A composite titanium dioxide interface bonding sterilizing agent and a preparation method thereof

Abstract

The application discloses a composite titanium dioxide interface bonding sterilizing agent and a preparation method thereof, and belongs to the technical field of inorganic antibacterial materials. The sterilizing agent is in-situ compounded by anatase titanium dioxide, cerium bromide and silver iodide, and the molar amount of the cerium bromide is 0.02-0.08 and the molar amount of the silver iodide is 0.04-0.20, with the molar number of the titanium dioxide being 1. The components are compounded through crystal face matching, chemical bond matching and energy band gradient matching to form a continuous interface bonding structure of Ti-O-Ce-Br-Ag-I and constitute a ternary coherent heterojunction. The application realizes efficient cooperation through crystal face matching, chemical bond matching and energy band gradient matching, generates high-activity oxygen species under visible light to realize rapid sterilization, realizes long-acting bacteriostasis through controllable release of Ag+ and I-, and improves the stability of the system by means of Ce3+ / Ce4+ circulation. The preparation adopts a low-temperature alcohol heating process, is suitable for industrial production, and has the advantages of mild conditions, no calcination and the like. The obtained sterilizing agent has the advantages of fast sterilization, long bacteriostasis period, high stability, non-toxicity, environmental protection and the like, and can be applied to the fields of medical disinfection, water treatment, air purification and antibacterial coating and the like.

Description

Technical Field

[0001] This invention belongs to the technical field of inorganic antibacterial materials and photocatalytic sterilization materials. Specifically, it relates to an interfacial bonding sterilizing agent that is precisely composited based on the crystal structure, chemical bond characteristics and band structure of silver iodide, cerium bromide and titanium dioxide, and its low-temperature in-situ preparation method. Background Technology

[0002] Titanium dioxide (TiO2) has advantages such as high chemical stability, non-toxicity, and low cost. However, it has a wide band gap, only responds to ultraviolet light, has a high recombination rate of photogenerated electron-hole pairs, has limited sterilization efficiency, and does not have long-lasting antibacterial ability.

[0003] Silver iodide (AgI) has good visible light response and broad-spectrum antibacterial properties, but it has defects such as easy aggregation, silver ion burst release, easy photocorrosion, and poor structural stability.

[0004] Cerium bromide (CeBr3) has unique Ce3+ / Ce4+ redox cycle characteristics and can be used as a highly efficient electron trap, but it has poor dispersibility when used alone and is difficult to form a stable interface with TiO2.

[0005] Currently, most of the publicly available technologies involve physical mixing, simple impregnation, or ordinary deposition of composite materials. They are not rationally designed based on crystal structure matching, chemical bond matching, and band structure matching. As a result, they generally suffer from problems such as weak interfacial bonding, low electron transport efficiency, insufficient synergistic effect, and poor antibacterial durability.

[0006] To date, no patents or literature disclose the construction of a ternary heterojunction sterilizing agent with continuous interfacial bonding of Ti–O–Ce–Br–Ag–I based on molecular structure matching. This invention is completely novel in terms of structural design, bonding mode, band structure regulation, and preparation route. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a ternary composite sterilizing agent based on molecular structure matching, strong interfacial bonding, strong visible light response, rapid sterilization and long-lasting antibacterial effect, and high stability, and provides an industrially feasible preparation method for it.

[0008] A composite titanium dioxide interfacial bonding sterilizing agent, characterized in that: It is composed of three components—anatase phase titanium dioxide, cerium bromide, and silver iodide—in situ composite based on crystal structure matching, chemical bond matching, and band gradient matching. The molar ratio is: With one mole of titanium dioxide, the molar amount of cerium bromide is 0.02~0.08, and the molar amount of silver iodide is 0.04~0.20. The components form a continuous interfacial chemical bond structure of Ti–O–Ce–Br–Ag–I, constituting a coherent ternary heterojunction.

[0009] Molecular structure matching mechanism 1. Crystal plane matching The lattice parameters of the anatase TiO2 (101) crystal plane are highly compatible with those of the AgI (002) and CeBr3 (110) crystal planes, enabling coherent epitaxial growth and reducing interface defects.

[0010] 2. Chemical bond matching The hydroxyl groups on the surface of TiO2 form Ti–O–Ce chemical bonds with Ce; Ce–Br forms a coordination relationship with Ag+; Ag+ reacts with I- to form AgI crystals; Ultimately, a continuous, stable, and dense interface bonding network is formed.

[0011] 3. Band gradient matching The CeBr3 energy level is located between TiO2 and AgI, forming a stepped band structure that enables directional electron migration and efficient separation, significantly suppressing carrier recombination.

[0012] Triple synergistic sterilization mechanism 1. Photocatalytic rapid sterilization Ternary heterojunctions generate a large number of reactive oxygen species such as •OH and •O2- under visible light, which rapidly destroy bacterial cell walls, cell membranes and nucleic acids.

[0013] 2. Ion-release sustained-release antibacterial effect Ag+ and I- can be released slowly and controllably through interfacial coordination bonds, achieving rapid sterilization in 1 minute and continuous antibacterial activity for more than 7 days.

[0014] 3. Enhanced Ce3+ / Ce4+ redox cycle Cerium ions cyclically capture electrons, inhibiting AgI photocorrosion and improving system stability and antibacterial durability.

[0015] The beneficial effects of this invention are: 1. High novelty: Based on molecular structure matching design, a ternary heterojunction structure with continuous interface bonding is constructed, with no overlap with existing patents and literature.

[0016] 2. Outstanding creativity: It is not a simple combination of three substances, but achieves strong interactions through atomic-level interfacial bonding, resulting in unexpected synergistic effects.

[0017] 3. Strong interfacial bonding: Ti–O–Ce–Br–Ag–I continuous bonding, no detachment, no aggregation, and slow and controllable release of silver ions.

[0018] 4. Excellent sterilization performance: sterilization rate greater than 99.99% in 1 minute, and antibacterial time of no less than 7 days under dark conditions.

[0019] 5. It has high visible light response efficiency and significantly improved photogenerated carrier separation efficiency.

[0020] 6. High stability: Resistant to light exposure and erosion, does not easily discolor, and has stable performance in repeated use.

[0021] 7. Mild preparation process: It adopts low-temperature alcohol heating, without the need for high-temperature calcination, the process is controllable and suitable for industrial production. Detailed Implementation

[0022] Step 1: Activation of hydroxyl groups on TiO2 surface Nano-anatase TiO2 was dispersed in a water-ethylene glycol mixed solvent, sonicated for 30 minutes, and heated to 50-65℃ to allow Ti–OH active sites to be fully formed on the surface.

[0023] Step 2: In-situ anchoring of CeBr3 Add CeBr3 solution and stir for 40 minutes. Ce3+ forms Ti–O–Ce chemical bonds with Ti–OH, achieving monodisperse layer loading.

[0024] Step 3: Ag+ coordination adsorption Add silver nitrate solution, stir at low temperature and in the dark for 30 minutes, and Ag+ and Ce–Br form Ce–Br→Ag+ coordination structure, which is uniformly dispersed and does not agglomerate.

[0025] Step 4: I-in-situ structural bonding Potassium iodide solution was slowly added dropwise, and AgI was generated in situ, forming a continuous interface structure with CeBr3–TiO2.

[0026] Step 5: Low-temperature alcohol thermal crystallization Holding at 85~110℃ for 2~4 hours promotes crystal plane matching and interface bonding, and prevents the formation of impurity phases.

[0027] Step 6: Post-processing Centrifugation, washing with deionized water and ethanol, and vacuum drying yield the final composite titanium dioxide interfacial bonded sterilizing agent.

[0028] The sterilizing agent prepared by this invention has a fast sterilization speed, long antibacterial period, strong visible light response, high stability, and low toxicity. The preparation process is mild and controllable, suitable for industrial production, and can be widely used in medical disinfection, water treatment, air purification, antibacterial coatings and other fields.

Claims

1. A composite titanium dioxide interfacial bonding sterilizing agent, characterized in that, It is composed of anatase phase titanium dioxide, cerium bromide and silver iodide in situ. Taking the molar amount of titanium dioxide as 1, the molar amount of cerium bromide is 0.02~0.08 and the molar amount of silver iodide is 0.04~0.

20. The components are combined through crystal plane matching, chemical bond matching and band gradient matching to form a Ti-O-Ce-Br-Ag-I continuous interfacial bonding structure, which constitutes a ternary coherent heterojunction.

2. The composite titanium dioxide interfacial bonding sterilizing agent according to claim 1, characterized in that, Cerium bromide has energy levels between those of titanium dioxide and silver iodide, forming a stepped band structure.

3. A composite titanium dioxide interfacial bonding sterilizing agent according to claim 1 or 2, characterized in that, The sterilizing agent generates reactive oxygen species under visible light and can release silver ions and iodine ions, while also having cerium ion redox cycle sites.

4. A method for preparing a composite titanium dioxide interfacial bonded sterilizing agent according to any one of claims 1 to 3, characterized in that, The process includes the following steps: Step 1: Disperse anatase phase titanium dioxide in a water-ethylene glycol mixed solvent, ultrasonically disperse and heat-activated to form Ti-OH active sites on the titanium dioxide surface; Step 2: Add cerium bromide solution and stir to allow cerium ions to bond with Ti-OH to form a Ti-O-Ce structure; Step 3: Add silver nitrate solution and stir in the dark to allow silver ions to form a coordination structure with cerium-bromine; Step 4: Add potassium iodide solution dropwise to generate silver iodide in situ and form a continuous interfacial bonded structure; Step 5: Perform low-temperature alcoholic thermal crystallization at 85℃~110℃; Step 6: After centrifugation, washing and vacuum drying, obtain the composite titanium dioxide interfacial bonded sterilizing agent.

5. A composite titanium dioxide interfacial bonding sterilizing agent according to any one of claims 1 to 3, characterized in that, Used for medical and health applications, drinking water treatment, air purification, antibacterial coatings, food contact materials, or disinfection of public environments.