Rare earth composite antibacterial material and preparation process thereof

Abstract

This invention belongs to the technical field of inorganic functional antibacterial materials, and provides a rare earth composite antibacterial material and its preparation process. The material comprises spherical nano-zinc oxide substrate particles, rare earth oxide nanodomains distributed on and / or near the surface of these particles, an interface anchoring layer between them, and a surface compatibility layer coating the outer surface of the composite particles. The rare earth oxides are selected from one or more of CeO2, La2O3, Nd2O3, Sm2O3, and Y2O3. The process includes preparing spherical nano-zinc oxide through zinc salt atomization pyrolysis or aerosol reaction, followed by pre-anchoring treatment, introduction of rare earth salt adsorption and alkalization deposition, heat treatment to form nanodomains, and then surface compatibility treatment to obtain the product. This material exhibits high dispersion stability, the active components are not easily migrated or detached, and the antibacterial effect is long-lasting, making it suitable for coatings, plastics, fibers, and building material systems.

Description

Technical Field

[0001] This invention belongs to the field of inorganic antibacterial materials and nanomaterials technology, specifically relating to a rare earth composite antibacterial material and its preparation process. Background Technology

[0002] Inorganic antibacterial materials are widely used in textiles, plastics, coatings, and ceramics due to their good heat resistance and wide applicability. In existing technologies, nano-zinc oxide is used as an antibacterial component due to its certain antibacterial ability. However, in practical applications, it often faces problems such as easy particle aggregation, insufficient dispersion stability in complex matrices, low utilization rate of effective antibacterial sites, and the need for high addition amounts, making it difficult to simultaneously achieve antibacterial effect and processing compatibility. Introducing rare earth elements into the zinc oxide system is one of the common enhancement pathways, but different schemes may still have shortcomings in terms of the distribution morphology of rare earth components, interfacial bonding stability, and compatibility with downstream systems, thus affecting antibacterial durability and application compatibility.

[0003] Patent application CN118303425A discloses a method for preparing a rare-earth-doped nano-zinc oxide antibacterial agent and antibacterial masterbatch. This method involves introducing zinc and rare-earth element precursors and then drying and calcining them to obtain the rare-earth-doped nano-zinc oxide antibacterial agent, aiming to improve the problems of agglomeration and insufficient antibacterial effect of pure nano-zinc oxide during use. However, this method mainly relies on doping modification and may still have limitations such as difficulty in finely controlling the doping distribution and interface stability, insufficient long-term dispersion and compatibility in various application media, thus leaving room for improvement in achieving stable and long-lasting antibacterial effects in complex systems.

[0004] Chinese patent application CN114557365A discloses a composite nano-zinc oxide, nano-slurry, its preparation method, and applications. This method involves introducing dispersants, catalysts, and stabilizers into a zinc oxide system, followed by grinding steps to obtain the nano-slurry for use in coatings, textiles, plastics, and ceramics. However, this approach focuses on formulation-based compounding to improve dispersion and ease of use. It may not provide targeted structural support for addressing issues such as achieving stable loading and spatial distribution control of rare earth active components at the particle level, and suppressing the migration and performance degradation of active components during use.

[0005] Chinese patent application CN110170318A discloses a rare earth element-doped nano-zinc oxide and its application, which improves related properties by introducing rare earth components to obtain rare earth-doped nano-zinc oxide materials. However, this doping approach may still face problems such as difficulty in maintaining stable doping morphology and surface interface state in different application scenarios, as well as insufficient compatibility with different matrix systems, thus affecting the durability and repeatability of antibacterial properties.

[0006] Therefore, how to provide a rare earth composite antibacterial material and its preparation process to solve or overcome the technical problems of existing nano zinc oxide antibacterial materials such as easy agglomeration, insufficient antibacterial durability, and poor compatibility with application systems, and to achieve stable and long-lasting broad-spectrum antibacterial effects with low addition amounts, is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0007] To address the deficiencies in the existing technology, this invention provides a rare earth composite antibacterial material and its preparation process. This material is prepared by constructing rare earth oxide nanodomains on the surface and / or near the surface of spherical zinc oxide nanoparticles, setting an interface anchoring layer between the rare earth oxide nanodomains and the spherical zinc oxide nanoparticles, and coating the composite particles with a surface compatibility layer. This improves the binding stability of rare earth active sites and the dispersion stability of the material, reduces agglomeration, and enhances the antibacterial durability.

[0008] In a first aspect, the present invention provides a rare earth composite antibacterial material, comprising: spherical nano zinc oxide substrate particles, rare earth oxide nano domains, an interface anchoring layer, and a surface compatibility layer; The rare earth oxide nanodomains are rare earth oxide particles distributed on the surface and / or near the surface of the spherical nano zinc oxide substrate particles, and the rare earth oxides are selected from one or more of CeO2, La2O3, Nd2O3, Sm2O3, and Y2O3. The interface anchoring layer is located between the rare earth oxide nanodomain and the spherical nano zinc oxide substrate particles, and the interface anchoring layer includes one or more of the following: condensed phosphate and its salt, phytate, phosphonate, and coordination molecules containing catechol groups. The spherical zinc oxide nanoparticles, the rare earth oxide nanodomains, and the interface anchoring layer together constitute the composite particles. The surface compatibility layer is coated on the outer surface of the composite particles, and the surface compatibility layer includes one or more of the following: silane coupling layer, polysiloxane layer, and polyacrylate polymer brush layer.

[0009] This invention employs spherical nano-zinc oxide as the substrate particle, providing a relatively uniform carrier and processable morphology. This allows rare earth oxides to form discretely distributed active sites and interface regions on the surface and / or near-surface layer at the nanoscale. On one hand, this enhances charge separation and surface redox reaction processes through the regulation of interface electronic and defect states, increasing the continuous generation capacity of reactive oxygen species. This results in stronger oxidative damage to bacterial cell membranes and intracellular components, improving antibacterial efficiency and stability. On the other hand, the interface anchoring layer utilizes the coordination adsorption of condensed phosphates and their salts, phytates, phosphonates, or catechol-containing coordinating molecules with the metal oxide surface to stably fix the rare earth oxide nanodomains to the zinc oxide substrate surface, reducing performance degradation caused by the migration, shedding, and aggregation of active components. Simultaneously, the surface compatibility layer uses silane coupling, polysiloxane, or polyacrylate structures to compatibility treat the outer surface of the particles, improving the wetting and dispersion stability of the composite particles in different organic or aqueous systems, inhibiting secondary aggregation, and improving processing adaptability. This allows for a more durable and stable antibacterial effect even at lower addition levels.

[0010] Preferably, the median particle size D50 of the spherical nano zinc oxide substrate particles is 20-300 nm, and the sphericity is not less than 0.85.

[0011] The aforementioned particle size range allows the substrate particles to maintain the advantages of high specific surface area and surface reactivity at the nanoscale while avoiding strong agglomeration and dispersion instability caused by excessively high surface energy due to excessively small particle size. This provides a more controllable bearing interface for rare earth oxides to form a stable and uniform distribution of active sites on their surface and / or near-surface. On the other hand, higher sphericity helps reduce mechanical interlocking and frictional resistance between particles, improves powder flowability and system wetting and dispersion efficiency, reduces secondary agglomeration during shear mixing or ultrasonic dispersion, and makes it easier for composite particles to achieve stable dispersion in aqueous or organic media. This helps maintain the effective exposure and long-term availability of antibacterial active centers under different processing and usage conditions, and improves the stability and durability of antibacterial effects.

[0012] Preferably, the rare earth oxide nanodomains have an average particle size of 1-20 nm and are distributed in a discrete island or lattice pattern on the surface of the spherical nano zinc oxide substrate particles.

[0013] Rare earth oxides, distributed on the ZnO surface at a microscale of 1-20 nm in a discrete island or lattice pattern, can form a higher density of rare earth oxide / ZnO interface regions and effectively exposed active sites per unit mass of material. This is more conducive to charge separation and transfer at the interface, reduces carrier recombination, and increases the probability of surface redox reactions. It promotes the continuous generation of reactive oxygen species such as superoxide radicals and hydroxyl radicals, thereby enhancing the oxidative damage to bacterial cell membranes and intracellular components and improving antibacterial efficiency and stability. At the same time, the discrete distribution avoids the formation of a continuous coating layer of rare earth phase that would obscure the effective surface of ZnO, taking into account both interfacial synergy and the intrinsic surface effects of ZnO, so that the material can maintain a more durable antibacterial performance even at a lower addition amount.

[0014] Preferably, the interface anchoring layer comprises condensed phosphates and their salts and / or phytates and / or phosphonates and / or coordination molecules containing catechol groups.

[0015] Under the aforementioned constraints, phosphate or phosphonic acid groups in the interfacial anchoring layer can undergo strong adsorption or chemisorption with metal sites on the metal oxide surface, forming a relatively stable metal-oxygen bond structure. This more firmly fixes the rare earth oxide nanodomains onto the surface of the spherical zinc oxide nanoparticles and inhibits their migration and detachment in mixed shearing, washing, or salt ion environments. Phytate, with its multidentate phosphate groups, readily forms multi-site chelate complexes with metal ions, constructing a dense and stable interfacial complex layer, which further enhances the interfacial bonding strength and durability. Coordinating molecules containing catechol groups can enhance the adhesion and fixation effect on the oxide surface through coordination bonding and hydrogen bonding. Therefore, the spatial distribution of the rare earth oxide nanodomains is more easily maintained, and the active interface of the composite particles is more stably exposed, thus contributing to a more durable antibacterial performance and reducing the risk of performance degradation during use.

[0016] Preferably, the interface anchoring layer is a dual anchoring layer structure, comprising an inorganic anchoring inner layer and an organic coordination outer layer located outside the inorganic anchoring inner layer; the inorganic anchoring inner layer comprises one or more of condensed phosphates and their salts, and the organic coordination outer layer comprises one or more of coordination molecules containing catechol groups and / or phosphonates.

[0017] The condensed phosphates and their salts in the inorganic anchoring inner layer can form strong adsorption bonds on the zinc oxide surface (e.g., through polydentate or bidentate coordination with surface metal sites), thereby constructing a stable "bottom anchoring interface" between the substrate particles and the rare earth oxide nanodomains, reducing the risk of migration and desorption of the rare earth oxide nanodomains under shear mixing, washing, or electrolyte environments. Furthermore, the catechol-containing coordination molecules and / or phosphonates in the organic coordination outer layer can undergo coordination adsorption with the metal oxide surface and form a more flexible outer layer binding network. While enhancing the interfacial binding strength, this provides a certain steric hindrance and compatibility transition for the particle surface, making the composite particles less prone to secondary aggregation during dispersion and helping to maintain the effective exposure of active sites for a long time, thereby improving the stability and durability of antibacterial performance.

[0018] Preferably, the composite particles further include a confined coating layer, which is disposed outside the surface compatibility layer. The confined coating layer is a porous silica layer and / or an organosilicon network layer, and the thickness of the confined coating layer is 10-50 nm.

[0019] As a "porous barrier and structural framework" located on the outermost side of the particles, the confined coating layer can, on the one hand, gently regulate the contact process between the external medium and the particle surface through a continuous or semi-continuous silica network without significantly obscuring the effective sites on the surface of the composite particles. This reduces secondary agglomeration and interfacial instability of the composite particles during dispersion, shear mixing, and service, thereby improving the colloidal stability and end-use dispersion stability of the system. On the other hand, the shell thickness and pore structure of the porous silica layer or organosilicon network layer can be adjusted at the nanoscale, allowing small molecules such as external moisture and ions to maintain diffuseable channels while inhibiting the dissolution or structural degradation of the core zinc oxide component, and helping to maintain the long-term stability of antibacterial activity. Among these, silica coating is often used in nanomaterials to improve particle stability and provide additional surface controllability without weakening the target function, while the surface modification of zinc oxide particles by the organosilicon network also helps to improve its dispersibility and matrix compatibility, thereby comprehensively improving the material's processing adaptability and antibacterial durability.

[0020] Preferably, the rare earth oxide nanodomains include CeO. 2-x , where x is 0.01-0.20.

[0021] CeO 2-x This indicates the presence of a certain proportion of oxygen-deficient sites in the cerium oxide lattice, accompanied by Ce. 3+ With Ce 4+ The reversible transformation, the hypoxia site can serve as an interface site for oxygen molecule adsorption and reaction activation, and through Ce 3+ / Ce 4+Redox cycles promote surface electron transfer and oxygen storage and release processes, thereby increasing the probability of surface redox reactions and promoting the continuous generation of reactive oxygen species. This can enhance the oxidative damage to bacterial cell membranes and intracellular components, making the antibacterial effect more stable and longer-lasting. At the same time, with the scale and distribution of rare earth oxide nanodomains under control, it is beneficial to maintain high effective antibacterial activity under low addition conditions.

[0022] Preferably, the surface compatibility layer comprises a coupling layer formed by an organosilane coupling agent, wherein the functional group of the organosilane coupling agent is selected from one or more of amino, epoxy, and methacryloxy groups, and / or the surface compatibility layer comprises a polyacrylate polymer brush layer containing carboxyl groups.

[0023] Organosilane coupling agents typically possess a bifunctional structure with both a hydrolyzable silane end and an organic functional group end. After hydrolysis, the hydrolyzable group undergoes a condensation reaction with the hydroxyl groups on the surface of inorganic oxides such as zinc oxide, forming stable silicon-oxygen bonds that firmly anchor the coupling layer to the surface of the composite particles. Simultaneously, organic functional groups such as amino, epoxy, or methacryloxy groups can interact with the downstream matrix or modified components through polar interactions, ring-opening reactions, or free radical copolymerization, thereby establishing an effective coupling layer between the inorganic particles and the organic system. The "interface transition layer" enhances wettability and compatibility and reduces the tendency for particle aggregation. Furthermore, the carboxyl-containing polyacrylate polymer brush layer forms a steric barrier on the particle surface in a "chain segment extension" manner. It can also enhance the electrostatic repulsion and solvation stability of particles in aqueous or polar media through the hydrophilic / ionization properties of carboxyl groups, thereby improving dispersion stability and resistance to sedimentation and re-aggregation during use. This makes the antibacterial active sites more stably exposed and is conducive to obtaining a longer-lasting antibacterial effect and better processing compatibility.

[0024] Secondly, the present invention also provides a preparation process for the rare earth composite antibacterial material, comprising the following steps: S1. Prepare zinc salt precursor solution; S2. The zinc salt precursor solution is atomized and then subjected to spray pyrolysis and / or aerosol reaction in a thermal field to obtain spherical nano zinc oxide substrate particles. S3. The spherical nano zinc oxide substrate particles are dispersed in a liquid medium, and an interface anchoring layer precursor is added for pre-anchoring treatment. The interface anchoring layer precursor is selected from one or more of condensed phosphates and their salts, phytates, phosphonates, and coordination molecules containing catechol groups. S4. Add rare earth salt precursor to the dispersion system after S3 treatment, so that rare earth ions are adsorbed and enriched on the surface and / or near the surface of the spherical nano zinc oxide substrate particles. S5. Alkali deposition is performed on the S4 system to form a rare earth deposition precursor layer on the surface of the spherical nano zinc oxide substrate particles. S6. The product of S5 is subjected to heat treatment at 300-650℃ to transform the rare earth deposition precursor layer into rare earth oxide nanodomains. S7. The product after S6 is subjected to surface compatibility treatment to form a surface compatibility layer, thereby obtaining rare earth composite antibacterial material.

[0025] Preferably, the preparation process further satisfies at least one of the following: 1) The S3 includes sequentially adding condensed phosphate and its salt to form an inorganic anchoring inner layer, and adding a coordinating molecule containing catechol group and / or phosphonate to form an organic coordinating outer layer, so as to form a double anchoring layer structure; 2) Before step S7, perform porous silica coating and / or organosilicon network coating to form a confined coating layer; 3) When the rare earth oxide is CeO2 and CeO needs to be formed 2-x Then, after step S6, a heat treatment is performed at 200-450°C in an inert and / or reducing atmosphere to convert CeO2 into CeO. 2-x , where x is 0.01-0.20.

[0026] The rare earth composite antibacterial material and its preparation process provided by this invention have at least the following beneficial effects: (1) The present invention constructs rare earth oxide nanodomains on the surface and / or near the surface of spherical nano zinc oxide substrate particles, and sets an interface anchoring layer between the rare earth oxide nanodomains and the spherical nano zinc oxide substrate particles, and coats the surface compatibility layer on the outer surface of the composite particles, so that the rare earth active sites can be stably fixed and effectively exposed, reducing particle agglomeration and active site deactivation, improving the dispersion stability and antibacterial durability of the material, thereby achieving a stable antibacterial effect under low addition conditions and taking into account processing compatibility.

[0027] (2) This invention addresses the particle size and sphericity of spherical zinc oxide nano-substrate particles, the particle size and discrete distribution morphology of rare earth oxide nanodomains, the composition and double anchoring layer structure of the interface anchoring layer, the external protective effect of the confined coating layer, and CeO 2-x Synergistic optimization of defect site regulation and interfacial transition effect of surface compatibility layer can enhance the interfacial bonding stability and dispersion stability of composite particles in mixed shear, washing or complex media environment, reduce the risk of migration, shedding and performance degradation of active components, and thus further improve the stability and applicability of antibacterial performance.

[0028] (3) In terms of preparation process, the present invention obtains spherical nano zinc oxide substrate particles by atomization pyrolysis and / or aerosol reaction, and constructs rare earth oxide nano domains and interface anchoring layer by combining pre-anchoring treatment, rare earth precursor adsorption deposition and heat treatment conversion, and then forms surface compatibility layer by surface compatibility treatment. The process route is clear and the key steps are controllable, which facilitates continuous and large-scale preparation, thereby helping to stably obtain rare earth composite antibacterial materials with controlled morphology and interface structure. Attached Figure Description

[0029] Figure 1 SEM image of the rare earth composite antibacterial material provided by this invention; Figure 2 The image shows a physical product of the rare earth composite antibacterial material provided by this invention. Detailed Implementation

[0030] To better understand the above technical solutions, a detailed description of the specific implementation methods will be provided below. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0031] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0032] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0033] like Figure 1 , Figure 2As shown, this invention provides a rare earth composite antibacterial material, preferably in powder form with composite particles as the main component. The composite particles consist of spherical nano-zinc oxide substrate particles as a supporting framework, with rare earth oxide nanodomains constructed on their surface and / or near-surface. An interface anchoring layer is provided between the rare earth oxide nanodomains and the spherical nano-zinc oxide substrate particles. A surface compatibility layer is coated on the outer surface of the composite particles. The ratio of the zinc-based matrix to the rare earth components in the powder system can be controlled within a reasonable range to balance antibacterial activity and material stability. Specifically, it includes: (1) Spherical nano-zinc oxide substrate particles. The median particle size D50 of the spherical nano-zinc oxide substrate particles can be 20-300 nm, and the sphericity is not less than 0.85; in one preferred embodiment, the spherical nano-zinc oxide substrate particles can be directly prepared by spray pyrolysis and / or aerosol reaction to obtain higher sphericity and narrower particle size distribution; in a more preferred embodiment, the spherical nano-zinc oxide substrate particles can be used as the main component of the powder, accounting for 80-95 wt% of the total powder, so as to ensure the load-bearing stability and processability of the composite particles.

[0034] In one alternative embodiment, in addition to the spherical nano zinc oxide substrate particles, the powder system may also introduce a small amount of other morphological zinc-based particles as excipients to improve packing density and dispersion behavior. The other morphological zinc-based particles may include zinc whiskers and / or flake zinc oxide and / or non-spherical nano zinc oxide.

[0035] (2) Rare earth oxide nanodomains. The rare earth oxide nanodomains are rare earth oxide particles distributed on the surface and / or near the surface of the spherical zinc oxide nanoparticles. The rare earth oxides may be selected from one or more of CeO2, La2O3, Nd2O3, Sm2O3, and Y2O3. In one preferred embodiment, the average particle size of the rare earth oxide nanodomains is 1-20 nm, and they are distributed in a discrete island or lattice pattern on the surface of the spherical zinc oxide nanoparticles. In a more preferred embodiment, the mass percentage of the rare earth component converted to rare earth oxides may be 2-20 wt%, preferably 5-15 wt%.

[0036] In one preferred embodiment, the rare earth oxide nanodomains include CeO 2-x Where x is 0.01-0.20; the CeO 2-x It can be obtained by subjecting CeO2-containing composite particles to secondary heat treatment under an inert and / or reducing atmosphere.

[0037] (3) Interface anchoring layer. The interface anchoring layer is located between the rare earth oxide nanodomain and the spherical nano zinc oxide substrate particles, and includes one or more of the following: condensed phosphate and its salt, phytate, phosphonate, and coordination molecules containing catechol groups; In one preferred embodiment, the condensed phosphate and its salts may be selected from sodium hexametaphosphate, pyrophosphate and / or polyphosphate, the phytate may be selected from sodium phytate and / or ammonium phytate, the phosphonate may be selected from hydroxyphosphonate and / or aminophosphonate, and the coordinating molecule containing catechol groups may be selected from dopamine and its derivatives, small catechol molecules and / or polymer segments containing catechol groups; In a more preferred embodiment, the amount of the interface anchoring layer introduced, based on the anchoring agent, can be 0.1-5 wt% (relative to spherical nano-zinc oxide substrate particles), to achieve stable anchoring without significantly increasing the risk of interparticle bridging. Coordination anchoring of phosphonic acids, catechols, etc., on the surface of related metal oxides is a common surface chemical pathway and can be used to improve the binding stability of ligands on oxide surfaces.

[0038] (4) Surface compatibility layer. The surface compatibility layer is coated on the outer surface of the composite particles and includes one or more of a silane coupling layer, a polysiloxane layer, and a polyacrylate polymer brush layer; in one preferred embodiment, the surface compatibility layer includes a coupling layer formed by an organosilane coupling agent, wherein the functional group of the organosilane coupling agent is selected from one or more of amino, epoxy, and methacryloxy groups; in a more preferred embodiment, the surface compatibility layer includes a carboxyl-containing polyacrylate polymer brush layer to improve the dispersion stability in aqueous systems or polar resin systems; in one optional embodiment, the powder may be further subjected to surface coating or organic modification treatment to improve its compatibility and dispersibility in polymer, resin, or coating systems.

[0039] In one preferred embodiment, the surface compatibility layer further includes a confined coating layer disposed outside the surface compatibility layer. The confined coating layer is a porous silica layer and / or an organosilicon network layer, and the thickness of the confined coating layer is 10-50 nm. In a more preferred embodiment, the porous silica layer can be formed by hydrolysis and condensation of a silicon source precursor using a sol-gel route, and the pore structure can be controlled by a template agent. The organosilicon network layer can be constructed by hydrolysis and condensation of an organosilicon precursor.

[0040] The preparation method of the above-mentioned rare earth composite antibacterial material specifically includes the following steps: S1. Prepare zinc salt precursor solution: Select zinc nitrate, zinc acetate or zinc chloride to prepare zinc salt aqueous solution or water-alcohol mixture solution, the zinc salt concentration can be 0.01-0.10 mol / L; In one preferred embodiment, in order to improve atomization stability and inhibit droplet co-aggregation, 0.01-0.1 wt% of nonionic surfactant can be added, and the solution is filtered to remove insoluble matter.

[0041] S2. Preparation of spherical nano-zinc oxide substrate particles: The zinc salt precursor solution is atomized and then subjected to spray pyrolysis and / or aerosol reaction in a thermal field to obtain spherical nano-zinc oxide substrate particles; In one preferred embodiment, droplet aerosol is obtained by ultrasonic atomization, the reaction temperature can be 400-800℃, the carrier gas is nitrogen or air, the carrier gas flow rate can be 0.5-1.0 L / min, and the product is collected by cyclone separation or filtration and dried at 60-120℃.

[0042] S3. Pre-anchoring treatment to form an interface anchoring layer: The spherical nano-zinc oxide substrate particles are dispersed in a liquid medium, and an interface anchoring layer precursor is added for pre-anchoring treatment. The interface anchoring layer precursor is selected from one or more of condensed phosphates and their salts, phytates, phosphonates, and coordination molecules containing catechol groups. In one preferred embodiment, the liquid medium is water or a water-alcohol mixture with a solid content of 1-20 wt%. After stirring or ultrasonic dispersion for 10-30 min, an anchoring agent is added and stirring is continued for 20-120 min. In a more preferred embodiment, when a double anchoring layer structure is required, S3 includes sequentially adding condensed phosphates and their salts to form an inorganic anchoring inner layer, and adding coordination molecules containing catechol groups and / or phosphonates to form an organic coordination outer layer.

[0043] S4. Constructing a rare earth adsorption enrichment layer: Add a rare earth salt precursor to the dispersion system treated in S3, so that rare earth ions are adsorbed and enriched on the surface and / or near-surface layer of the spherical nano zinc oxide substrate particles; in one preferred embodiment, the rare earth salt precursor is selected from one or more of cerium nitrate, lanthanum nitrate, neodymium nitrate, samarium nitrate or yttrium nitrate, the concentration of rare earth salt is 0.001-0.05 mol / L, the pH of the system is controlled at 3-6 to avoid spontaneous precipitation in the solution, and the adsorption time is 30-180 min.

[0044] S5. Alkali deposition to form a rare earth deposition precursor layer: Alkali deposition is performed on the S4 system to form a rare earth deposition precursor layer on the surface of the spherical nano zinc oxide substrate particles. In one preferred embodiment, the alkali source is ammonia, carbonate or sodium hydroxide solution. The pH of the system is adjusted to 8-10 by dripping and kept at 30-70℃ for 30-180 min. After deposition, solid-liquid separation is performed and the filtrate is washed with deionized water until the conductivity of the filtrate is stable.

[0045] S6. Heat treatment to form rare earth oxide nanodomains: The product of S5 is heat-treated at 300-650℃ to transform the rare earth deposition precursor layer into rare earth oxide nanodomains; in one preferred embodiment, the heating rate is 2-10℃ / min, the holding time is 0.5-4 h, and after cooling, depolymerization and sieving are performed to obtain powder with good flowability; in a more preferred embodiment, when the rare earth oxide is CeO2 and CeO is to be formed... 2-x Then, after step S6, a secondary heat treatment is performed at 200-450°C for 0.5-4 h in an inert and / or reducing atmosphere.

[0046] S7. Surface compatibility treatment to form a surface compatibility layer: The product after S6 is subjected to surface compatibility treatment to form a surface compatibility layer, thereby obtaining a rare earth composite antibacterial material. In one preferred embodiment, when a silane coupling layer is used, aminosilane, epoxysilane, or methacryloyloxysilane is pre-hydrolyzed in an aqueous alcohol system for 10-60 min and then added to a powder dispersion system. The mixture is reacted at 20-70°C for 0.5-4 h, followed by solid-liquid separation, washing, and drying at 60-120°C. In a more preferred embodiment, when a carboxyl-containing polyacrylate polymer brush layer is used, polyacrylate or polyacrylate dispersant can be added to the aqueous phase and the pH can be adjusted to 7-10 to form a stable adsorption layer or graft layer on the particle surface of the polymer chain, followed by curing and drying.

[0047] In one alternative embodiment, when it is necessary to form a confined coating layer, porous silica coating and / or organosilicon network coating are performed before step S7; specifically, a silicon source precursor such as tetraethoxysilane can be added to the powder dispersion system, and a silica layer can be formed by hydrolysis and condensation under alkaline catalysis. If necessary, a surfactant template can be introduced to obtain a porous structure, and then the powder is washed and dried to obtain a coated powder with a shell thickness of 10-50 nm. Example 1:

[0048] This embodiment provides a rare earth composite antibacterial material, the raw materials of which include: 100.0 g of spherical zinc oxide nanoparticles as substrate; 10.0 g of rare earth oxides (converted to oxides) corresponding to the rare earth oxide nanodomains, including 8.0 g of CeO2 and 2.0 g of La2O3; 1.2 g of interface anchoring layer precursor (dry basis), including 0.7 g of sodium hexametaphosphate and 0.5 g of dopamine; 1.5 g of surface compatibility layer precursor (dry basis), including 0.5 g of aminopropyltriethoxysilane and 1.0 g of sodium polyacrylate.

[0049] The above-mentioned rare earth composite antibacterial material is prepared by the following method, with the following steps: S1. Prepare zinc salt precursor solution: Weigh 365.6 g of zinc nitrate hexahydrate, dissolve it in deionized water, and make up to 2.5 L to obtain zinc salt precursor solution; filter the solution for later use.

[0050] S2. Preparation of spherical nano-zinc oxide substrate particles: The zinc salt precursor solution obtained in S1 was atomized by ultrasonic atomization (atomization frequency 1.7 MHz). Nitrogen gas was used as the carrier gas (flow rate 5.0 L / min) to send the aerosol into a tubular hot field for spray pyrolysis. The hot field temperature was set to 650℃, and spherical nano-zinc oxide substrate particles were collected. The obtained powder was dried at 80℃ for 2 h.

[0051] S3. Pre-anchoring treatment: 100.0 g of spherical nano-zinc oxide substrate particles obtained in S2 were dispersed in 2.0 L of a mixed medium of ethanol and water with a volume ratio of 80:20, stirred and ultrasonically dispersed for 10 min; 0.7 g of sodium hexametaphosphate was added to the dispersion system and stirred for 60 min; then 0.5 g of dopamine was added, the pH of the system was adjusted to 8.5, and the system was stirred and reacted at 40℃ for 2 h to obtain the dispersion system after pre-anchoring treatment.

[0052] S4. Rare Earth Salt Adsorption and Enrichment: Weigh 20.2 g of cerium nitrate hexahydrate and 5.3 g of lanthanum nitrate hexahydrate, dissolve them in 500 mL of deionized water to obtain a rare earth salt precursor solution; add the rare earth salt precursor solution to the S3 dispersion system, adjust the pH of the system to 4.5 and stir at 40℃ for 60 min to allow rare earth ions to be adsorbed and enriched on the surface and / or near the surface of the spherical nano zinc oxide substrate particles.

[0053] S5, Alkali deposition: Add 12.0 g of urea to the S4 system and keep it at 90℃ for 2 h to carry out slow-release alkali deposition; after the deposition is completed, the system is separated into solid and liquid, and the obtained solid is washed three times with deionized water and dried at 80℃ for 2 h.

[0054] S6. Heat treatment conversion: The dry solid obtained in S5 is placed in a muffle furnace and heated to 500℃ at 5℃ / min and held for 2h. After natural cooling, a composite powder containing rare earth oxide nanodomains is obtained.

[0055] S7. Surface compatibility treatment: The composite powder obtained in S6 was dispersed in 1.0 L of a mixed medium of ethanol and water in a volume ratio of 95:5. 0.5 g of aminopropyltriethoxysilane was added, and the mixture was stirred at 50 °C for 2 h. Subsequently, 1.0 g of sodium polyacrylate was added, and the pH of the system was adjusted to 8.0. The mixture was stirred for another 60 min. After solid-liquid separation, the mixture was washed once with ethanol and once with deionized water, and then dried at 80 °C for 2 h to obtain the rare earth composite antibacterial material. Example 2:

[0056] The difference between this embodiment and Example 1 is that: in S1, the amount of zinc nitrate hexahydrate is adjusted to 146.2 g and the volume is adjusted to 2.0 L; in S2, the spray pyrolysis temperature is adjusted to 550℃ and the carrier gas flow rate is adjusted to 6.0 L / min, while the remaining steps remain the same. Example 3:

[0057] The difference between this embodiment and Example 1 is that: in S1, the amount of zinc nitrate hexahydrate is adjusted to 584.9 g and the volume is adjusted to 2.0 L; in S2, the spray pyrolysis temperature is adjusted to 750℃ and the carrier gas flow rate is adjusted to 4.0 L / min, while the remaining steps remain the same. Example 4:

[0058] The difference between this embodiment and Embodiment 1 is that: the total amount of rare earth oxides in the material composition is adjusted to 2.0 g, and only CeO2 2.0 g is used; the amount of cerium nitrate hexahydrate in S4 is adjusted to 5.1 g; the total amount of the interface anchoring layer precursor is adjusted to 0.2 g (sodium hexametaphosphate 0.15 g, dopamine 0.05 g), and the rest remain the same. Example 5:

[0059] The difference between this embodiment and Embodiment 1 is as follows: the total amount of rare earth oxides in the material composition is adjusted to 20.0 g, including 16.0 g of CeO2 and 4.0 g of Nd2O3; the amount of cerium nitrate hexahydrate in S4 is adjusted to 40.4 g, and the amount of neodymium nitrate hexahydrate is adjusted to 10.4 g; the total amount of the interface anchoring layer precursor is adjusted to 5.0 g (sodium hexametaphosphate 3.0 g and dopamine 2.0 g), while the rest remain the same. Example 6:

[0060] The difference between this embodiment and Example 1 is that: the total amount of rare earth oxides in the material composition is still 10.0 g, but it is adjusted to 5.0 g of La2O3 and 5.0 g of Y2O3; S4 is changed to add 13.3 g of lanthanum nitrate hexahydrate and 15.9 g of yttrium nitrate hexahydrate; the amount of sodium polyacrylate in S7 is adjusted to 8.0 g and no silane coupling agent is added, while the rest remain the same. Example 7:

[0061] The difference between this embodiment and embodiment 1 is that: in S5, the amount of urea is adjusted to 18.0 g and the deposition holding time is adjusted to 4 h; in S6, the heat treatment temperature is adjusted to 650℃ and the holding time is 3 h, while the rest remain the same. Example 8:

[0062] The difference between this embodiment and Example 1 is that: the precursor of the interface anchoring layer in S3 is changed to 1.2 g of sodium phytate, and sodium hexametaphosphate and dopamine are not added; the pH of the reaction in S3 is adjusted to 7.5 and the reaction time is adjusted to 3 h, while the rest remain the same. Example 9:

[0063] The difference between this embodiment and Example 1 is that the precursor of the interface anchoring layer in S3 is changed to 0.8 g of hydroxyethylidene diphosphonic acid and 0.4 g of sodium pyrophosphate; the pH of the reaction in S3 is adjusted to 5.5, the reaction temperature is adjusted to 30℃, and the reaction time is adjusted to 2 h, while the rest remain the same. Example 10:

[0064] The difference between this embodiment and Example 1 is that S3 is carried out in stages. First, 0.7 g of sodium hexametaphosphate is added and stirred for 60 min to form an inorganic anchoring inner layer. Then, 0.5 g of dopamine is added and reacted at pH 8.5 and 40℃ for 2 h to form an organic coordination outer layer. The rest remains the same. Example 11:

[0065] The difference between this embodiment and Example 1 is that in S7, aminopropyltriethoxysilane is replaced with 0.5 g of γ-glycidyl ether propyltrimethoxysilane, while the rest remains the same. Example 12:

[0066] The difference between this embodiment and Example 1 is that in S7, aminopropyltriethoxysilane is replaced with 0.5 g of methacryloyloxypropyltrimethoxysilane, while the rest remains the same. Example 13:

[0067] The difference between this embodiment and Example 1 is that a coating step is added after S6 and before S7: the composite powder obtained in S6 is dispersed in 1.0 L of a mixed medium of ethanol and water in a volume ratio of 70:30, 2.0 g of hexadecyltrimethylammonium bromide is added and stirred for 30 min; then 12.0 g of tetraethyl orthosilicate is added and 5.0 mL of ammonia is added dropwise, and the mixture is stirred at 30 °C for 4 h; after solid-liquid separation, the mixture is washed twice with ethanol and dried at 80 °C for 2 h, and then surface compatibility treatment is performed according to S7 of Example 1, while the rest remains the same. Example 14:

[0068] The difference between this embodiment and Example 1 is that a coating step is added after S6 and before S7: the composite powder obtained in S6 is dispersed in 1.0 L of a mixed medium of ethanol and water in a volume ratio of 80:20, 15.0 g of methyltrimethoxysilane is added and 0.5 mL of acetic acid is added dropwise as a catalyst, and the mixture is stirred at 40 °C for 6 h; after solid-liquid separation, the powder is washed twice with ethanol and dried at 80 °C for 2 h, and then surface compatibility treatment is performed according to S7 of Example 1, while the rest remains the same. Example 15:

[0069] The difference between this embodiment and embodiment 1 is that a secondary heat treatment step is added after S6: the powder obtained in S6 is placed in a tube furnace and a mixture of hydrogen and nitrogen with a volume fraction of 5% (total flow rate 1.0 L / min) is introduced, the temperature is raised to 350℃ at 5℃ / min and held for 2 h, and after cooling, the surface compatibility treatment is carried out according to S7 of embodiment 1, and the rest remains the same. Example 16:

[0070] The difference between this embodiment and embodiment 1 is that: S3 adopts the double anchoring layer segmentation method of embodiment 10; after S6, it is first reduced at 350°C according to embodiment 15, then a porous silicon dioxide layer is formed according to embodiment 13, and finally surface compatibility treatment is performed in S7, while the rest remains the same.

[0071] Comparative Example 1 The difference between this comparative example and Example 1 is that the S3-S7 treatment is not performed; only the spherical nano zinc oxide substrate particles are prepared and dried according to the S1-S2 of Example 1, while the rest remain the same.

[0072] Comparative Example 2 The difference between this comparative example and Example 1 is that 100.0 g of spherical nano zinc oxide substrate particles and 10.0 g of CeO2 powder are directly dry mixed for 30 min, without the adsorption enrichment, deposition and thermal treatment conversion steps of S3-S6, and without the surface compatibility treatment of S7, while the rest remain the same.

[0073] Comparative Example 3 The difference between this comparative example and Example 1 is that the pre-anchoring treatment in S3 is omitted; S4-S6 are directly carried out in the dispersion system obtained in S2 to form rare earth oxide deposition conversion products, followed by S7 as in Example 1, while the rest remain the same.

[0074] Comparative Example 4 The difference between this comparative example and Example 1 is that S1-S6 are performed the same as in Example 1, but the surface compatibility treatment in S7 is omitted, while the rest remain the same.

[0075] Comparative Example 5 The difference between this comparative example and Example 1 is that the pre-anchoring process S3 is omitted; S4-S6 are the same as in Example 1, followed by surface compatibility processing S7, and the rest remain the same.

[0076] Comparative Example 6 The difference between this comparative example and Example 1 is that: S2 does not use spray pyrolysis; instead, zinc acetate solution is added dropwise to sodium hydroxide solution at 60°C to carry out precipitation reaction and age for 2 h, after solid-liquid separation, washing and drying, and then heat-preserving at 500°C for 2 h to obtain non-spherical zinc oxide powder; then it is processed according to S3-S7 of Example 1, and the rest remains the same.

[0077] Comparative Example 7 The difference between this comparative example and Example 1 is as follows: the concentration of the rare earth salt precursor solution in S4 is increased and the amount of rare earth salt added corresponds to a total amount of rare earth oxides of 30.0 g; S5 is changed to rapidly adding ammonia water at 25°C to directly adjust the pH of the system to 10.5 and maintain it for 30 min; S6 is treated by keeping it at 650°C for 3 h, and the rest remains the same.

[0078] Comparative Example 8 The difference between this comparative example and Example 1 is that, in order to obtain a higher degree of oxygen vacancies, stronger reduction treatment conditions are used after S6: the product is placed in a reducing atmosphere in which hydrogen gas accounts for 10% and the remainder is nitrogen gas, and heat-treated at 500°C for 4 h to control CeO 2-x x is 0.28.

[0079] Test methods 1. Antibacterial rate (%): Referring to GB / T 21510-2024 "Test Methods and Evaluation of Antibacterial Properties of Nano-Inorganic Materials", Escherichia coli and Staphylococcus aureus were selected as representative bacterial species. After the sample (antibacterial powder or powder-containing product) was in contact with a bacterial suspension of a certain concentration and cultured for a specified time, the number of surviving colonies was determined by plate counting method, and the antibacterial rate was calculated according to the difference in colony count between the control group and the sample group.

[0080] 2. Antibacterial activity value R (log): Refer to ISO 22196 (equivalent method is often used for non-porous surfaces); inoculate the surface of the sample containing antibacterial material with a specified volume and concentration of bacterial solution and cover it with a thin film for constant temperature incubation. After incubation, wash off and recover the surviving bacteria and count them. The antibacterial activity value R is obtained by converting the colony count of the control sample and the sample (the comparison is more sensitive and suitable for reflecting the difference of "surface contact bactericidal / bacteriostatic").

[0081] 3. Antimicrobial durability retention rate (%): Refer to GB / T 21866-2008 (or follow the “Antibacterial Durability Test” approach of the soon-to-be-implemented GB / T 21866-2025); first subject the sample (such as film / coating or carrier product) to the specified accelerated aging or durability treatment (such as ultraviolet irradiation, heat and humidity treatment or immersion / washing cycle), and then retest the antimicrobial index according to the same antimicrobial evaluation method, and calculate the retention rate of antimicrobial rate (or R value) before and after the durability treatment.

[0082] 4. Zeta potential (mV): Refer to ISO 13099-1 "Colloidal systems—Determination of zeta potential"; disperse the antibacterial powder in a specified medium (such as water / ethanol-water) according to the fixed solids content and ultrasonically disperse until stable, measure the electrophoretic mobility and convert it to zeta potential, which is used to characterize the dispersion stability and compatibility modification effect (generally, the larger the |ze|, the better the electrostatic stability).

[0083] 5. Median particle size D50 (nm): Refer to GB / T 19077-2024 "Particle size analysis by laser diffraction"; disperse the sample in a laser diffractometer using a dry or wet method, measure the volume distribution particle size under the conditions of light shading and dispersion, and report D50 as a characterization index for particle size control and batch consistency.

[0084] Test Results The powder dispersion characterization and antibacterial rate test results of Comparative Examples 1-8 and Examples 1-16 are shown in Table 1: Table 1

[0085] The results of the surface antibacterial activity and durability tests of the carrier products of Comparative Examples 1-8 and Examples 1-16 are shown in Table 2: Table 2

[0086] Regarding the antibacterial properties of the powder, Example 1 showed antibacterial rates of 99.6% against Escherichia coli and 99.7% against Staphylococcus aureus, significantly better than Comparative Example 1 (88.2%, 90.1%) containing only spherical nano-zinc oxide and Comparative Example 2 (90.4%, 92.0%) using a physical mixture of rare earth oxides. In the comparison of key structural deficiencies, Comparative Example 3 (without an interface anchoring layer) and Comparative Example 4 (without a surface compatibility layer) showed improvements over Comparative Example 1, but their dispersion characterization and antibacterial rate were still lower than Example 1, indicating that interface stabilization and surface compatibility treatment have a significant effect on maintaining stable dispersion and effective antibacterial properties of the composite particles.

[0087] Regarding surface antibacterial activity and durability, the antibacterial activity values ​​R of Example 1 were 3.2 and 3.3, respectively, significantly higher than those of Comparative Example 1 (1.3, 1.5); and the R retention rate after 10 water washing cycles was 86%, significantly higher than that of Comparative Example 2 (48%) and Comparative Example 3 (61%), indicating that the stability of the composite structure and interface bonding helps to reduce performance degradation caused by the migration or shedding of active components. Furthermore, Example 10 (dual anchoring layer) increased the retention rate to 90%; Examples 13 and 14 (confined coating layer) reached 92% and 93%, respectively; Example 15 (CeO… 2-x The R values ​​were improved to 3.8 and 3.9 when x was 0.12; when multiple optimization combinations were superimposed (Example 16), the R values ​​reached 4.1 and 4.2 with a retention rate of 94%, demonstrating that the antibacterial activity and durability were further enhanced under the synergistic effect of interface stability, outer confinement and defect activity.

[0088] In summary, as shown in Tables 1 and 2, the rare earth composite antibacterial material of this invention exhibits significant improvements over the comparative sample in terms of antibacterial rate, surface antibacterial activity, and durability retention. Compared to the comparative sample containing only zinc oxide or a physical mixture of rare earth oxides, the antibacterial rate of the sample of this invention against representative bacteria is improved to near-complete inhibition. Furthermore, the antibacterial activity value R is significantly increased in the evaluation of non-porous surfaces of the coating, and a high proportion of antibacterial activity is maintained even after water washing. Simultaneously, the Zeta potential and particle size distribution results show that the composite particles exhibit better stability in the dispersion system, indicating that by constructing rare earth oxide nanodomains and combining them with an interface anchoring layer and a surface compatibility layer, the migration and desorption of active components and secondary particle aggregation can be effectively suppressed, thereby achieving stable antibacterial performance and simultaneous improvement in processing adaptability. Based on this, the double anchoring layer, confined coating layer, and CeO2 further enhance the antibacterial properties. 2-x The optimized schemes, such as defect control, further improve the surface antibacterial activity and durability retention rate, demonstrating the synergistic gain between interface stability, outer layer confinement and defect activity, thereby verifying that the present invention can obtain a more stable and longer-lasting comprehensive antibacterial effect within a wider parameter window.

[0089] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if these modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include these modifications and modifications.

Claims

1. A rare earth composite antibacterial material, characterized in that, include: Spherical nano-zinc oxide substrate particles, rare earth oxide nanodomains, interface anchoring layer and surface compatibility layer; The rare earth oxide nanodomains are rare earth oxide particles distributed on the surface and / or near the surface of the spherical nano zinc oxide substrate particles, and the rare earth oxides are selected from one or more of CeO2, La2O3, Nd2O3, Sm2O3, and Y2O3. The interface anchoring layer is located between the rare earth oxide nanodomain and the spherical nano zinc oxide substrate particles, and the interface anchoring layer includes one or more of the following: condensed phosphate and its salt, phytate, phosphonate, and coordination molecules containing catechol groups. The spherical zinc oxide nanoparticles, the rare earth oxide nanodomains, and the interface anchoring layer together constitute the composite particles. The surface compatibility layer is coated on the outer surface of the composite particles, and the surface compatibility layer includes one or more of the following: silane coupling layer, polysiloxane layer, and polyacrylate polymer brush layer.

2. The rare earth composite antibacterial material according to claim 1, characterized in that, The median particle size D50 of the spherical nano zinc oxide substrate particles is 20-300 nm, and the sphericity is not less than 0.

85.

3. The rare earth composite antibacterial material according to claim 1, characterized in that, The rare earth oxide nanodomains have an average particle size of 1-20 nm and are distributed in a discrete island or lattice pattern on the surface of the spherical nano zinc oxide substrate particles.

4. The rare earth composite antibacterial material according to claim 1, characterized in that, The interface anchoring layer comprises condensed phosphates and their salts and / or phytates and / or phosphonates and / or coordination molecules containing catechol groups.

5. The rare earth composite antibacterial material according to claim 1, characterized in that, The interface anchoring layer has a dual anchoring layer structure, including an inorganic anchoring inner layer and an organic coordination outer layer located outside the inorganic anchoring inner layer. The inorganic anchoring inner layer comprises one or more of condensed phosphates and their salts, and the organic coordination outer layer comprises one or more of coordination molecules containing catechol groups and / or phosphonates.

6. The rare earth composite antibacterial material according to claim 1, characterized in that, The composite particles further include a confined coating layer, which is disposed outside the surface compatibility layer. The confined coating layer is a porous silica layer and / or an organosilicon network layer, and the thickness of the confined coating layer is 10-50 nm.

7. The rare earth composite antibacterial material according to claim 1, characterized in that, The rare earth oxide nanodomains include CeO 2-x , where x is 0.01-0.

20.

8. The rare earth composite antibacterial material according to claim 1, characterized in that, The surface compatibility layer includes a coupling layer formed by an organosilane coupling agent, wherein the functional group of the organosilane coupling agent is selected from one or more of amino, epoxy, and methacryloxy groups, and / or the surface compatibility layer includes a polyacrylate polymer brush layer containing carboxyl groups.

9. A preparation process for the rare earth composite antibacterial material according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Prepare zinc salt precursor solution; S2. The zinc salt precursor solution is atomized and then subjected to spray pyrolysis and / or aerosol reaction in a thermal field to obtain spherical nano zinc oxide substrate particles. S3. The spherical nano zinc oxide substrate particles are dispersed in a liquid medium, and an interface anchoring layer precursor is added for pre-anchoring treatment. The interface anchoring layer precursor is selected from one or more of condensed phosphates and their salts, phytates, phosphonates, and coordination molecules containing catechol groups. S4. Add rare earth salt precursor to the dispersion system after S3 treatment, so that rare earth ions are adsorbed and enriched on the surface and / or near the surface of the spherical nano zinc oxide substrate particles. S5. Alkali deposition is performed on the S4 system to form a rare earth deposition precursor layer on the surface of the spherical nano zinc oxide substrate particles. S6. The product of S5 is subjected to heat treatment at 300-650℃ to transform the rare earth deposition precursor layer into rare earth oxide nanodomains. S7. The product after S6 is subjected to surface compatibility treatment to form a surface compatibility layer, thereby obtaining rare earth composite antibacterial material.

10. The preparation process according to claim 9, characterized in that, The preparation process further satisfies at least one of the following: 1) The S3 includes sequentially adding condensed phosphate and its salt to form an inorganic anchoring inner layer, and adding a coordinating molecule containing catechol group and / or phosphonate to form an organic coordinating outer layer, so as to form a double anchoring layer structure; 2) Before step S7, perform porous silica coating and / or organosilicon network coating to form a confined coating layer; 3) When the rare earth oxide is CeO2 and CeO needs to be formed 2-x Then, after step S6, a heat treatment is performed at 200-450°C in an inert and / or reducing atmosphere to convert CeO2 into CeO. 2-x , where x is 0.01-0.20.

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