A method for preparing a CuO-Pt nanocomposite

Abstract

This invention provides a method for preparing CuO-Pt nanocomposite materials, belonging to the technical field of sensor material preparation methods. The nanocomposite material obtained in this invention exhibits significant advantages in hydrogen peroxide colorimetric sensing, possessing excellent peroxidase-like activity, superior synergistic catalytic effect, and good sensing performance. CuO provides abundant active sites, while Pt nanoparticles possess highly efficient catalytic activity. This nanocomposite material can significantly accelerate the decomposition of hydrogen peroxide and the oxidation process of the chromogenic substrate, thereby greatly improving the sensitivity and detection efficiency of the colorimetric response. With its excellent sensing performance, the CuO-Pt nanocomposite material provides an ideal platform for constructing highly sensitive hydrogen peroxide colorimetric sensors, and has broad application prospects in biomedicine, environmental monitoring, and food safety.

Description

Technical Field

[0001] This invention relates to a method for preparing CuO-Pt nanocomposite materials, belonging to the technical field of sensor material preparation methods. Background Technology

[0002] Hydrogen peroxide (H2O2), as an important chemical substance, plays a crucial role in various fields such as environment, food, biology, and clinical diagnostics. In biological systems, H2O2 is a key messenger in cell signal transduction, but abnormally elevated concentrations are often closely related to pathological states such as oxidative stress, inflammation, diabetes, neurodegenerative diseases (such as Alzheimer's disease and Parkinson's disease), and cancer. At the environmental and industrial levels, H2O2 is widely used as a bleaching agent, disinfectant, and oxidant, and accurate monitoring of its residues is crucial for food safety and environmental protection. Therefore, developing analytical methods for rapid, sensitive, and selective detection of H2O2 has significant scientific and practical value for early disease diagnosis, food quality control, and environmental monitoring. Traditional H2O2 detection methods, such as chemical titration (potassium permanganate titration), chromatography (high performance liquid chromatography, ion chromatography), and spectrometry (Raman spectroscopy), while possessing high accuracy in specific scenarios, generally suffer from limitations such as expensive instruments, complex operation, cumbersome sample pretreatment, long processing times, and difficulty in achieving real-time on-site monitoring. For example, chemical titration relies on the operator's subjective judgment, which is prone to human error; while instrumental methods such as high-performance liquid chromatography and Raman spectroscopy require professional personnel and complex equipment, limiting their widespread application under resource-constrained conditions. To overcome these challenges, biosensors based on biological enzymes (such as horseradish peroxidase) have attracted much attention in recent years due to their high specificity and sensitivity. However, natural enzymes have revealed inherent defects in practical applications: their preparation and purification are costly, they are extremely sensitive to environmental conditions such as temperature and pH, they are prone to denaturation and inactivation, and they have poor storage stability. These bottlenecks greatly restrict their commercial application.

[0003] Against this backdrop, a class of nanomaterials with enzyme-like catalytic activity (nanozymes) has emerged, paving the way for the construction of novel sensing platforms. Compared with natural enzymes, nanozymes have significant advantages such as simple synthesis, low cost, high stability (heat resistance, acid and alkali resistance, and resistance to protease hydrolysis), tunable catalytic activity, and ease of surface functionalization. Since Academician Yan Xiyun's team first discovered that Fe3O4 nanoparticles possess peroxidase-like activity in 2007, a large amount of research has been dedicated to developing various nanomaterials with enzyme-like activities, including noble metals (Au, Ag, Pt), transition metal oxides (such as Co3O4, Fe3O4, CeO2), carbon-based nanomaterials, and metal-organic frameworks (MOFs). Among these, colorimetric sensing strategies have become one of the most promising directions for nanozyme applications due to their lack of complex instruments, ability to perform qualitative or semi-quantitative analysis by directly observing color changes with the naked eye, simple operation, and low cost. The principle is usually to utilize the peroxidase-like activity of nanozymes to catalyze the oxidation of a colorless substrate (3,3',5,5'-tetramethylbenzidine, TMB) in the presence of H2O2 to generate a colored product (blue oxTMB). The concentration of H2O2 can be quantitatively detected by measuring the absorbance.

[0004] Although single-component nanozymes (such as pure CuO nanoparticles or Pt nanoparticles) have exhibited certain enzyme-like activities, their catalytic efficiency is often insufficient to meet the needs of trace analysis. For example, the peroxidase-like activity of pure CuO nanoparticles is relatively limited, while the noble metal Pt, although possessing high catalytic activity, is prone to aggregation and is costly. To overcome the performance bottleneck of single materials, researchers have discovered that constructing heterogeneous nanocomposites from two or more components with synergistic effects is an effective strategy to enhance enzyme-like activity. Against this backdrop, CuO-Pt nanocomposites have emerged and quickly become a research hotspot in the field of H2O2 colorimetric sensing. In this nanocomposite material, there is an electronic synergistic effect between CuO and Pt. The high conductivity and catalytic activity of Pt, combined with the abundant active sites and unique electronic structure of CuO, accelerate electron transfer and promote the decomposition of H2O2 into highly reactive hydroxyl radicals, thereby significantly accelerating the oxidation rate of TMB. CuO-Pt nanocomposites exhibit a low Michaelis constant and a high catalytic rate constant, demonstrating strong affinity and rapid catalytic conversion efficiency for the substrates H₂O₂ and TMB. Combining the abundant resources of transition metal oxides with the highly efficient catalytic properties of noble metals, CuO-Pt nanocomposites significantly improve the detection performance of H₂O₂ through a synergistic effect. They not only overcome the instability of natural enzymes but also compensate for the insufficient catalytic efficiency of single nanomaterials, showcasing a comprehensive advantage of rapid response, ease of operation, and low cost, and have broad application prospects in biomedicine, food safety, and environmental monitoring. Summary of the Invention

[0005] This invention provides a method for preparing CuO-Pt nanocomposite materials, which enables quantitative detection of H2O2 concentration.

[0006] To achieve the above objectives, the present invention provides the following technical solution: Step (1): Weigh a certain amount of copper chloride dihydrate, dissolve it in a certain volume of deionized water, set a certain reaction temperature, add a certain volume of sodium hydroxide aqueous solution of a certain concentration, and stir for a period of time.

[0007] Step (2): Add a certain volume and concentration of ascorbic acid aqueous solution and continue stirring for a period of time.

[0008] Step (3): Add a certain volume and concentration of sodium chloroplatinate aqueous solution, continue stirring for a period of time, and then cool down naturally. Wash the obtained product by centrifugation with deionized water and anhydrous ethanol several times, and then transfer it to a vacuum oven to dry. Then put the obtained sample into a tube furnace and keep it at a certain reaction temperature for a period of time. After cooling down naturally, take it out from the tube furnace to obtain CuO-Pt nanocomposite material.

[0009] Preferably, in step (1), the amount of copper chloride dihydrate used is 0.8~1.2 mmol, the volume of deionized water is 90~110 mL, the reaction temperature is 50~60 ℃, the volume of sodium hydroxide aqueous solution is 9~12 mL, the concentration of sodium hydroxide aqueous solution is 1.8~2 mol / L, the dropping rate is 0.05~0.1 mL / s, and the stirring time is 0.5~1 h.

[0010] Preferably, in step (2), the volume of the ascorbic acid aqueous solution is 9~12 mL, the concentration of the ascorbic acid aqueous solution is 0.5~0.7 mol / L, the dropping rate is 0.1~0.15 mL / s, and the stirring time is 3~4 h.

[0011] Preferably, in step (3), the volume of the sodium chloroplatinate aqueous solution is 50~60 μL, the concentration of the sodium chloroplatinate aqueous solution is 0.4~0.6 g / mL, the stirring time is 0.2~0.5 h, the reaction temperature in the tube furnace is 350~400℃, and the heat preservation time in the tube furnace is 2~4 h.

[0012] The advantages and beneficial effects of this invention are: 1. This invention provides a method for preparing CuO-Pt nanocomposite materials. In this nanocomposite material, there is an electronic synergistic effect between CuO and Pt materials. The high conductivity and catalytic activity of Pt combined with the abundant active sites and unique electronic structure of CuO accelerates electron transfer and promotes the decomposition of H2O2 into highly active hydroxyl radicals, thereby significantly accelerating the oxidation rate of TMB.

[0013] 2. This invention provides a method for preparing CuO-Pt nanocomposite materials. These nanocomposite materials combine the abundant resources of transition metal oxides with the efficient catalytic properties of noble metals. Through a synergistic effect, they significantly improve the detection performance of H2O2 and exhibit comprehensive advantages such as rapid response, simple operation, and low cost. Attached Figure Description

[0014] Figure 1 : A flowchart of a method for preparing CuO-Pt nanocomposite materials proposed in this invention; Figure 2 X-ray powder diffraction patterns of CuO-Pt nanocomposites obtained in Examples 1, 2, and 3 of this invention; Figure 3 X-ray photoelectron spectrum of Pt element in CuO-Pt nanocomposite material obtained in Example 1 of this invention; Figure 4 Scanning electron microscope images of the CuO-Pt nanocomposites obtained in Examples 1, 2, and 3 of this invention; Figure 5 Transmission electron microscopy image of the CuO-Pt nanocomposite material obtained in Example 1 of this invention; Figure 6 The response performance of CuO-Pt nanocomposites obtained in Examples 1, 2, and 3 of this invention to H2O2; Figure 7 : Detection range of H2O2 for the CuO-Pt nanocomposite material obtained in Example 1 of this invention. Detailed Implementation

[0015] The present invention will be described in detail below with reference to the embodiments, but the scope of protection of the present invention is not limited to the following embodiments. Example 1:

[0016] Step (1): Weigh 1.0 mmol of copper chloride dihydrate, dissolve it in 100 mL of deionized water, set the reaction temperature to 55 ℃, add 10 mL of 2.0 mol / L sodium hydroxide aqueous solution at a dropping rate of 0.05 mL / s, and stir for 0.5 h.

[0017] Step (2): Add 10 mL of 0.6 mol / L ascorbic acid aqueous solution at a dropping rate of 0.1 mL / s, and continue stirring for 3 h.

[0018] Step (3): Add 55 μL of 0.5 g / mL sodium chloroplatinate aqueous solution, continue stirring for 0.5 h, and allow to cool naturally. Wash the obtained product by centrifugation with deionized water and anhydrous ethanol several times, and then transfer it to a vacuum oven to dry. Then place the obtained sample in a tube furnace and keep it at 400 ℃ for 3 h. After cooling naturally, take it out of the tube furnace to obtain CuO-Pt nanocomposite material. Example 2:

[0019] Step (1): Weigh 1.0 mmol of copper chloride dihydrate, dissolve it in 100 mL of deionized water, set the reaction temperature to 55 ℃, add 10 mL of 2.0 mol / L sodium hydroxide aqueous solution at a dropping rate of 0.05 mL / s, and stir for 0.5 h.

[0020] Step (2): Add 10 mL of 0.6 mol / L ascorbic acid aqueous solution at a dropping rate of 0.1 mL / s, and continue stirring for 3 h.

[0021] Step (3): Add 50 μL of sodium chloroplatinate aqueous solution at 0.6 g / mL, continue stirring for 0.3 h, and allow to cool naturally. Wash the obtained product by centrifugation with deionized water and anhydrous ethanol multiple times, and then transfer it to a vacuum oven to dry. Subsequently, place the obtained sample in a tube furnace and keep it at 400 ℃ for 3 h. After cooling naturally, remove it from the tube furnace to obtain CuO-Pt nanocomposite material. Example 3:

[0022] Step (1): Weigh 1.0 mmol of copper chloride dihydrate, dissolve it in 100 mL of deionized water, set the reaction temperature to 55 ℃, add 10 mL of 2.0 mol / L sodium hydroxide aqueous solution at a dropping rate of 0.05 mL / s, and stir for 0.5 h.

[0023] Step (2): Add 10 mL of 0.6 mol / L ascorbic acid aqueous solution at a dropping rate of 0.1 mL / s, and continue stirring for 3 h.

[0024] Step (3): Add 60 μL of sodium chloroplatinate aqueous solution (0.4 g / mL), continue stirring for 0.4 h, and allow to cool naturally. Wash the obtained product by centrifugation with deionized water and anhydrous ethanol multiple times, then transfer it to a vacuum oven to dry. Subsequently, place the obtained sample in a tube furnace and keep it at 400 ℃ for 3 h. After cooling naturally, remove it from the tube furnace to obtain CuO-Pt nanocomposite material.

[0025] While the specific embodiments of the present invention have been described above in conjunction with examples, they are not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for preparing CuO-Pt nanocomposite material, characterized in that, Includes the following steps: Step 1: Weigh a certain amount of copper chloride dihydrate, dissolve it in a certain volume of deionized water, set a certain reaction temperature, add a certain volume of sodium hydroxide aqueous solution of a certain concentration, and stir for a period of time. Step 2: Add a certain volume and concentration of ascorbic acid aqueous solution, and continue stirring for a period of time; Step 3: Add a certain volume and concentration of sodium chloroplatinate aqueous solution, continue stirring for a period of time, and allow it to cool naturally. Wash the obtained product by centrifugation multiple times with deionized water and anhydrous ethanol, and then transfer it to a vacuum oven to dry. Subsequently, place the obtained sample into a tube furnace and keep it at a certain reaction temperature for a period of time. After cooling naturally, remove it from the tube furnace to obtain CuO-Pt nanocomposite material.

2. The method for preparing a CuO-Pt nanocomposite material according to claim 1, characterized in that: In step one, the amount of copper chloride dihydrate used is 0.8~1.2 mmol, the volume of deionized water is 90~110 mL, the reaction temperature is 50~60 ℃, the volume of sodium hydroxide aqueous solution is 9~12 mL, the concentration of sodium hydroxide aqueous solution is 1.8~2 mol / L, the dropping rate is 0.05~0.1 mL / s, and the stirring time is 0.5~1 h.

3. The method for preparing a CuO-Pt nanocomposite material according to claim 1, characterized in that: In step two, the volume of the ascorbic acid aqueous solution is 9-12 mL, the concentration of the ascorbic acid aqueous solution is 0.5-0.7 mol / L, the dropping rate is 0.1-0.15 mL / s, and the stirring time is 3-4 h.

4. The method for preparing a CuO-Pt nanocomposite material according to claim 1, characterized in that: In step three, the volume of the sodium chloroplatinate aqueous solution is 50-60 μL, the concentration of the sodium chloroplatinate aqueous solution is 0.4-0.6 g / mL, the stirring time is 0.2-0.5 h, the reaction temperature in the tube furnace is 350-400 ℃, and the holding time in the tube furnace is 2-4 h.

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