CN-116943701-B - Photocatalyst-quantum dot composite material, preparation method and application thereof

CN116943701BCN 116943701 BCN116943701 BCN 116943701BCN-116943701-B

Abstract

The invention belongs to the field of composite materials, and relates to a composite material with formaldehyde-removing antibacterial performance, in particular to a photocatalyst-quantum dot composite material with formaldehyde-removing antibacterial performance and a preparation method thereof, wherein the photocatalyst-quantum dot composite material comprises, by mass, 40% -60% of nano titanium dioxide, 30% -50% of purple carbon quantum dots, 5% -15% of dispersing agents and 1% -5% of silver salts. According to the invention, through the synergistic effect of the carbon quantum dots and the nano titanium dioxide and the assistance of the dispersing agent and silver ions, the transmission of photo-generated electrons can be enhanced, and the recombination of the photo-generated electrons and holes can be inhibited, so that the photocatalysis effect of the nano titanium dioxide is enhanced, and the nano titanium dioxide has the effects of formaldehyde removal, antibiosis and peculiar smell removal.

Inventors

LI JICHAO
YANG FENG
JIANG DAN
XU YUAN

Assignees

浙江世纪豪门家居科技有限公司

Dates

Publication Date: 20260512
Application Date: 20230613

Claims (3)

1. The application of the photocatalyst-quantum dot composite material is characterized in that the photocatalyst-quantum dot composite material accelerates the catalytic decomposition of volatile organic matters and organic dyes under natural light, wherein the volatile organic matters and the organic dyes are formaldehyde and rhodamine B respectively; the photocatalyst-quantum dot composite material comprises the following components in percentage by mass: 40-60% of nano titanium dioxide, 30-50% Of carbon quantum dots, 5-15% Of dispersing agent, 1-5% Of silver salt; the dispersing agent is at least one selected from polycarboxylic acid sodium salt and sulfonic acid sodium salt, and the silver salt is at least one selected from silver nitrate, silver acetate and silver trifluoroacetate; The carbon quantum dot is doped with nitrogen element, the mass percentage of the nitrogen element doping is 1-5%, and the preparation process of the carbon quantum dot doped with nitrogen element comprises the following steps: s1, mixing absolute ethyl alcohol, vanillin and ethylenediamine, carrying out ultrasonic oscillation for 5-20 min, reacting for 6 hours at 200 ℃, and cooling to room temperature to obtain a suspension, wherein the volume-mass ratio of the absolute ethyl alcohol to the vanillin to the ethylenediamine is 10-15ml, and the volume-mass ratio of the absolute ethyl alcohol to the vanillin to the ethylenediamine is 1-2g, and the volume-mass ratio of the absolute ethyl alcohol to the vanillin to the ethylenediamine is 10-15ml; S2, filtering the suspension through a microporous filter membrane with the thickness of 0.1 mu m, diluting filtrate with water to light yellow, centrifuging for 10min at 10000r/min to obtain off-white precipitate, and washing and freeze-drying the precipitate to obtain the nitrogen-doped carbon quantum dots; The carbon quantum dot has a point wavelength of 200-480nm and a particle size of 1-20nm; the preparation method of the photocatalyst-quantum dot composite material comprises the following steps: S1, mixing a formula amount of nano titanium dioxide, carbon quantum dots, a dispersing agent and silver salt with 40-60ml of proper water, and carrying out ultrasonic oscillation to obtain a mixed solution; S2, centrifugally separating the mixed solution to obtain a solid substance, and washing and drying the solid substance to obtain the photocatalyst-quantum dot composite material.
2. The method according to claim 1, wherein the nano-titania has a particle size of 1-30nm.
3. The application of claim 1, wherein the photocatalyst-quantum dot composite material comprises the following components in percentage by mass: 50 percent of nano titanium dioxide, 40 Percent of carbon quantum dots, 7% Of polycarboxylic acid sodium salt, 3% Of silver nitrate.

Description

Photocatalyst-quantum dot composite material, preparation method and application thereof Technical Field The invention belongs to the field of composite materials, relates to a composite material with formaldehyde-removing antibacterial performance, and in particular relates to a photocatalyst-quantum dot composite material with formaldehyde-removing antibacterial performance, a preparation method and application thereof. Background The photocatalyst technology is also called as photocatalysis technology, and the photocatalyst is a general term of semiconductor materials with photocatalysis function represented by nano titanium dioxide. Under the action of ultraviolet light and visible light, the nano titanium dioxide can convert oxygen and water molecules into substances with strong oxidability (such as hydroxyl free radicals, superoxide free radicals and the like), so that volatile organic compounds (such as formaldehyde), bacteria and viruses are decomposed, and the effect of purifying air is achieved. The carbon quantum dots (Carbon Quantum Dots, CQDs) are zero-dimensional carbon nano materials with remarkable fluorescence performance, are composed of ultrafine, dispersed, quasi-spherical carbon nano particles with the size of less than 10nm, and have the advantages of controllable photoluminescence, good stability, low cost and the like. In recent years, quantum dots have been increasingly used in the fields of chemiluminescence, light emitting devices, medical imaging, and the like. At present, the photocatalysis technology mainly uses natural light, but the photocatalysis effect is often greatly reduced due to uncertainty of sunlight irradiation or in places which are difficult to irradiate by sunlight, such as underground parking lots, basements and the like. Disclosure of Invention In order to solve the problem that the photocatalysis effect of the current photocatalysis technology in the background art is often greatly reduced in the uncertainty of sunlight irradiation or in places which are difficult to be irradiated by sunlight, such as underground parking lots, basements and the like, the invention provides a photocatalyst-quantum dot composite material which has the advantage of accelerating catalysis under indoor natural light. The technical scheme adopted for solving the technical problems is as follows: a photocatalyst-quantum dot composite material comprises the following components in percentage by mass: 40-60% of nano titanium dioxide, 30-50% Of carbon quantum dots, 5-15% Of dispersing agent and 1-5% of silver salt. In the prior art, titanium dioxide is used as a photocatalyst to catalyze and convert water molecules and oxygen in the air into strong oxidizing substances so as to achieve the effects of decomposing organic matters, killing bacteria and the like, but the above processes all need to be under the condition of sufficient illumination, especially ultraviolet light. According to the invention, from the angle, nano titanium dioxide is combined with carbon quantum dots to complement the problem of insufficient ultraviolet light, and simultaneously, a dispersing agent and silver salt are added to enhance the transmission of photo-generated electrons, inhibit the recombination of the photo-generated electrons and holes and enhance the photocatalysis effect of the nano titanium dioxide, wherein the carbon quantum dots are selected as carbon quantum dots capable of emitting ultraviolet light. Further, the nano titanium dioxide has a particle size of 1 to 30nm, more preferably 3 to 5nm. Furthermore, the carbon quantum dots are doped with nitrogen element, and the mass percentage of the nitrogen element doping is 1-5%. Further, the carbon quantum dot is emitted to have a wavelength of 200-480nm. The ultraviolet light range is 200-400nm, and the carbon quantum dot is preferably emitted to the wavelength range of 200-480nm in the ultraviolet light range and the blue light range. The quantum dot can adjust the wavelength of the emitted light by changing the particle size of the quantum dot, so that the emitted light with purer chromaticity is obtained. Namely, the ultraviolet light with the emission wavelength of 200-400nm can be obtained by selecting the proper particle size of the carbon quantum dots. Further, the particle diameter of the carbon quantum dots is 1 to 50nm, preferably 2 to 5nm in the present invention. Further, the preparation process of the nitrogen-doped carbon quantum dot comprises the following steps: S1, mixing 10-15mL of absolute ethyl alcohol, 1-2g of vanillin and 10-15mL of ethylenediamine, ultrasonically oscillating for 5-20min, reacting for 6h at 200 ℃, and cooling to room temperature to obtain a suspension; S2, filtering the suspension through a microporous filter membrane with the thickness of 0.1 mu m, diluting the filtrate with water to light yellow, centrifuging for 10min at 10000r/min to obtain an off-white precipitate, and washing and freeze-drying the pre