6results about How to "Uniform shape and size" patented technology

The invention relates to the technical field of high-performance composite materials, and provides a frequency band magnetic control adjustable one-dimensional nanotube composite wave-absorbing material and a preparation method thereof.The material is composed of a one-dimensional tubular ferroferric oxide matrix and manganous-manganic oxide wrapping the outer side of the matrix, and directional arrangement is conducted through magnetic control rotation. The preparation method comprises the following steps: preparing an iron oxyhydroxide precursor through a hydrothermal synthesis method; the preparation method comprises the following steps: reducing an iron oxyhydroxide precursor by a liquid-phase pyrolysis method, and coating a manganous-manganic oxide shell layer in situ at the same time, so as to obtain a nanotube ferroferric oxide / manganous-manganic oxide composite material; and carrying out orientation arrangement on the nanotube-shaped ferroferric oxide / manganous-manganic oxide composite material through magnetic field control. According to the preparation method and the structural design, the yield, the uniformity, the magnetic performance, the electromagnetic wave absorption efficiency, the multi-band electromagnetic loss enhancement and the like of the material are remarkably improved.

The invention relates to a magnetic nanorod, in particular to a preparation method and application of the magnetic nanorod. The invention develops a simple strategy to synthesize the magnetic nanorod with peroxidase (POD) activity, the magnetic nanorod can be used as a nanoenzyme and can also be used as a magnetic stirring nanorod for a micro-catalytic reaction, and the magnetic nanorod is used in a microfluidic system to realize quantitative detection of an object to be analyzed. The method has the advantages of mild conditions, greenness and higher controllability on the particle size. A dynamic nano-enzyme system is constructed on the basis of the magnetic nanorod to quantitatively detect cysteine. Compared with the static nano-enzyme, the dynamic nano-enzyme has the advantages that the enzyme activity can be maximally three times of the original enzyme activity, and the reaction kinetics is obviously enhanced.

The invention discloses a composite heterojunction photocatalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out pre-reaction on a first mixed system at least containing an aldehyde substance, an amine substance, a two-dimensional nanosheet and a catalyst, and then heating in a vacuum or inert atmosphere for continuous reaction to prepare the covalent organic framework nanotube / two-dimensional nanosheet composite heterojunction photocatalyst. According to the method, no soft / hard template is used, reversible Schiff base chemical bonds and proton tautomerization are utilized, hollow nanotubes are constructed on the surface of a two-dimensional nanosheet layer material in situ through a one-pot method which is easy to operate from bottom to top, the composite heterojunction photocatalyst is obtained, and meanwhile the composite heterojunction photocatalyst is high in crystallinity and good in photocatalytic performance. And the material has a large specific surface area, and has potential application value in the fields of adsorption, separation and photocatalytic antibiosis and antifouling.

This invention belongs to the field of hollow multi-component nanomaterial preparation technology, specifically disclosing a hollow Cu3NbSe4 nanomaterial, its preparation method, and its application. The microstructure of the nanomaterial is a nanoscale hollow cubic structure. The preparation method includes: (1) dissolving niobium source and selenium source separately in oleylamine solvent by heating for later use; (2) treating the soluble copper source and the niobium source dissolved in (1) in a high-boiling-point organic solvent for deoxygenation and dehydration, and then carrying out a solvothermal reaction; (3) when (2) is heated to a certain temperature, injecting the selenium source dissolved in (1) to carry out a solvothermal reaction, and separating the obtained solid product after the reaction is completed. The synthesis process of this invention is simple, the reaction conditions are mild, and the energy consumption and cost are low; more importantly, it realizes the preparation of hollow Cu3NbSe4 nanomaterial with uniform morphology and size, high crystallinity, and stronger light absorption capacity, and the prepared hollow Cu3NbSe4 shows excellent performance in photocatalytic hydrogen production.

The invention discloses an inorganic halide perovskite material with low thermal conductivity and a preparation method and application thereof. The molecular formula of the inorganic halide perovskite material with low thermal conductivity is Rb4Sb2Br12; the inorganic halide perovskite material with low thermal conductivity is a quadruple perovskite material and belongs to an I41 / a space group of a tetragonal system; the inorganic halide perovskite material with low thermal conductivity is composed of a SbBr6 < 3-> octahedral framework, Rb atoms occupy cavities among octahedrons, and Sb is in a mixed valence state of + 3 and + 5; the Rb4Sb2Br12 perovskite single crystal prepared by the method is complex in structure, pollution-free, low in price and simple to prepare, has intrinsic low thermal conductivity, and can grow into large blocks; the intrinsic thermal conductivity of the Rb4Sb2Br12 single crystal at normal temperature can reach 0.24 Wm <-1 > K <-1 >, and the intrinsic thermal conductivity of the Rb4Sb2Br12 single crystal at 150 DEG C can reach 0.21 Wm <-1 > K <-1 >, so that the Rb4Sb2Br12 single crystal is a very promising low-thermal-conductivity material.

The invention provides an etching solution for stably etching a molybdenum-containing metal lamination. The etching solution comprises 60-70% of phosphoric acid, 1-5% of nitric acid, 10-20% of acetic acid, 1.5-8% of an additive and the balance of ultrapure water. The MoOx / Mo / Al / Mo laminated layer is etched by the etching solution, the top molybdenum and the bottom molybdenum are both reduced slightly relative to the aluminum layer, and the variances of the critical dimensional deviation (CD Bias), the inclination angle (Taper), the dimensional deviation (Mo Tip) of the top molybdenum relative to the aluminum and the dimensional deviation (Mo Tail) of the bottom molybdenum relative to the aluminum are remarkably reduced, so that the morphology and the size of the etched MoOx / Mo / Al / Mo laminated layer are more uniform, and the improvement of the product etching yield is facilitated.