method, and its antibacterial application. Cobalt-doped molybdenum disulfide is grown in situ on the surface of bismuth titanate nanosheets to obtain a BTO@Co-MoS2 composite material. This composite material exhibits a piezoelectric effect under pressure stimulation. Electrons, under the influence of the built-in electric field at the BTO@Co-MoS2 interface, promote the self-cycling of the molybdenum disulfide redox pair, thereby improving the catalytic activity of halogen-like peroxidases. Simultaneously, the piezoelectric catalysis of hydrogen peroxide generation alleviates the problem of insufficient endogenous hydrogen peroxide. In antibacterial applications, the piezoelectrically enhanced nanoenzyme composite material prepared by this invention achieves bactericidal rates of 98.39% and 99.95% against Staphylococcus aureus and Escherichia coli, respectively.

This invention relates to the field of piezoelectric ceramics technology, and in particular to a composite ion-modified bismuth layered bismuth titanate calcium-based high-temperature piezoelectric ceramic and its preparation method. The general formula for high-temperature piezoelectric ceramics is: Ca 1‑x (LiCe) x / 2 Bi 3.75 Nd 0.25 Ti 3.935 Sc 0.065 O 15 , where x is a complex high-valence ion (LiCe). 4+ Twice the molar amount, x = 0.02, 0.05, 0.08, 0.10. This invention employs the above-mentioned composite ion-modified bismuth layered bismuth titanate calcium-based high-temperature piezoelectric ceramic and its preparation method to meet the application requirements in high-temperature environments while ensuring the material's environmental friendliness.

The application relates to the technical field of catalysts, and particularly discloses a sulfur-tolerant shift catalyst as well as a preparation method and application thereof. The sulfur-tolerant shift catalyst provided by the application comprises the following components in parts by weight: a carrier, an active component and an additive; the carrier is an acid-modified attapulgite-bismuth titanate composite carrier; the active component is CoO and MoO3, and the loadings of the active component in the catalyst are 2-5 wt% and 8-12 wt% respectively; wherein, the preparation method of the acid-modified attapulgite-bismuth titanate composite carrier comprises the following steps: preparing an acid-modified attapulgite, preparing a bismuth titanate precursor solution, compounding and calcining and activating. The sulfur-tolerant shift catalyst provided by the application has the advantages of low preparation cost, high catalytic activity, good stability and the like, and has a good application prospect.

This invention provides a method for preparing bismuth titanate nanoparticles using molten salt assistance. Sodium bismuthate dihydrate, sodium sulfite, titanium sulfate, and sodium nitrate are mixed and ground uniformly to obtain a solid mixture. The solid mixture is then heated at 350°C to melt the sodium nitrate, creating an ion-molten liquid environment. Under this environment, a redox reaction between sodium bismuthate dihydrate and sodium sulfite generates the transition product bismuth oxysulfate, producing sodium hydroxide and creating a self-generated alkaline condition. Simultaneously, under this self-generated alkaline condition, bismuth oxysulfate reacts with titanium sulfate to form bismuth titanate. The reaction product is then post-processed to obtain Bi... 24 Ti2O 40 Nanoparticles. The advantages of this invention are: a synthesis strategy based on an ion-molten liquid environment, accelerated reactant diffusion, and improved chemical reaction efficiency to prepare Bi. 24 Ti2O 40 Nanopowders are easy to prepare, convenient to operate, have a mild reaction, and are low in cost, making them suitable for industrial production.

The application belongs to the technical field of functional composite materials and piezoelectric materials, and specifically discloses a bismuth titanate powder filled polyvinyl fluoride composite piezoelectric film and a preparation method thereof. The preparation method comprises the steps of raw material preparation, preparation of a PVDF composite solvent system, addition and uniform dispersion of fillers, blade coating, low-temperature vacuum drying and stripping. The application realizes the uniform dispersion of bismuth titanate powder or manganese and niobium co-doped bismuth titanate powder in a PVDF matrix by optimizing the ratio of a DMF and acetone composite solvent system, adopting a combined ultrasonic dispersion mode, and introducing a blade coating film forming process and a low-temperature rapid vacuum drying process. Meanwhile, the mass ratio of raw materials is precisely controlled. On the basis of simplifying the preparation process and shortening the film forming period, the piezoelectric performance and structural compactness of the composite film are improved, and the defects of the existing preparation method, such as uneven filler dispersion, insufficient flexibility, low film forming efficiency, and limited improvement of the piezoelectric performance of the film, are solved.

This invention belongs to the field of nanocomposite materials and spectroscopic detection technology. This invention discloses an Ag / Co-Bi4Ti3O... 12 Composite SERS substrate, its preparation method, and its application in the detection of crystal violet molecules in water: First, cobalt-doped bismuth titanate (Co-Bi4Ti3O) was prepared using a hydrothermal-calcination method. 12 Ag / Co-Bi4Ti3O was prepared by loading silver nanoparticles onto the surface of a carrier using sodium citrate as a reducing agent. 12 Composite SERS substrate. This invention utilizes cobalt doping to modify and optimize Bi4Ti3O. 12 By combining the electromagnetic enhancement effect of localized surface plasmon resonance of silver nanoparticles with the chemical enhancement effect of semiconductor charge transfer, a dual synergistic SERS enhancement system is constructed, solving the problems of weak enhancement effect of traditional SERS substrates, easy aggregation of silver particles, and poor detection uniformity and cycling stability. This enables ultra-trace, rapid, and highly sensitive Raman detection of crystal violet in water.

The application provides a zirconium titanate strontium bismuth-based ceramic material with high energy storage density and a preparation method thereof, and relates to the technical field of ceramic capacitor material processing. 0.88 Bi 0.08 Ti 1‑x Zr x O3, and 0<=x<=1, and the preparation process of the ceramic material mainly comprises the steps of raw material preparation, ball milling, pre-sintering ball milling, forming treatment and the like. The application introduces a wide-band-gap oxide on the basis of adding Bi elements, overcomes the defects of the prior art, and the prepared ceramic material has full grains and is densely stacked. The energy storage performance of the ceramic prepared under the prior art is improved to 5.97 J / cm 3 , and in addition, the energy storage density is stable within the temperature range of 30-180 DEG C at ±5%, and can be applied to high-temperature environment energy storage devices.