Long-acting antibacterial ceramic silver-loaded material and preparation method and application thereof

Abstract

The application discloses a long-acting antibacterial ceramic silver-loaded material and a preparation method and application thereof, and belongs to the technical field of nanomaterials, and comprises the following steps: cleaning and roughening and activating a ceramic substrate; constructing an organic-inorganic hybrid molecular layer containing amino groups or mercapto groups on the surface of the pretreated ceramic substrate; immersing the pretreated ceramic substrate in a solution containing Ag + for ion exchange treatment; placing the ceramic substrate after primary silver loading in a mixed aqueous solution containing a silver source, a stabilizer and a weak reducing agent, and performing an in-situ reduction reaction under inert gas protection; and cleaning, drying and heat treating the loaded ceramic substrate to obtain the ceramic silver-loaded material. Through the construction of a surface chemical anchoring molecular layer and the adoption of a step-by-step composite silver loading process, a double silver ion release structure is established in the material, and high-strength combination of nanosilver and the ceramic substrate and rapid effect and long-term persistence of antibacterial performance are realized.

Description

Technical Field

[0001] This invention belongs to the field of nanomaterials technology, specifically relating to a long-lasting antibacterial ceramic silver-loaded material, its preparation method, and its application. Background Technology

[0002] Due to its broad-spectrum and highly efficient antibacterial properties, nano-silver has shown great application potential in fields such as medicine, water treatment, and daily-use ceramics. Loading nano-silver onto a chemically stable and mechanically strong ceramic carrier can combine the advantages of both to obtain ideal antibacterial materials.

[0003] Currently, common ceramic silver loading technologies mostly employ physical adsorption or simple immersion reduction methods. These methods have significant drawbacks: low bonding strength, with silver particles primarily undergoing physical adsorption or weak interactions with the ceramic substrate, making them prone to detachment during friction, erosion, or long-term use. This not only leads to the loss of antibacterial function but may also cause secondary pollution due to the release of silver particles; uneven distribution and easy agglomeration of silver particles, resulting in uneven distribution on the ceramic surface during loading, which reduces silver utilization (wasting resources) and affects the uniformity and reliability of antibacterial efficiency; difficulty in controlling silver release behavior, as the release kinetics (ion release rate) of loaded silver particles is often difficult to precisely control, easily leading to rapid release in the initial stage or insufficient release in the long term, failing to meet the requirements of rapid onset and long-lasting effectiveness; limitations in methods to enhance bonding, as some methods aimed at improving bonding strength (such as high-temperature sintering) can easily cause the growth and agglomeration of nano-silver particles, thereby losing their excellent antibacterial properties at the nanoscale; and some chemical modification processes may introduce toxic reagents, posing environmental and safety risks. Therefore, a method for preparing silver-loaded ceramic materials that enables nano-silver to be firmly bonded to a ceramic substrate, uniformly distributed, and with controllable release behavior is proposed. Summary of the Invention

[0004] To overcome the problems of low bonding strength, uneven distribution and easy aggregation of silver particles, and difficulty in controlling silver release behavior in the prior art, this invention provides a long-lasting antibacterial ceramic silver-loaded material and its preparation method, which enables nano-silver to be firmly bonded to the ceramic substrate, uniformly distributed, and with controllable release behavior.

[0005] The objective of this invention is achieved through the following technical solution.

[0006] In a first aspect, this application provides a method for preparing a long-lasting antibacterial ceramic silver-loaded material, comprising the following steps:

[0007] S1. Ceramic substrate pretreatment: The ceramic substrate is cleaned and roughened to obtain a clean, rough surface rich in hydroxyl groups.

[0008] S2, Silanization modification: On the surface of the pretreated ceramic substrate, an organic-inorganic hybrid molecular layer containing amino or thiol groups is constructed;

[0009] S3, Primary silver loading: Immerse the ceramic substrate treated in step S2 into an Ag-containing... + Ion exchange treatment was performed on the solution to allow Ag to... + It coordinates and chelates with the amino or thiol groups in the organic-inorganic hybrid molecular layer;

[0010] S4, Secondary Silver Loading: The ceramic substrate after step S3 is placed in a mixed aqueous solution containing a silver source, stabilizer, and weak reducing agent, and an in-situ reduction reaction is carried out under inert gas protection, causing some Ag to be reduced. + The ceramic substrate surface and pores are reduced to nano-silver particles and deposited.

[0011] S5. Post-processing: The loaded ceramic substrate is cleaned, dried and heat-treated to obtain the ceramic silver-loaded material.

[0012] Furthermore, in step S1, the roughening and activation treatment is performed by treating with a piranha solution at 60~100℃ for 0.5~2 hours.

[0013] Further, in step S2, the organic-inorganic hybrid molecular layer is constructed by modification with a silane coupling agent; the silane coupling agent is 3-aminopropyltriethoxysilane or 3-mercaptopropyltrimethoxysilane.

[0014] Further, in step S3, the Ag-containing... + The solution is silver nitrate solution or silver ammonia solution; the ion exchange treatment is performed at a temperature of 60~80℃ for 4~12 hours.

[0015] Further, in step S4, the silver source is silver nitrate, the stabilizer is polyvinylpyrrolidone, and the weak reducing agent is sodium citrate; the Ag in the mixed aqueous solution... + The mass ratio of polyvinylpyrrolidone to polyvinylpyrrolidone is (0.001~0.01):1.

[0016] Furthermore, in step S4, the in-situ reduction reaction is carried out at a temperature of 70~90℃ for 2~6 hours under nitrogen or argon protection.

[0017] Furthermore, in step S4, the heat treatment is carried out under an inert atmosphere or vacuum, at a temperature of 200~300℃, for a time of 0.5~2 hours.

[0018] Secondly, this application provides a long-lasting antibacterial ceramic silver-loaded material prepared according to the above preparation method.

[0019] Furthermore, Ag chelated through coordination is present simultaneously on the surface and near the surface of the material. + And through in-situ reduction deposition of silver nanoparticles, a rapid release zone and a slow release zone of silver ions are formed.

[0020] Thirdly, this application also provides an antibacterial article comprising the ceramic silver-loaded material as described above.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) This invention achieves strong chemical bonding between silver species and the substrate through silanization modification and stepwise chemical loading, fundamentally solving the problems of weak binding force and easy silver detachment in traditional physical adsorption methods. The molecular layer provides uniform active sites, primary ion exchange ensures the initial uniform adsorption of silver, and secondary in-situ reduction allows for the controllable growth of silver nanoparticles near the adsorbed sites, avoiding agglomeration and ensuring uniform distribution of silver particles.

[0023] (2) By using primary silver-loaded ion exchange and secondary silver-loaded in-situ reduction processes, a dual silver ion release system combining rapid release and slow release was constructed, thus taking into account both rapid antibacterial effect and long-lasting effect.

[0024] (3) The entire preparation process does not require the use of highly toxic reagents. By adjusting parameters such as solution concentration, reaction temperature and time, the loading, particle size and distribution of silver can be easily controlled. The process has good repeatability and is suitable for large-scale production. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.

[0026] This embodiment establishes a dual silver ion release structure in the material through the construction of a surface chemically anchored molecular layer and the use of a stepwise composite silver loading process. This achieves a high-strength bond between the nano-silver and the ceramic substrate, as well as rapid onset and long-lasting antibacterial properties. The specific implementation method is as follows:

[0027] In a first aspect, this embodiment provides a method for preparing a long-lasting antibacterial ceramic silver-supported material, comprising the following steps:

[0028] S1. Ceramic substrate pretreatment: The ceramic substrate is cleaned and roughened to obtain a clean, rough surface rich in hydroxyl groups.

[0029] S2, Silanization modification: On the surface of the pretreated ceramic substrate, an organic-inorganic hybrid molecular layer containing amino or thiol groups is constructed;

[0030] S3, Primary silver loading: Immerse the ceramic substrate treated in step S2 into an Ag-containing... + Ion exchange treatment was performed on the solution to allow Ag to... + Ag undergoes coordination chelation with the amino or thiol groups in the organic-inorganic hybrid molecular layer, during which time Ag... + It undergoes strong coordination chelation with the amino or thiol groups in the molecular layer and is firmly adsorbed on the ceramic surface and near the surface pore area, forming initial silver storage sites.

[0031] S4, Secondary Silver Loading: The ceramic substrate after step S3 is placed in a mixed aqueous solution containing a silver source, stabilizer, and weak reducing agent, and an in-situ reduction reaction is carried out under inert gas protection, causing some Ag to be reduced. + The ceramic substrate surface and pores are reduced to nano-silver particles and deposited.

[0032] S5. Post-processing: The loaded ceramic substrate is cleaned, dried and heat-treated to obtain the ceramic silver-loaded material.

[0033] By constructing molecular layers containing active groups and employing a stepwise loading strategy, silver species (Ag) can be fundamentally controlled. + The physical adsorption of silver particles (including nano-Ag) onto the ceramic substrate is transformed into strong chemical bonding (coordination and chelation), thereby synergistically solving the three core problems mentioned in the background technology: low binding strength of silver particles, easy detachment, uneven distribution, and uncontrollable release behavior, achieving a balance between high binding strength and long-lasting antibacterial effect.

[0034] In a preferred embodiment, in step S1, the roughening and activation treatment is performed by treating with a piranha solution at 60-100°C for 0.5-2 hours. The piranha solution is, for example, a mixture of concentrated sulfuric acid and 30% hydrogen peroxide solution in a 7:3 ratio.

[0035] Here, the specific conditions for roughening and activation using piranha solution are clarified. This strong oxidizing treatment can efficiently remove organic impurities and create abundant hydroxyl groups on the ceramic surface, greatly improving surface energy and reactivity. This provides the necessary prerequisite for the subsequent strong bonding of silane coupling agents and ensures the stability and uniformity of the molecular layer structure.

[0036] In a preferred embodiment, the organic-inorganic hybrid molecular layer is constructed by modification with a silane coupling agent; the silane coupling agent is 3-aminopropyltriethoxysilane (APTES) or 3-mercaptopropyltrimethoxysilane (MPTMS).

[0037] The silanization modification method involves constructing a molecular layer using a specific silane coupling agent (APTES or MPTMS). A ceramic sheet is immersed in an anhydrous ethanol solution containing 3-aminopropyltriethoxysilane, reacted in a water bath, rinsed several times with ethanol, and then cured in an oven to obtain a ceramic substrate rich in amino groups. One end of the coupling agent hydrolyzes and condenses with the hydroxyl groups on the ceramic surface to form covalent bonds, while the other end provides amino or thiol active groups. This molecular layer, acting as a "molecular bridge," provides precise, uniform, and robust sites for the subsequent strong chemical anchoring of silver ions, forming a key chemical basis for achieving high binding strength.

[0038] In a preferred embodiment, in step S3, the Ag-containing... + The solution is silver nitrate solution or silver ammonia solution; the ion exchange treatment is performed at a temperature of 60~80℃ for 4~12 hours.

[0039] Using silver nitrate or silver ammonia solution as the silver source, and proceeding at optimal temperature and time, ensured the quality of Ag. + This allows for sufficient and uniform coordination with amino / thiol groups in the molecular layer. This step forms the first rapid release silver source and initially and firmly fixes the silver onto the substrate, laying the spatial distribution foundation for subsequent in-situ reduction.

[0040] In a preferred embodiment, in step S4, the silver source is silver nitrate, the stabilizer is polyvinylpyrrolidone, and the weak reducing agent is sodium citrate; the Ag in the mixed aqueous solution... + The mass ratio of polyvinylpyrrolidone (PVP) to polyvinylpyrrolidone (0.001~0.01):1.

[0041] Here, Ag is specified. + The mass ratio of PVP (0.001~0.01):1 ensures that PVP effectively encapsulates and stabilizes the newly generated silver nanonuclei, preventing them from excessively agglomerating or growing too quickly. This results in the in-situ generation of uniformly distributed, size-controllable silver nanoparticles as a second, slowly released silver source on the ceramic surface and at the pores.

[0042] In a preferred embodiment, in step S4, the in-situ reduction reaction is carried out at a temperature of 70-90°C for 2-6 hours, and the reaction is conducted under nitrogen or argon protection.

[0043] Here, the protection of inert gas (N2 or Ar) can prevent the nano-silver from being oxidized; the temperature range of 70~90℃ can ensure that the reduction reaction proceeds at a reasonable rate, while avoiding excessive temperature that would cause the nano-silver particles to rapidly aggregate and coarsen or decompose into molecular layers, thus ensuring the stability of the nanoscale effect and loading process of the nano-silver.

[0044] In a preferred embodiment, in step S4, the heat treatment is carried out under an inert atmosphere or vacuum, at a temperature of 200~300℃, for a time of 0.5~2 hours.

[0045] Low-temperature heat treatment at 200-300℃ under an inert atmosphere or vacuum can further promote the chemical bonding between the molecular layer and the ceramic substrate, as well as between the silver species and the molecular layer (such as further condensation and coordination strengthening), thereby significantly enhancing the bonding strength. At the same time, it avoids the loss of activity caused by the sintering and growth of nano-silver due to excessively high temperature, achieving the best balance between improving stability and maintaining antibacterial activity.

[0046] Secondly, this embodiment provides a high-bonding-strength, long-lasting antibacterial ceramic silver-loaded material prepared according to the above preparation method.

[0047] In a preferred embodiment, Ag chelated through coordination is present simultaneously on the surface and near the surface of the material. + And through in-situ reduction deposition of silver nanoparticles, a rapid release zone and a slow release zone of silver ions are formed.

[0048] The silver nanoparticles are firmly anchored to the modified molecular layer on the ceramic substrate surface through chemical coordination bonds and possible chemical bonding, exhibiting high bonding strength and resistance to detachment. Simultaneously, a unique "dual silver source" structure is formed on the material surface and near-surface region, where Ag is fixed through coordination chelation. + This forms a region capable of rapidly releasing silver ions, enabling rapid antibacterial action; while the in-situ reduced and deposited nano-silver particles constitute a stable and long-lasting slow-release region of silver ions, ensuring long-lasting antibacterial performance.

[0049] Thirdly, this embodiment also provides an antibacterial product comprising the ceramic silver-loaded material as described above.

[0050] Example 1

[0051] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0052] S1. Pretreatment: The alumina ceramic sheet is ultrasonically cleaned in acetone, ethanol, and deionized water for 20 minutes each. Then it is immersed in freshly prepared piranha solution (V concentrated sulfuric acid:V 30% hydrogen peroxide = 7:3) and treated at 80°C for 1 hour. After removal, it is washed with a large amount of deionized water and the surface is dried with nitrogen.

[0053] S2. Silanization Modification: The cleaned ceramic sheet was immersed in an anhydrous ethanol solution containing 2% (v / v) 3-aminopropyltriethoxysilane (APTES) and reacted in a water bath at 60°C for 3 hours. After removal, it was rinsed several times with ethanol and cured in an oven at 120°C for 1 hour to obtain a ceramic substrate with an amino-rich surface.

[0054] S3, Primary Silver Loading: The modified ceramic sheet is immersed in 200 ml of 0.2 mol / L silver nitrate solution and stirred at 70℃ for 8 hours to allow silver ions to fully coordinate with the amino groups on the surface.

[0055] S4, Secondary Silver Loading: Remove the ceramic sheet, rinse it gently with deionized water, and quickly transfer it to 200 mL of nano-silver in-situ generation solution containing 6.35 g PVP (K30), 0.1 g AgNO3 and 0.1 g sodium citrate. Purge the solution with nitrogen gas for 30 minutes to remove dissolved oxygen. Then, under continuous nitrogen protection, raise the temperature to 80 °C and stir magnetically for 4 hours.

[0056] S5. Post-treatment: After the reaction, thoroughly wash the sample with deionized water until the washing solution is colorless and clear. Place the sample in a vacuum drying oven at 60℃ to dry. Finally, heat-treat the dried sample at 250℃ for 1 hour under argon protection. After natural cooling, the final silver-loaded antibacterial ceramic sheet product is obtained.

[0057] Example 2

[0058] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0059] S1. Pretreatment: Weigh 10g of silicon nitride ceramic flakes and ultrasonically clean them sequentially with acetone, ethanol, and deionized water for 30 minutes each, then filter to separate them. Immerse the cleaned zeolite in freshly prepared piranha solution (V concentrated sulfuric acid:V 30% hydrogen peroxide = 7:3) and stir at 70℃ for 1.5 hours. After treatment, wash repeatedly with deionized water until neutral, and dry in an oven at 80℃ for later use.

[0060] S2. Silanization Modification: Pretreated silicon nitride ceramic particles were dispersed in an ethanol-water mixture (ethanol:water = 9:1) containing 1.5% (v / v) 3-mercaptopropyltrimethoxysilane (MPTMS), and the mixture was shaken and reacted in a 50°C water bath for 4 hours. After the reaction, the particles were washed with ethanol by centrifugation and cured in a 100°C oven for 2 hours to obtain a modified silicon nitride ceramic support with a surface rich in mercapto groups.

[0061] S3, Primary Silver Loading: Modified zeolite particles are immersed in a 0.1 mol / L silver ammonia solution and stirred in a 75°C water bath in the dark for 6 hours to allow Ag to exchange.+ It is fully coordinated with the thiol group.

[0062] S4, Secondary Silver Loading: The ion-exchange-completed silicon nitride ceramic particles were centrifuged, quickly rinsed with deionized water, and then redispersed in 150 ml of a pre-prepared in-situ silver nanoparticle generation solution containing 0.2 g AgNO3, 18.14 g PVP (K90), and 0.05 g sodium citrate. Argon gas was continuously purged into the system for 40 minutes to remove oxygen, and then the temperature was raised to 85 °C under argon protection, and the mixture was refluxed and stirred for 3 hours.

[0063] S5. Post-processing: After the reaction, the solid product was collected by centrifugation and washed several times alternately with deionized water and ethanol until the conductivity of the supernatant remained essentially unchanged. The product was then dried in a vacuum drying oven at 80℃ for 12 hours. Finally, it was heat-treated at 220℃ for 1.5 hours under vacuum (<100Pa) to obtain the final silver-loaded antibacterial silicon nitride ceramic particles.

[0064] Example 3

[0065] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0066] S1. Pretreatment: Place the silica ceramic microspheres in a 1 mol / L NaOH solution, ultrasonically clean for 15 minutes, and then wash with deionized water. Subsequently, immerse them in a piranha solution (V concentrated sulfuric acid:V 30% hydrogen peroxide = 7:3) and treat at 90℃ for 40 hours. After removal, wash with a large amount of deionized water and dry with nitrogen.

[0067] S2. Silanization modification: Ceramic microspheres were immersed in a toluene solution containing 3% APTES and refluxed at 80°C for 2 hours. After removal, they were rinsed sequentially with toluene and ethanol, and then cured in an oven at 110°C for 45 minutes to obtain a ceramic substrate with an amino-rich surface.

[0068] S3, Primary Silver Loading: The modified ceramic microspheres were immersed in 200 ml of 0.3 mol / L silver nitrate solution and shaken at 65°C in the dark for 4 hours to allow silver ions to fully coordinate with the amino groups on the surface.

[0069] S4, Secondary Silver Loading: Take out the ceramic microspheres, rinse them slightly with deionized water, and quickly put them into 500 mL of nano-silver in-situ generation solution containing 0.1 g AgNO3, 12.7 g PVP and 0.1 g sodium citrate. After purging the solution with nitrogen for 20 minutes, raise the temperature to 70 °C under nitrogen protection and stir vigorously for 2 hours.

[0070] S5. Post-treatment: After cooling, the reaction solution was filtered, and the filter cake was washed with deionized water until the washing solution was colorless and clear. The product was then dried in a forced-air environment at 70°C for 6 hours. Subsequently, it was heat-treated at 200°C for 2 hours under nitrogen protection to obtain silver-loaded ceramic microspheres.

[0071] Example 4

[0072] A method for preparing a high-performance, long-lasting antibacterial ceramic silver-supported material includes the following steps:

[0073] S1. Pretreatment: The yttrium-stabilized zirconia (YSZ) ceramic sheet was ultrasonically cleaned for 20 minutes each in acetone, ethanol, and deionized water. Then it was immersed in a piranha solution (V concentrated sulfuric acid:V 30% hydrogen peroxide = 7:3) and treated at 80°C for 1 hour, followed by cleaning and drying.

[0074] S2. Silanization modification: The cleaned ceramic sheet was immersed in an anhydrous ethanol solution containing 2% (v / v) 3-aminopropyltriethoxysilane and reacted in a 60°C water bath for 3 hours. After removal, it was rinsed several times with ethanol and cured in a 120°C oven for 1 hour to obtain a ceramic substrate with an amino-rich surface.

[0075] S3, Primary Silver Loading: The modified zirconia ceramic sheet is immersed in 200 ml of 0.15 mol / L silver nitrate solution and stirred at 70℃ for 8 hours to allow silver ions to fully coordinate with the amino groups on the surface.

[0076] S4, Secondary silver loading: Remove the ceramic sheet that has completed primary silver loading, rinse it, and quickly transfer it to 800mL of nano-silver in-situ generation solution containing 0.1gAgNO3, 21.17gPVP(K30) and 0.1gascorbic acid. After purging with argon gas for 30 minutes to remove oxygen, react at 70℃ for 5 hours under argon protection.

[0077] S5. Post-treatment: Wash thoroughly with deionized water until the washing solution is colorless and clear, then place the sample in a vacuum dryer at 60℃. Finally, heat-treat at 280℃ for 45 hours under argon protection to obtain zirconia-based silver-loaded antibacterial ceramic sheets.

[0078] Example 5

[0079] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0080] S1. Pretreatment: The alumina ceramic sheet is ultrasonically cleaned in acetone, ethanol, and deionized water for 20 minutes each. Then it is immersed in freshly prepared piranha solution (V concentrated sulfuric acid:V 30% hydrogen peroxide = 7:3) and treated at 100℃ for 1 hour. After removal, it is washed with a large amount of deionized water and the surface is dried with nitrogen.

[0081] S2. Silanization modification: The cleaned ceramic sheet was immersed in an anhydrous ethanol solution containing 2% (v / v) 3-aminopropyltriethoxysilane and reacted in a 60°C water bath for 3 hours. After removal, it was rinsed several times with ethanol and cured in a 120°C oven for 1 hour to obtain a ceramic substrate with an amino-rich surface.

[0082] S3, Primary Silver Loading: The modified ceramic sheet is immersed in a 0.05 mol / L silver nitrate solution and left to stand at 60°C in the dark for 12 hours to allow silver ions to fully coordinate with the amino groups on the surface.

[0083] S4, Secondary Silver Loading: Remove the ceramic sheet, rinse it gently with deionized water, and quickly transfer it to 1000 mL of nano-silver in-situ generation solution containing 0.1 g PVP, 63.5 g AgNO3 and 0.02 g sodium citrate. Purge the solution with nitrogen for 30 minutes to remove dissolved oxygen, and then heat it to 90 °C under continuous nitrogen protection and magnetically stir the reaction for 6 hours.

[0084] S5. Post-treatment: After the reaction, thoroughly wash the sample with deionized water until the washing solution is colorless and clear. Place the sample in a vacuum drying oven at 60℃ to dry. Finally, heat-treat the dried sample at 300℃ for 2 hours under argon protection. After natural cooling, the final silver-loaded antibacterial ceramic sheet product is obtained.

[0085] Example 6

[0086] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0087] Steps S1, S2, and S3 are exactly the same as in Example 1.

[0088] S4, Secondary Silver Loading: After gently rinsing the ceramic sheet with deionized water, transfer it to 200 mL of nano-silver in-situ generation solution containing 6.35 g PVP, 0.1 g AgNO3 and 0.1 g sodium citrate. Purge the solution with nitrogen for 30 minutes to remove dissolved oxygen. Then, under continuous nitrogen protection, heat to 95 °C and react with magnetic stirring for 4 hours.

[0089] S5. Post-processing: The steps are exactly the same as in Example 1.

[0090] Example 7

[0091] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0092] Steps S1, S2, and S3 are exactly the same as in Example 1.

[0093] S4, Secondary Silver Loading: After gently rinsing the ceramic sheet with deionized water, place it in 200mL of nano-silver in-situ generation solution containing 6.35g PVP, 0.1g AgNO3 and 0.1g sodium citrate. Purge the solution with nitrogen for 30 minutes to remove dissolved oxygen. Then, under continuous nitrogen protection, raise the temperature to 80℃ and stir magnetically for 4 hours.

[0094] S5. Post-processing: The steps are exactly the same as in Example 1.

[0095] Example 8

[0096] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0097] Steps S1, S2, and S3 are exactly the same as in Example 1.

[0098] S4, Secondary silver loading: After primary silver loading and rinsing, the ceramic sheet was placed in 200 mL of nano-silver in-situ generation solution containing 5.0 g PVP, 0.5 g AgNO3 and 0.1 g sodium citrate. Nitrogen gas was introduced into the solution for 30 minutes to remove dissolved oxygen. Then, under continuous nitrogen protection, the temperature was raised to 80 °C and the reaction was magnetically stirred for 4 hours.

[0099] S5. Post-processing: The steps are exactly the same as in Example 1.

[0100] Example 9

[0101] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0102] S1. Pretreatment: The alumina ceramic sheet was ultrasonically cleaned for 20 minutes each in acetone, ethanol, and deionized water. Then it was immersed in a freshly prepared piranha solution and treated at 55°C for 2 hours. After removal, it was washed with plenty of deionized water and dried with nitrogen.

[0103] The subsequent steps S2-S5 are exactly the same as in Example 1.

[0104] Example 10

[0105] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0106] S1. Pretreatment: The alumina ceramic sheet was ultrasonically cleaned for 20 minutes each in acetone, ethanol, and deionized water. Then it was immersed in a freshly prepared piranha solution and treated at 130°C for 2.5 hours. After removal, it was washed with plenty of deionized water and dried with nitrogen.

[0107] The subsequent steps S2-S5 are exactly the same as in Example 1.

[0108] Example 11

[0109] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0110] Steps S1 and S2 are exactly the same as in Example 1.

[0111] S3, Primary Silver Loading: The modified ceramic sheet is immersed in 200 ml of 0.2 mol / L silver nitrate solution and stirred at 50℃ for 3 hours to allow silver ions to fully coordinate with the amino groups on the surface.

[0112] The subsequent steps S4-S5 are exactly the same as in Example 1.

[0113] Example 12

[0114] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0115] Steps S1 and S2 are exactly the same as in Example 1.

[0116] S3, Primary Silver Loading: The modified ceramic sheet is immersed in 200 ml of 0.2 mol / L silver nitrate solution and stirred at 90℃ for 13 hours to allow silver ions to fully coordinate with the amino groups on the surface.

[0117] The subsequent steps S4-S5 are exactly the same as in Example 1.

[0118] Example 13

[0119] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0120] Steps S1, S2, and S3 are exactly the same as in Example 1.

[0121] S4, Secondary Silver Loading: Remove the ceramic sheet, rinse it gently with deionized water, and quickly transfer it to 200 mL of nano-silver in-situ generation solution containing 6.35 g PVP, 0.1 g AgNO3 and 0.1 g sodium citrate. Purge the solution with nitrogen for 30 minutes to remove dissolved oxygen. Then, under continuous nitrogen protection, heat to 60 °C and magnetically stir the reaction for 1.5 hours.

[0122] S5. Post-processing: The steps are exactly the same as in Example 1.

[0123] Example 14

[0124] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0125] Steps S1, S2, and S3 are exactly the same as in Example 1.

[0126] S4, Secondary Silver Loading: Remove the ceramic sheet, rinse it gently with deionized water, and quickly transfer it to 200 mL of nano-silver in-situ generation solution containing 6.35 g PVP, 0.1 g AgNO3 and 0.1 g sodium citrate. Purge the solution with nitrogen for 30 minutes to remove dissolved oxygen. Then, under continuous nitrogen protection, heat to 100 °C and react with magnetic stirring for 7 hours.

[0127] S5. Post-processing: The steps are exactly the same as in Example 1.

[0128] Example 15

[0129] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0130] Steps S1, S2, S3, and S4 are exactly the same as in Example 1.

[0131] S5. Post-treatment: After the reaction, thoroughly wash the sample with deionized water until the washing solution is colorless and clear. Place the sample in a vacuum drying oven at 60℃ to dry. Finally, heat-treat the dried sample at 100℃ for 0.5 hours under argon protection. After natural cooling, the final silver-loaded antibacterial ceramic sheet product is obtained.

[0132] Example 16

[0133] A method for preparing a long-lasting antibacterial ceramic silver-loaded material includes the following steps:

[0134] Steps S1, S2, S3, and S4 are exactly the same as in Example 1.

[0135] S5. Post-treatment: After the reaction, thoroughly wash the sample with deionized water until the washing solution is colorless and clear. Place the sample in a vacuum drying oven at 60℃ to dry. Finally, heat-treat the dried sample at 350℃ for 3 hours under argon protection. After natural cooling, the final silver-loaded antibacterial ceramic sheet product is obtained.

[0136] Comparative Example 1

[0137] This comparative example uses most of the steps in Example 1 to prepare the ceramic silver-loaded material, except that the secondary silver loading step S4 is omitted.

[0138] Comparative Example 2

[0139] This comparative example uses most of the steps in Example 1 to prepare the ceramic silver-loaded material, except that the silanization modification step S2 is omitted.

[0140] Comparative Example 3

[0141] This comparative example uses most of the operational steps of Example 1 to prepare the ceramic silver-supported material, with the difference being that in step S2, the organic-inorganic hybrid molecular layer is constructed through modification with methyltriethoxysilane. The specific operation of step S2 is as follows:

[0142] The cleaned ceramic sheet was immersed in an anhydrous ethanol solution containing 2% (v / v) methyltriethoxysilane (without -NH2 or -SH) and reacted in a water bath at 60°C for 3 hours. After removal, it was rinsed several times with ethanol and cured in an oven at 120°C for 1 hour to obtain a ceramic substrate with an amino-rich surface.

[0143] Comparative Example 4

[0144] This comparative example uses most of the steps in Example 1 to prepare the ceramic silver-loaded material, except that no roughening and activation treatment is performed in step S1.

[0145] The specific operation of step S1 is as follows: The alumina ceramic sheet is ultrasonically cleaned in acetone, ethanol, and deionized water for 20 minutes each. Then it is rinsed with plenty of deionized water and the surface is dried with nitrogen gas.

[0146] Comparative Example 5

[0147] This comparative example uses most of the operating steps in Example 1 to prepare the ceramic silver-loaded material, except that: there is no silanization modification step S2 and primary silver loading step S3, only physical adsorption reduction.

[0148] Comparative Example 6

[0149] This comparative example uses most of the operating steps in Example 1 to prepare the ceramic silver-loaded material. The difference is that: in-situ reduction is performed first, followed by ion exchange, that is, secondary silver loading step S4 is performed first, followed by primary silver loading step S3.

[0150] The silver-loaded materials prepared by the methods described in Examples 1-16 and Comparative Examples 1-6 were subjected to performance tests. The test data are shown in Table 1.

[0151]

[0152]

[0153] Examples 1-5 of this invention all employ a complete process flow of ceramic substrate pretreatment, silanization modification, stepwise composite silver loading (primary silver loading + secondary silver loading), and post-treatment, with optimized parameters controlled in key steps. All examples exhibit high and stable silver loading (13.8-15.1 wt%), excellent initial antibacterial rate (100% antibacterial rate after 24 hours), significant long-term antibacterial performance (≥99.2% after 10 days, ≥98.3% after 30 days), high silver binding strength, and controllable release behavior. This indicates that the preparation method described in this invention has good applicability and repeatability on different ceramic materials (such as alumina, silicon nitride, zirconium oxide, etc.). Examples 6-16 involve changing the roughening temperature, ion exchange time, reduction temperature, heat treatment temperature, and Ag... + The system shows that when a single parameter such as the ratio of silver to PVP deviates from the preferred range described in this invention, it will lead to a deterioration in silver loading, silver particle dispersibility, binding strength or release kinetics, thereby causing a significant decrease in antibacterial performance, especially long-lasting performance.

[0154] Comparative Example 1 (only primary ion exchange loading, lacking secondary in-situ reduction) showed a significant decrease in silver loading and a sharp decline in long-term antibacterial performance, demonstrating that the in-situ construction of silver nanoparticles is crucial for long-term release. Comparative Examples 2 and 5 (lacking silanization modification) showed weak silver binding and easy detachment, resulting in a significant decrease in long-term performance, highlighting that chemical anchoring of the molecular layer is the foundation for achieving high binding strength. Comparative Example 3 (using a silane coupling agent without -NH2 or -SH) lacked coordinating groups, resulting in weak silver binding and significantly inferior performance compared to the examples, demonstrating that active groups are key to strong chemical bonding. Comparative Example 4 (lacking roughening and activation treatment) had insufficient surface hydroxyl groups, leading to weak molecular layer binding and poor subsequent silver loading, indicating that surface pretreatment is a prerequisite for the success of subsequent steps. Comparative Example 6 (reversed loading order, reduction followed by ion exchange) showed uneven silver distribution, uncontrolled release behavior, and a significant decrease in antibacterial performance, especially long-term performance, confirming the rationality of the order of first ion exchange fixation and then in-situ reduction growth.

[0155] This invention solves the technical problems of low silver bonding strength, easy detachment, and uncontrollable release behavior in ceramic silver-loaded materials by synergistic effect of surface chemical anchoring molecular layer construction and stepwise composite silver loading process. The prepared material has high silver loading, rapid antibacterial effect and excellent long-lasting antibacterial performance.

[0156] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the nature and scope of the present invention. Various modifications made to the above embodiments by those skilled in the art after reading this specification are all within the scope of protection of the present invention.

Claims

1. A method for preparing a long-lasting antibacterial ceramic silver-loaded material, characterized in that, Includes the following steps: S1. Ceramic substrate pretreatment: The ceramic substrate is cleaned and roughened to obtain a clean, rough surface rich in hydroxyl groups. S2, Silanization modification: On the surface of the pretreated ceramic substrate, an organic-inorganic hybrid molecular layer containing amino or thiol groups is constructed; S3, Primary silver loading: Immerse the ceramic substrate treated in step S2 into an Ag-containing... + Ion exchange treatment was performed on the solution to allow Ag to... + It coordinates and chelates with the amino or thiol groups in the organic-inorganic hybrid molecular layer; S4, Secondary Silver Loading: The ceramic substrate after step S3 is placed in a mixed aqueous solution containing a silver source, stabilizer, and weak reducing agent, and an in-situ reduction reaction is carried out under inert gas protection, causing some Ag to be reduced. + The ceramic substrate surface and pores are reduced to nano-silver particles and deposited. S5. Post-processing: The loaded ceramic substrate is cleaned, dried and heat-treated to obtain the ceramic silver-loaded material.

2. The preparation method according to claim 1, characterized in that, In step S1, the roughening and activation treatment is performed by treating with a piranha solution at 60~100℃ for 0.5~2 hours.

3. The preparation method according to claim 2, characterized in that, In step S2, the organic-inorganic hybrid molecular layer is constructed by modification with a silane coupling agent; the silane coupling agent is 3-aminopropyltriethoxysilane or 3-mercaptopropyltrimethoxysilane.

4. The preparation method according to claim 1, characterized in that, In step S3, the Ag-containing + The solution is silver nitrate solution or silver ammonia solution; the ion exchange treatment is performed at a temperature of 60~80℃ for 4~12 hours.

5. The preparation method according to claim 1, characterized in that, In step S4, the silver source is silver nitrate, the stabilizer is polyvinylpyrrolidone, and the weak reducing agent is sodium citrate; the Ag in the mixed aqueous solution... + The mass ratio of polyvinylpyrrolidone to polyvinylpyrrolidone is (0.001~0.01):

1.

6. The preparation method according to claim 1, characterized in that, In step S4, the in-situ reduction reaction is carried out at a temperature of 70-90°C for 2-6 hours under nitrogen or argon protection.

7. The preparation method according to claim 1, characterized in that, In step S4, the heat treatment is carried out under an inert atmosphere or vacuum, at a temperature of 200~300℃, for a time of 0.5~2 hours.

8. A long-lasting antibacterial ceramic silver-loaded material prepared by the preparation method according to any one of claims 1-7.

9. The ceramic silver-supported material according to claim 8, characterized in that, Ag chelated through coordination exists simultaneously on the surface and near the surface of the material. + And through in-situ reduction deposition of silver nanoparticles, a rapid release zone and a slow release zone of silver ions are formed.

10. An antibacterial product, characterized in that, It includes the ceramic silver-loaded material as described in claim 8 or 9.

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