阅读说明：本技术 一种高产率制备量子点的新方法及改性反渗透膜的应用 (Novel method for preparing quantum dots with high yield and application of modified reverse osmosis membrane ) 是由 董立峰 邵斐斐 于立岩 仪展 于 2020-05-16 设计创作，主要内容包括：本发明涉及一种制备量子点的新方法,以量子点为基体,使用一种表面改性技术,使得量子点表面包覆单宁酸自聚合产物,改性量子点产物结构更加均匀,且大大增大了量子点的产量；并通过掺杂法制备改性聚酰胺反渗透膜,改性膜的通量得到很大程度的提高。通过本专利的方法,可以解决量子点产率低的问题,有效的增大其应用的范围,降低了成本。利用该种新材料制备的聚酰胺改性膜具有增大的通量。新材料的制备将在水处理领域有良好应用前景。(The invention relates to a novel method for preparing quantum dots, which takes the quantum dots as a matrix and uses a surface modification technology to coat the surfaces of the quantum dots with a tannic acid self-polymerization product, so that the modified quantum dot product has a more uniform structure and the yield of the quantum dots is greatly increased; the modified polyamide reverse osmosis membrane is prepared by a doping method, and the flux of the modified membrane is greatly improved. By the method, the problem of low yield of the quantum dots can be solved, the application range of the quantum dots is effectively enlarged, and the cost is reduced. The polyamide modified membrane prepared by the new material has increased flux. The preparation of the new material has good application prospect in the field of water treatment.)

1. The novel method for preparing the quantum dots with high yield is characterized in that the novel quantum dots with high yield are obtained by coating tannin self-polymerization products on the surfaces of the quantum dots serving as carriers.

2. The quantum dot matrix of claim 1, prepared by the following method:

(1) 80ml of citric acid solution (100mg/ml) and 20ml of aqueous ammonia were transferred to a Teflon-lined autoclave and subjected to hydrothermal reaction at 180 ℃ for 12 hours to obtain a pale yellow solution.

(2) The pale yellow solution was dialyzed in deionized water for 4 hours, dialysis bag model (3000Da, Spectrum Lab.Inc.).

(3) Centrifuging the solution in the dialysis bag for three times at 10000rpm, taking supernatant, and drying to obtain powder N-GQOD.

3. The process conditions of the tannin coated quantum dots as claimed in claim 1 are as follows:

(1)100mg of N-GQOD was added to 200ml of Tris-buffer solution (100mM, pH 8.5).

(2) Preparing a Tris-buffer solution: 12.1g of Tris was dissolved in 800ml of purified water, and the pH was adjusted to 8.5 with 4M (1mol/L) HCl to a constant volume of 1L, thereby verifying the pH.

(3)200mg of tannic acid is added into the solution, and the mixture is stirred and reacted for 24 hours at normal temperature.

(4) The resulting solution was subjected to dialysis treatment for 2 d.

(5) Vacuum drying at 35 deg.C for 24 hr to obtain white powder of tannin-modified N-GQOD.

Technical Field

The invention relates to a novel method capable of obviously improving the yield of quantum dots, which is used for preparing a doped modified reverse osmosis membrane and belongs to the field of preparation and application of quantum dots.

Technical Field

The graphene quantum dots are a monodisperse spherical nano carbon material with the size less than 10nm, have the characteristics of good hydrophilicity, mechanical strength, good conductivity and the like, are widely applied to high-precision fields such as new energy batteries and seawater desalination, and the like, but the low yield of the graphene quantum dots is one of bottlenecks restricting the development of the graphene quantum dots. This patent utilizes tannic acid's self polymerization, and at graphite alkene quantum dot cladding polytannic acid, obtain the quantum dot structure of modifying, this quantum dot diameter is comparatively even, and the productivity improves nearly 5 times.

The methods commonly used for preparing graphene quantum dots are divided into top-down methods and bottom-up methods. The number of graphene quantum dots with high quantum yield is still small, and the quantum yield needs to be improved.

Disclosure of Invention

The method adopts the self-polymerization reaction of tannic acid to coat the tannic acid self-polymerization product on an N-GQOD quantum dot matrix, and prepares the novel quantum dot by regulating and controlling the preparation process. TEM shows that the modified material has size of about 5nm and lattice structure and high quantum dot yield.

The invention is realized by the following technical scheme.

The new method for preparing quantum dots with high yield is characterized in that the quantum dots are used as carriers, and tannic acid self-polymerization products are coated on the surfaces of the quantum dots, so that the new quantum dots with the yield doubled are obtained. The self-polymerization reaction of tannic acid on the surface of the quantum dot is as follows:

the quantum dot matrix related to the patent of the invention has the following preparation method:

80ml of citric acid solution (100mg/ml) and 20ml of aqueous ammonia were transferred to a Teflon-lined autoclave and subjected to hydrothermal reaction at 180 ℃ for 12 hours to obtain a pale yellow solution.

The pale yellow solution was dialyzed in deionized water for 4 hours, dialysis bag model (3000Da, Spectrum Lab.Inc.).

Centrifuging the solution in the dialysis bag for three times at 10000rpm, taking supernatant, and drying to obtain powder N-GQOD.

The process conditions for coating the quantum dots with the tannic acid are as follows:

100mg of N-GQOD was added to 200ml of Tris-buffer solution (100mM, pH 8.5).

Preparation of Tris-buffer solution 12.1g of Tris was dissolved in 800ml of purified water, the pH was adjusted to 8.5 with 4M (1mol/L) HCl, and the volume was 1L to verify the pH.

200mg of tannic acid is added into the solution, and the mixture is stirred and reacted for 24 hours at normal temperature.

The resulting solution was subjected to dialysis treatment for 2 d.

Vacuum drying at 35 deg.C for 24 hr to obtain white powder of tannin-modified N-GQOD.

And (3) using a doping method to modify the reverse osmosis membrane by using the prepared quantum dots and the modified quantum dots to obtain the modified polyamide reverse osmosis membrane.

Drawings

FIG. 1 is a TEM image of matrix quantum dots

FIG. 2 is TEM image of quantum dots after tannic acid modification

Detailed Description