A copper-doped titanium-based energy storage antibacterial material, its preparation method and application

Abstract

This invention discloses a copper-doped titanium-based energy storage antibacterial material, its preparation method, and its application, belonging to the field of biofouling control technology. The preparation method is as follows: After pretreatment of the titanium-based material, it undergoes two anodic oxidation processes, followed by electrodeposition in a copper ion solution. After cleaning and drying, it is annealed, and then charged using a three-electrode system to obtain the copper-doped titanium-based energy storage antibacterial material. This material has a simple preparation method, combines charge storage and chemical sterilization functions, exhibits good antibacterial durability, and demonstrates excellent antibacterial effects against electroactive bacteria such as *Pseudomonas aeruginosa*, which are dominant corrosive and fouling bacteria in marine environments. It also significantly reduces the risk of bacterial drug resistance and is recyclable.

Description

Technical Field

[0001] This invention relates to the field of biofouling control technology, and in particular to a copper-doped titanium-based energy storage antibacterial material, its preparation method, and its application. Background Technology

[0002] The information disclosed in the background section of this invention is intended only to enhance the understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] Titanium and its alloys are widely used in marine engineering manufacturing due to their excellent mechanical properties and corrosion resistance; however, their surfaces are susceptible to biofouling. Biofouling not only increases ship drag and fuel consumption but can also cause pipe blockages and perforations, seriously threatening equipment safety. Controlling the initial adhesion and aggregation of microorganisms is crucial for preventing biofouling.

[0004] In existing antibacterial technologies, relying solely on chemical coatings for antibacterial action can easily induce bacterial resistance; photocatalytic TiO2-based antibacterial materials, such as Cu... + TiO2 nanotube array heterostructures achieve sterilization by generating electron-hole pairs through ultraviolet light irradiation to excite reactive oxygen species (ROS). However, the wide bandgap of TiO2 limits its applicability to UV irradiation environments, and issues with electron transfer and electron-hole recombination rates further reduce sterilization efficiency. Another type of electrochemically active titanium-based antibacterial material, such as carbon / TiO2 nanotube array antibacterial platforms, relies on double-layer capacitance to store charges and disrupt bacterial membranes. There are also two-dimensional porous titanium-based antibacterial materials, such as titanium micro-arc oxidation copper-loaded coatings, which achieve antibacterial effects by chemically plating copper to alter the bacterial adhesion microenvironment. However, these technologies generally suffer from limited sterilization response range and insufficient capacitance, resulting in poor antibacterial durability, and most antibacterial materials are difficult to recycle.

[0005] In addition, some electroactive bacteria in the ocean (such as Pseudomonas and sulfate-reducing bacteria) directly or indirectly accelerate the electrochemical corrosion of metals through extracellular electron transfer (EET) and biofilm formation. However, existing antibacterial materials are not effective against these electroactive bacteria, which limits the application effect of existing materials in the prevention and control of biofouling in marine engineering equipment.

[0006] Therefore, how to provide a titanium-based antibacterial material that combines electrostatic antibacterial and chemical bactericidal effects, has strong antibacterial durability, good bactericidal effect on electroactive bacteria, is simple to prepare, and can be recycled is an urgent problem to be solved. Summary of the Invention

[0007] In view of this, the present invention provides a copper-doped titanium-based energy storage antibacterial material, its preparation method and application. The energy storage antibacterial material provided by the present invention has both charge antibacterial and chemical bactericidal effects, and has a good antibacterial effect on electroactive bacteria. It has strong antibacterial durability, and the preparation method is simple and can be recycled.

[0008] In a first aspect, the present invention provides a method for preparing a copper-doped titanium-based energy storage and antibacterial material, comprising the following steps:

[0009] After pretreatment, the titanium-based material was subjected to two anodic oxidation processes to obtain a titanium-based material containing a TiO2 nanotube array.

[0010] Titanium-based materials containing TiO2 nanotube arrays were electrodeposited in a copper ion solution, and after cleaning and drying, they were annealed to obtain copper-doped titanium-based materials.

[0011] A copper-doped titanium-based material was charged using a three-electrode system to obtain a copper-doped titanium-based energy storage and antibacterial material.

[0012] Preferably, the titanium-based material is selected from pure titanium or titanium alloy, and the titanium-based material further includes a pretreatment step before anodizing, the pretreatment being pickling, acetone washing, ethanol washing and water washing in sequence.

[0013] Preferably, the anodizing process employs a two-electrode system, with a titanium-based material as the anode and a graphite electrode or platinum sheet as the cathode. The voltage for the anodizing treatment is 40~80V, and the time is 0.5~2h. The electrolyte for the anodizing treatment is an aqueous solution of ethylene glycol containing ammonium fluoride.

[0014] Preferably, after the first anodizing treatment, the generated TiO2 nanotube array is removed by acid washing, and then a second anodizing treatment is performed.

[0015] Preferably, the concentration of copper ions in the copper ion solution is 0.3~1 mol / L; the anions in the copper ion solution are selected from one or more of nitrate ions, chloride ions, sulfate ions, pyrophosphate ions, or cyanide ions.

[0016] Preferably, the electrodeposition process uses a titanium-based material containing a TiO2 nanotube array as the cathode and a platinum sheet or graphite electrode as the anode; the electrodeposition voltage is 10~20V and the time is 50~150s.

[0017] Preferably, the annealing temperature is 400~500℃ and the annealing time is 2~5h.

[0018] Preferably, the three-electrode system includes a working electrode, a counter electrode, and a reference electrode, wherein the working electrode is a copper-doped titanium-based material; the charging voltage is 0.8~1.2V, and the charging time is 10~30min.

[0019] Secondly, the present invention provides a copper-doped titanium-based energy storage and antibacterial material prepared by the above preparation method.

[0020] Thirdly, the present invention provides the application of the above-mentioned copper-doped titanium-based energy storage antibacterial material in the prevention and control of biofouling.

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

[0022] (1) This invention constructs a titanium-based material containing highly ordered TiO2 nanotube arrays (TNTs) through two anodic oxidation processes. The copper ion electrodeposition and annealing processes are combined to achieve uniform doping of copper elements and stability of TNTs. After charging treatment, a composite antibacterial material with both charge storage and chemical sterilization functions is formed. The antibacterial durability is good, which solves the technical defects of traditional TiO2-based materials that rely on ultraviolet light, have insufficient capacitance of electrochemical active materials, and have poor antibacterial durability.

[0023] (2) The present invention can store charge by charging at a low voltage of 0.8~1.2V for 10~30 minutes. During the subsequent discharge process, it can interfere with the extracellular electron transfer of electroactive bacteria. At the same time, it can form a synergistic antibacterial mechanism by utilizing the chemical bactericidal effect of copper ions. It has good broad-spectrum antibacterial properties. It also has a good inhibitory effect on electroactive bacteria such as Pseudomonas aeruginosa, which dominate corrosion and fouling in the marine environment. Moreover, it can significantly reduce the risk of bacterial drug resistance. After the discharge is completed, it can be recycled by recharging.

[0024] (3) The preparation method of the present invention is simple to operate, the titanium-based material pretreatment and anodizing process are compatible with industrial pure titanium and titanium alloy substrates, the copper doping concentration and charge and discharge parameters are controllable, and the obtained material can be stably used in complex environments such as ocean and soil, providing a practical and long-term solution for the prevention and control of biofouling of marine engineering equipment. Attached Figure Description

[0025] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation thereof. Obviously, those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0026] Figure 1These are scanning electron microscope (SEM) images of the copper-doped titanium-based energy storage and antibacterial materials of Examples 1-4 of the present invention at magnifications of 300 and 50K, wherein (a) is TNTs-0.35Cu of Example 3, (b) is TNTs-0.55Cu of Example 2, (c) is TNTs-0.75Cu of Example 1, and (d) is TNTs-0.55Cu-2 of Example 4;

[0027] Figure 2 These are three-dimensional morphology images of the surface of the TNTs-0.75Cu sample in Embodiment 1 of the present invention, wherein (a) is a top view and (b) is a side view;

[0028] Figure 3 This is a graph showing the surface elemental analysis results of the TNTs-0.75Cu sample from Example 1 of this invention;

[0029] Figure 4 The above are X-ray photoelectron spectroscopy (XPS) spectra of the TNTs-0.75Cu sample surface in Example 1 of this invention, wherein (a) is the XPS spectrum of the C 1s level, (b) is the XPS spectrum of the O 1s level, (c) is the XPS spectrum of the Ti 2p level, and (d) is the XPS spectrum of the Cu 2p level.

[0030] Figure 5 This section characterizes the capacitance of TNTs-0.75Cu in Example 1 and Ti foil in Comparative Example 1. (a) shows the cyclic voltammetry (CV) curves of TNTs-0.75Cu at different scan rates; (b) shows the CV curves of TNTs-0.75Cu and Ti foil at a scan rate of 1 V / s; (c) shows the galvanostatic charge-discharge (GCD) curves of TNTs-0.75Cu at different scan current densities; and (d) shows the capacitance of TNTs-0.75Cu and Ti foil at a scan current density of 1 mA·cm⁻¹. -2 The GCD curve below;

[0031] Figure 6 This document presents corrosion resistance tests on UC-TNTs-0.75Cu and CD-TNTs-0.75Cu samples from Example 1 of the present invention, as well as UC-Ti from Comparative Example 1 and CD-Ti from Comparative Example 2. (a) shows the Nyquist curves of the UC-TNTs-0.75Cu and CD-TNTs-0.75Cu samples; (b) shows the Bode modulus plots of the UC-TNTs-0.75Cu and CD-TNTs-0.75Cu samples; (c) shows the Nyquist curves of UC-Ti and CD-Ti; and (d) shows the Bode modulus plots of UC-Ti and CD-Ti.

[0032] Figure 7These are images of the antibacterial performance tests of UC-TNTs-0.75Cu and CD-TNTs-0.75Cu samples from Example 1 of the present invention, as well as UC-Ti from Comparative Example 1 and CD-Ti from Comparative Example 2. Among them, (a) is a fluorescence microscope image, (b) is the anti-adhesion rate, and (c) is the sterilization rate.

[0033] Figure 8 The samples of Embodiment 1, Comparative Example 1, and Comparative Example 2 of this invention are in P. aeruginosa SEM images of bacteria immobilized on the surface after soaking in bacterial solution for 12 hours, magnified at 5K and 50K; where (a) is the UC-Ti sample of Comparative Example 1, (b) is the CD-Ti sample of Comparative Example 2, (c) is the UC-TNTs-0.75Cu sample of Example 1, and (d) is the CD-TNTs-0.75Cu sample of Example 1;

[0034] Figure 9 The samples of Embodiment 1, Comparative Example 1, and Comparative Example 2 of this invention are in P. aeruginosa Images of bacterial colonies attached to the surface after immersion in bacterial solution for 12 hours; where (a1), (a2), and (a3) ​​are images of UC-Ti samples from Comparative Example 1 after immersion in bacterial solution diluted 10 times. 4 times, 10 5 times, 10 6 Images of colonies after dilution; (b1), (b2), and (b3) are images of the CD-Ti sample from Comparative Example 2 after dilution of 10 times. 4 times, 10 5 times, 10 6 Images of colonies after dilution; (c1), (c2), and (c3) are images of the UC-TNTs-0.75Cu sample from Example 1 after dilution of 10 times. 4 times, 10 5 times, 10 6 Images of colonies after dilution; (d1), (d2), and (d3) are images of the CD-TNTs-0.75Cu sample from Example 1 after dilution of 10 times in bacterial culture. 4 times, 10 5 times, 10 6 Images of bacterial colonies after magnification. Detailed Implementation

[0035] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0036] This invention provides a method for preparing a copper-doped titanium-based energy storage and antibacterial material, comprising the following steps:

[0037] After pretreatment, the titanium-based material was subjected to two anodic oxidation processes to obtain a titanium-based material containing a TiO2 nanotube array.

[0038] Titanium-based materials containing TiO2 nanotube arrays were electrodeposited in a copper ion solution, and after cleaning and drying, they were annealed to obtain copper-doped titanium-based materials.

[0039] A copper-doped titanium-based material was charged using a three-electrode system to obtain a copper-doped titanium-based energy storage and antibacterial material.

[0040] This invention utilizes a two-stage anodizing process on the surface of a titanium-based material to construct a highly ordered titanium dioxide nanotube array structure on a metal substrate through electrochemical oxidation. This nanotube array not only provides a high specific surface area carrier framework for subsequent copper doping, but its tubular structure itself can also achieve charge storage through the electric double layer effect. Subsequently, the nanotube array is placed in a copper ion solution for electrodeposition. An external electric field drives the copper ions to migrate directionally and embed into the tube walls and internal voids of the nanotubes. After annealing, the copper element exists stably in the titanium dioxide lattice in the form of oxides or doped atoms, forming a composite structure with redox activity. Finally, a three-electrode system is used for charging to achieve rapid charge storage and slow release. The stored charge can interfere with the extracellular electron transfer of microorganisms through electrostatic interaction during application, while the slow release of copper ions exerts a chemical bactericidal effect. The two work synergistically to construct an energy storage antibacterial system with both physical and chemical mechanisms.

[0041] In this invention, the titanium-based material is selected from pure titanium or titanium alloys, specifically any one of Ti-6Al-4V alloy, TC4 titanium alloy, TA2 industrial pure titanium, or TA3 industrial pure titanium, which can be selected according to actual application requirements. The titanium-based material also includes a pretreatment step before anodizing, which consists of acid washing, acetone washing, ethanol washing, and water washing. These multi-step cleaning steps effectively remove oxide scale, oil, and impurities from the surface of the titanium-based material, improving surface cleanliness and activity, and laying a good foundation for the subsequent anodizing preparation of high-quality TiO2 nanotube arrays.

[0042] In this invention, the anodizing process employs a two-electrode system, using a titanium-based material as the anode and a graphite electrode or platinum sheet as the cathode. The anodizing voltage is 40-80V, more preferably 50-70V, and even more preferably 55-65V; the time is 0.5-2 hours. The electrolyte for the anodizing process is an aqueous solution of ethylene glycol containing ammonium fluoride. This invention does not impose any special restrictions on the specific amount of electrolyte used; a commonly used ratio in the art is acceptable. In one or more embodiments of this invention, the concentration of ammonium fluoride is 0.08-0.12 mol / L, and the volume ratio of ethylene glycol to water is (8-12):1.

[0043] This invention involves removing the generated TiO2 nanotube array through acid washing after the first anodizing treatment, followed by a second anodizing treatment. The TiO2 nanotube array generated in the first anodizing treatment has an uneven structure and poor order. After being removed by acid washing, the second anodizing can be performed on a cleaner and more uniform titanium-based material surface, thereby preparing a TiO2 nanotube array with a more regular structure and higher order, which is beneficial to improving the material's performance.

[0044] In the copper ion solution described in this invention, the concentration of copper ions is 0.3~1 mol / L, more preferably 0.5~0.8 mol / L, and even more preferably 0.6~0.8 mol / L; the concentration of copper ions affects the amount of Cu doping. The anions in the copper ion solution are selected from one or more of nitrate ions, chloride ions, sulfate ions, pyrophosphate ions, or cyanide ions.

[0045] In this invention, the electrodeposition process uses a titanium-based material containing a TiO2 nanotube array as the cathode and a platinum sheet or graphite electrode as the anode; the electrodeposition voltage is 10~20V, more preferably 12~18V; the electrodeposition time is 50~150s, more preferably 50~80s. If the electrodeposition time is too long, it will affect the structural integrity of the TiO2 nanotube array, which is not conducive to improving the performance of the material.

[0046] In this invention, the annealing temperature is 400~500℃, more preferably 420~480℃; the annealing time is 2~5h. Annealing can make the crystal structure of copper-doped titanium-based materials more stable, improve the conductivity and chemical stability of the materials, and at the same time promote the diffusion and uniform distribution of copper elements in the TiO2 lattice, thereby enhancing the energy storage and antibacterial properties of the materials.

[0047] In this invention, the three-electrode system includes a working electrode, a counter electrode, and a reference electrode. The working electrode is a copper-doped titanium-based material. The counter electrode can be a platinum electrode or a graphite electrode, and the reference electrode can be a saturated calomel electrode, a silver / silver chloride electrode, a mercury / mercury oxide electrode, etc., and this invention does not impose any special limitations on these. This invention does not impose any special limitations on the electrolyte of the three-electrode system; a liquid culture medium can be used as the electrolyte.

[0048] In this invention, the charging voltage is 0.8~1.2V, and the charging time is 10~30min, more preferably 15~20min. The charging process activates the energy storage performance of the material, enabling it to rapidly store and slowly release charge during application, thereby exerting its energy storage and antibacterial effect. This invention does not impose special limitations on the apparatus for the three-electrode system charging process; however, an electrochemical workstation is preferably used for the charging process.

[0049] The present invention also provides a copper-doped titanium-based energy storage and antibacterial material prepared by the above preparation method.

[0050] This invention also provides the application of the above-mentioned copper-doped titanium-based energy storage antibacterial material in the prevention and control of biofouling, especially suitable for the prevention and control of biofouling by electrically active bacteria.

[0051] The copper-doped titanium-based energy storage antibacterial material of this invention, during application, can release charge through its own energy storage properties, interfering with the extracellular electron transfer of electroactive bacteria. Simultaneously, copper exerts an antibacterial effect, thereby effectively inhibiting the growth of electroactive bacteria and the attachment of biofilms. The electroactive bacteria can be of the genus *Geobacterium* (…). Geobacter Shewanella ( ) Shewanella ), Pseudomonas aeruginosa ( P. aeruginosa ), Leuconostoc mesentery L. mesenteroides ), Lactococcus lactis ( L. lactis Iron-reducing red bacterium and sulfur-reducing soil bacterium, etc., in one or more embodiments of the present invention, the electroactive bacteria are Pseudomonas aeruginosa ( P. aeruginosa ).

[0052] The technical solution of the present invention will be further described below with reference to specific embodiments. The present invention does not impose any special restrictions on the source of reagents used in the following embodiments; commercially available products well known to those skilled in the art can be used.

[0053] In the following examples, the LB liquid culture medium consisted of 10 g tryptone, 5 g yeast extract, 10 g sodium chloride and 1 L deionized water.

[0054] Example 1

[0055] This embodiment provides a copper-doped titanium-based energy storage antibacterial material and its preparation method.

[0056] (1) Pretreatment: Titanium foil (TA2 industrial pure titanium) with dimensions of 10 mm × 10 mm × 0.1 mm was immersed in 1 mol / L hydrochloric acid solution for 3 h. After being immersed in hydrochloric acid, the titanium foil was ultrasonically cleaned in acetone, anhydrous ethanol and deionized water for 15 min in sequence, and then dried for later use.

[0057] (2) Anodizing: The titanium foil (Ti foil) cleaned and dried in step (1) was used as the anode, and the graphite electrode was used as the cathode. The electrolyte solution was an organic solvent system (1.15 g NH4F dissolved in 300 mL ethylene glycol and 33 mL deionized water). The distance between the two electrodes was kept at about 1 cm. A constant voltage of 60 V was applied between the anode and cathode using a DC power supply system. The first anodizing treatment was carried out under magnetic stirring for 1 h. The Ti foil after the first anodizing was taken out and ultrasonically cleaned with 0.7 mol / L hydrochloric acid solution for 1 h to remove the first oxide layer, resulting in a bright Ti foil. The foil was then cleaned and dried for later use. The Ti foil with the first oxide layer removed was subjected to a second anodizing under the same conditions for 1 h to obtain a Ti foil containing highly ordered TNTs.

[0058] (3) Copper deposition and annealing: A dual-electrode system was used, with the Ti foil containing highly ordered TNTs obtained in step (2) as the cathode and a platinum electrode as the anode. The electrode was placed in a 0.75 mol / L Cu(NO3)2·3H2O solution, and a DC voltage of 15 V was maintained. The deposition time was 60 s to allow copper ions to be rapidly deposited onto the TNTs surface. Then, the TNTs were rinsed three times with anhydrous ethanol and deionized water, dried, and annealed in a muffle furnace at an annealing temperature of 450℃ for 3 h to obtain copper-doped titanium-based material, denoted as TNTs-0.75Cu or UC-TNTs-0.75Cu.

[0059] (4) Charging treatment: A three-electrode system was adopted, with TNTs-0.75Cu sample as working electrode, metal platinum electrode (1cm×1cm) as auxiliary electrode, and saturated calomel electrode (SCE) as reference electrode; LB liquid medium was used as electrolyte, and the sample was charged at 1V for 15 min; copper-doped titanium-based energy storage antibacterial material was obtained, denoted as CD-TNTs-0.75Cu.

[0060] Example 2

[0061] The difference between this embodiment and embodiment 1 is that the concentration of Cu(NO3)2·3H2O in this embodiment is 0.55 mol / L, and the copper-doped titanium-based material obtained in step (3) of this embodiment is denoted as TNTs-0.55Cu.

[0062] Example 3

[0063] The difference between this embodiment and embodiment 1 is that the concentration of Cu(NO3)2·3H2O in this embodiment is 0.35 mol / L, and the copper-doped titanium-based material obtained in step (3) of this embodiment is denoted as TNTs-0.35Cu.

[0064] Example 4

[0065] The difference between this embodiment and embodiment 2 is that the deposition time in step (3) of this embodiment is 120s, and the copper-doped titanium-based material obtained in step (3) of this embodiment is denoted as TNTs-0.55Cu-2.

[0066] Comparative Example 1

[0067] The difference between this comparative example and Example 1 is that this comparative example only performs step (1) to obtain a pretreated Ti foil, denoted as UC-Ti.

[0068] Comparative Example 2

[0069] Compared with Comparative Example 1, this comparative example uses a three-electrode system, with pretreated Ti foil as the working electrode, a platinum metal electrode (1 cm × 1 cm) as the auxiliary electrode, and a saturated calomel electrode (SCE) as the reference electrode; LB liquid medium is used as the electrolyte, and the sample is charged at 1 V for 15 min, denoted as CD-Ti.

[0070] 1. Morphological characteristics

[0071] The surface morphology of TNTs-0.75Cu from Example 1, TNTs-0.55Cu from Example 2, TNTs-0.35Cu from Example 3, and TNTs-0.55Cu-2 from Example 4 were characterized using field emission scanning electron microscopy (FESEM). The voltage was set to 5 kV, and the magnification was 5K and 50K. Figure 1 As shown, from (a) to (c), the copper ion concentration increased from 0.35 mol / L to 0.75 mol / L. It can be seen that the increase in copper ion concentration affects the morphology of TNTs. When the Cu(NO3)2·3H2O concentration is 0.75 mol / L, nanotube fragments are clearly visible on the TNT surface, but the tube openings are still clearly visible, and the TNTs still maintain a tubular structure. (Comparison) Figure 1 As shown in (b) and (d), when the Cu(NO3)2·3H2O concentration is 0.55 mol / L, increasing the electrodeposition time to 2 min results in severe TNT collapse, irregularity, and blockage of the TNT openings by the nanotube collapse material. Therefore, a Cu(NO3)2·3H2O concentration of 0.75 mol / L and an electrodeposition time of 1 min yield a TNTs-Cu nano-antibacterial platform with the highest Cu doping content and intact TNT structure.

[0072] High-precision three-dimensional morphology measurements were performed using a 3D ultra-depth-of-field microscope. The microstructure and size distribution of the Cu coating on the surface of the TNTs-0.75Cu sample in Example 1 were observed and analyzed from both vertical and horizontal perspectives. The magnification was 300. Figure 2 As shown, Figure 2 (a) is a top view and (b) is a side view; it can be seen that the copper deposits on the surface of the TNTs-0.75Cu sample have a large size distribution, the surface of the copper coating has large undulations, and the copper dendrite grains are large, which is consistent with the conclusions of FESEM above.

[0073] 2. Elemental Analysis

[0074] To further confirm that the deposits on the surface of the TNTs-0.75Cu sample in Example 1 are copper dendrites, energy-dispersive spectroscopy (EDS) analysis was performed on the spheroidal deposits on the surface of the TNTs-0.75Cu sample. The results are as follows: Figure 3 As shown, the dendrites on the surface of the TNTs-0.75Cu sample are mainly composed of three elements: C, O, and Cu.

[0075] The composition and valence state changes of Cu on the surface of TNTs-0.75Cu samples were tested using X-ray photoelectron spectroscopy (XPS). Figure 4 As shown in (a)~(d) in the figure, characteristic peaks of C 1s, O 1s, Ti 2p, and Cu 2p were clearly observed in the XPS test, indicating that the TNTs-0.75Cu sample contains four elements: carbon, oxygen, titanium, and copper. Figure 4 As shown in (b) of the O 1s spectrum, the strong peak at the binding energy of 529.98 eV is a characteristic peak of Ti-O, and this part of the O element comes from TNTs. Figure 4 (c) indicates that all Ti on the sample surface exists as TiO2. From Figure 4 In (d), it can be determined that Cu exists on the sample surface in the form of +2 oxidation state, indicating the presence of CuO on the sample surface.

[0076] 3. Capacitance Characterization

[0077] The capacitance of the TNTs-0.75Cu sample from Example 1 and the Ti foil from Comparative Example 1 was characterized using an electrochemical workstation. Cyclic voltammetry was performed on the TNTs-0.75Cu sample at scan rates of 0.1, 0.3, 1, 5, 0.01, and 10 V / s, and at scan rates of 1, 2, and 10 mA·cm⁻¹. -2 Constant current charge-discharge tests were performed at current density. The capacitive performance of Ti and TNTs-0.75Cu was compared using an electrochemical workstation.

[0078] Figure 5 Figures (a) and (c) show the cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) curves of the TNTs-0.75Cu sample at different scan rates and scan current densities. The TNTs-0.75Cu sample was subjected to a scan at a scan rate of 1 V·s. -1 The maximum area capacitance was observed at a scanning current density of 1 mA·cm⁻¹.-2 At that time, the longest charge-discharge time was observed, and the sample had the largest capacitance. Figure 5 As shown in (b) above, at 1 V·s -1 At the scan rate, the current of the TNTs-0.75Cu sample was significantly higher than that of the pure Ti foil sample, and the capacitance of the sample was nearly three times higher than that of the pure Ti foil. A similar capacitance trend was observed in the corresponding GCD curve. Figure 5 As shown in (d) in the figure, at 1 mA·cm -2 At the specified current density, the charge / discharge time of TNTs-0.75Cu is approximately 1700 s, which is significantly longer than that of pure Ti foil. This demonstrates that the capacitance of TNTs-0.75Cu is significantly improved compared to that of Ti foil.

[0079] 4. Corrosion resistance characterization

[0080] The corrosion resistance of UC-TNTs-0.75Cu and CD-TNTs-0.75Cu samples from Example 1, as well as UC-Ti from Comparative Example 1 and CD-Ti from Comparative Example 2, was further tested at open circuit potential using electrochemical impedance spectroscopy (EIS). The test frequency range was 10 mHz to 100 kHz, and the AC voltage amplitude was 50 mV.

[0081] In the Nyquist curve, for UC-Ti and CD-Ti, at Figure 6 In (c), a capacitor ring with a large radius was observed. The significant reduction in the radius of the capacitor ring in the charged Ti (CD-Ti) compared to the uncharged (UC-Ti) clearly indicates that the charging process causes a considerable degree of corrosion to the Ti foil. Figure 6 As shown in (a) of the diagram, the radius of the capacitor ring in the high-frequency region of the TNTs-0.75Cu sample does not change significantly, indicating that the charging process does not cause significant corrosion to the TNTs-0.75Cu sample. In the Bode modulus plot, in... Figure 6 In (d), the |Z| of the Ti foil (CD-Ti) after charging was observed. 0.01 The reduction in size compared to the uncharged Ti foil (UC-Ti) indicates that the charging process caused some degree of corrosion to the Ti foil. From... Figure 6 As can be seen in (b) of the image, the |Z| of the UC-TNTs-0.75Cu sample is... 0.01 The lack of significant changes indicates that it exhibits excellent stability in the electrolyte, which is consistent with the results of the Nyquist curve.

[0082] 5. Antibacterial properties

[0083] To observe the effects of UC-TNTs-0.75Cu and CD-TNTs-0.75Cu samples from Example 1, as well as UC-Ti samples from Comparative Example 1 and CD-Ti samples from Comparative Example 2 on Pseudomonas aeruginosa (… P. aeruginosa To investigate the inhibitory effect of [the substance], a bacterial live / dead staining kit was used to stain the bacteria after material treatment, and LB liquid medium was used as the culture medium. The inhibitory effect of [the substance] on [the material] was calculated using the following formula. P. aeruginosa Sterilization rate of bacteria ( D ) and anti-adhesion rate ( A ):

[0084] ;

[0085] ;

[0086] In the above formula, S 样死亡 S represents the area of ​​dead bacteria on the sample surface. 样总 S represents the total bacterial surface area of ​​the sample; 空白总 This represents the total area of ​​bacteria on the surface of the uncharged Ti foil.

[0087] Figure 7 (a) in the figure represents different samples in P. aeruginosa Fluorescence microscopy images of bacteria on the surface of the Ti foil after immersion in bacterial solution for 12 hours show that large areas of fluorescence were observed both before and after charging, indicating that a large number of bacteria adhered to the surfaces of both the uncharged Ti foil (UC-Ti) and the charged-discharged Ti foil (CD-Ti). However, compared to the uncharged Ti foil, the green fluorescence on the charged-discharged Ti foil surface was significantly dimmer, with large areas of red fluorescence interspersed. The charged-discharged Ti foil showed a higher proportion of dead bacteria and a lower number of live bacteria, with most in the early apoptosis stage, suggesting that the charge-discharge treatment has a certain bactericidal effect.

[0088] The fluorescence area of ​​uncharged TNTs-0.75Cu (UC-TNTs-0.75Cu) was significantly smaller than that of uncharged Ti foil (UC-Ti), indicating that the amount of bacteria attached to it was much smaller than that of Ti foil. This can be attributed to the release of Cu from CuO deposits on the surface of TNTs-0.75Cu. 2+ Upon entering the bacterial culture, a toxic liquid layer forms near the sample, inhibiting bacterial adhesion and growth to some extent. After charging and discharging, almost no fluorescence is observed on the surface of CD-TNTs-0.75Cu. Figure 7 As shown in (b) and (c), its anti-adhesion rate and sterilization rate are as high as 96.0±1.1% and 98.0±0.6%, respectively. Simultaneously, an antibacterial effect proportional to the capacitance after charging can be observed. Compared with Ti foil, TNTs-0.75Cu exhibits a significantly improved capacitance and demonstrates a superior antibacterial effect.

[0089] TNTs-0.75Cu was charged for 15 minutes and then discharged for 10 minutes as described in Example 1. After three cycles, the material maintained its high performance. Moreover, the time it spent on the bacterial surface increased after the cycle treatment, and the anti-adhesion rate and sterilization rate were improved to a certain extent. The anti-adhesion rate and sterilization rate were both measured to be above 99%.

[0090] Normal Pseudomonas aeruginosa cells have a regular cell morphology, are arranged in rod-shaped patterns, and have an intact structure. From Figure 8 As can be seen in (a), a large number of Pseudomonas aeruginosa bacteria adhered to the uncharged Ti foil, exhibiting typical biofilm characteristics of membrane-like wrapping, and polymeric secretions could be observed on the bacterial surface. Figure 8 As shown in (b), after charge-discharge treatment, the cell morphology changed significantly, with no obvious cell wall and the cells becoming shorter and rounder. Most cells atrophied and showed indentations, while some cells became shriveled or vacuolated, indicating that charging promoted apoptosis. Meanwhile, as... Figure 8 As shown in (c), the midsection of bacteria on the surface of uncharged TNTs-0.75Cu exhibits deformation and a shrinkage trend. This may be a result of the bacteria's stress response to Cu, including oxidative stress and DNA damage. Figure 8 In (d), the cell morphology was completely destroyed, most cells were lysed, and a large number of cell fragments appeared, indicating that the large amount of charge released after charging the TNTs-0.75Cu sample can effectively inhibit the attachment and growth of Pseudomonas aeruginosa cells, remove bacterial biofilms, destroy cell walls and cell membranes, and ultimately lead to bacterial death.

[0091] from Figure 9 Large colonies were observed on both uncharged Ti foil and Ti foil coated with bacterial solution after charge-discharge, significantly more than on TNTs-0.75Cu (CD-TNTs-0.75Cu) after charge-discharge and uncharged TNTs-0.75Cu (UC-TNTs-0.75Cu). The bacterial solution was diluted 10... 6 After the charge-discharge TNTs-0.75Cu (CD-TNTs-0.75Cu) sample was charged and discharged, no colony growth was observed on the agar plate, while single dispersed colonies were clearly observed in the remaining three groups.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a copper-doped titanium-based energy storage and antibacterial material, characterized in that, Includes the following steps: After pretreatment, the titanium-based material was subjected to two anodic oxidation processes to obtain a titanium-based material containing a TiO2 nanotube array. Titanium-based materials containing TiO2 nanotube arrays were electrodeposited in a copper ion solution, and after cleaning and drying, they were annealed to obtain copper-doped titanium-based materials. A copper-doped titanium-based material was charged using a three-electrode system to obtain a copper-doped titanium-based energy storage and antibacterial material.

2. The preparation method according to claim 1, characterized in that, The titanium-based material is selected from pure titanium or titanium alloy. Before the anodizing treatment, the titanium-based material also includes a pretreatment step, which consists of pickling, acetone washing, ethanol washing and water washing in sequence.

3. The preparation method according to claim 1, characterized in that, The anodizing process employs a two-electrode system, with titanium-based material as the anode and graphite electrode or platinum sheet as the cathode. The voltage for the anodizing treatment is 40~80V, and the time is 0.5~2h. The electrolyte for the anodizing treatment is an aqueous solution of ethylene glycol containing ammonium fluoride.

4. The preparation method according to claim 1, characterized in that, After the first anodizing treatment, the generated TiO2 nanotube array is removed by acid washing, and then a second anodizing treatment is performed.

5. The preparation method according to claim 1, characterized in that, The copper ion solution has a copper ion concentration of 0.3~1 mol / L; the anion in the copper ion solution is selected from one or more of nitrate ions, chloride ions, sulfate ions, pyrophosphate ions, or cyanide ions.

6. The preparation method according to claim 1, characterized in that, The electrodeposition process uses a titanium-based material containing TiO2 nanotube arrays as the cathode and a platinum sheet or graphite electrode as the anode; the electrodeposition voltage is 10~20V and the time is 50~150s.

7. The preparation method according to claim 1, characterized in that, The annealing temperature is 400~500℃, and the annealing time is 2~5h.

8. The preparation method according to claim 1, characterized in that, The three-electrode system includes a working electrode, a counter electrode, and a reference electrode. The working electrode is a copper-doped titanium-based material. The charging voltage is 0.8~1.2V, the charging time is 10~30min, and the discharging time is 5~15min.

9. The copper-doped titanium-based energy storage and antibacterial material prepared by the preparation method according to any one of claims 1 to 8.

10. The application of the copper-doped titanium-based energy storage antibacterial material as described in claim 9 in the prevention and control of biofouling.

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