Preparation Method of Composite Structure Au@Cu2O / Cu(OH)2
The particle/line composite structure of copper-based nanomaterial Au@Cu2O/Cu(OH)2 was prepared by the liquid phase method, which solved the problem of cumbersome preparation process in the prior art and achieved efficient sensing performance.
Patent Information
- Application Number
- CN202211119210.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-09-13
- Publication Date
- 2025-08-05
- Estimated Expiration
- 2042-09-13
AI Technical Summary
The prior art is difficult to simply and efficiently prepare the particle/line composite structure of the copper-based nanomaterial Cu2O/Cu(OH)2. The synthesis process is cumbersome and the reaction conditions are limited, resulting in poor charge response performance.
The composite structure Au@Cu2O/Cu(OH)2 was prepared by liquid phase method. By adding gold nanorods, NaOH and N2H4·H2O and other substances to ultrapure water, the stirring speed and time were controlled, and centrifugation and vacuum drying were performed to obtain a particle/line composite structure.
The process is simple and controllable. The prepared composite structure Au@Cu2O/Cu(OH)2 has high efficiency mass-transfer and load transfer performance, significantly improving the enzyme-free glucose sensing performance.
Smart Images
Figure CN115494128B_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of electrode materials, and particularly relates to a preparation method of a composite structure Au@Cu2O / Cu(OH)2. Background Art
[0002] In recent years, the trend of semiconductor devices has gradually developed towards the nanoscale. The functions of single nanomaterials are far from meeting the rapidly growing demands. Therefore, the current research direction has gradually shifted to multi-level nanomaterials. Through the mutual synergistic effects or special structural morphologies between different components, multi-level nanomaterials can effectively improve their glucose sensing performance.
[0003] Copper has two natural oxides: cuprous oxide and copper oxide, both of which are semiconductors with band gaps of 2.2 eV and 1.2 eV respectively. Copper-based semiconductor nanomaterials have attracted much attention due to their advantages such as simple production, low cost, and non-toxicity. Their preparation methods include liquid phase method, solid phase method, and gas phase method. Most of the existing preparation methods of Cu2O / Cu(OH)2 are electrochemical deposition methods, but the morphologies of the prepared composites are all nanoparticles. The charge response performance of nanoparticles is not as good as that of particle / wire composite structures. The existing methods for preparing particle / wire composite structures are extreme oxidation method, hydrothermal method, atomic deposition method, etc. Usually, one of the materials is first prepared and then the other material is compounded. The synthesis process is very cumbersome and the reaction conditions are restricted more. Summary of the Invention
[0004] The purpose of the present invention is to provide a preparation method of a composite structure Au@Cu2O / Cu(OH)2, which can simply and efficiently prepare the composite structure Au@Cu2O / Cu(OH)2 nanomaterials.
[0005] The technical solution adopted by the present invention is a preparation method of a composite structure Au@Cu2O / Cu(OH)2. Dissolve Cu(NO3)2·3H2O and SDS in ultrapure water; add gold nanorods and stir; stir the solution at a low speed, and at the same time add NaOH and stir for 10 min to 30 min; then stir the solution at a high speed, and at the same time add N2H4·H2O and stir for 30 min to 60 min; perform centrifugation to collect the reactants, and then perform vacuum drying treatment on the reactants.
[0006] The present invention is further characterized in that
[0007] The temperature of the ultrapure water is 27°C to 33°C, and the resistivity of the ultrapure water is 18 MΩ·cm to 19 MΩ·cm.
[0008] The ratio of the added gold nanorods to Cu in the solution is, gold nanorods: Cu 2+ 2+ = 1:400 to 700, and the stirring time is 1 min to 2 min after adding gold nanorods.
[0009] The rotation speed of low-speed stirring is 50 rpm to 250 rpm.
[0010] The ratio of NaOH to Cu in the solution 2+ is, NaOH:Cu 2+ = 1:0.01 to 0.05.
[0011] The rotation speed of high-speed stirring is 700 rpm to 1000 rpm.
[0012] The concentration of N2H4·H2O is 0.00035 mol / L to 0.0175 mol / L, and the ratio of N2H4·H2O to Cu in the solution 2+ is, N2H4·H2O:Cu 2+ = 7:2 to 10.
[0013] When centrifuging, the centrifugal rotation speed is 7000 rpm to 8000 rpm, and the centrifugal time is 3 min to 8 min.
[0014] The drying temperature of vacuum drying is 30 °C to 35 °C, the drying time is 5 h to 7 h, and the vacuum degree of vacuum drying is 0.001 pa to 0.9 pa.
[0015] The beneficial effects of the present invention are
[0016] The preparation method of the present invention has the advantages of simple process and controllable operation, and the prepared composite structure Au@Cu2O / Cu(OH)2 has the characteristics of high mass transfer and charge transfer performance, greatly improving the sensing performance of enzyme-free glucose. Brief Description of the Drawings
[0017] Figure 1 is the SEM image of Au@Cu2O / Cu(OH)2 obtained by the preparation method of the present invention;
[0018] Figure 2 is the X-ray diffraction pattern of Au@Cu2O / Cu(OH)2 obtained by the preparation method of the present invention;
[0019] Figure 3 is the cyclic voltammogram of Au@Cu2O / Cu(OH)2 obtained by the preparation method of the present invention, Comparative Example 1 and Comparative Example 2 in 1 mM glucose;
[0020] Figure 4 is the chronoamperogram of Au@Cu2O / Cu(OH)2 obtained by the preparation method of the present invention, Comparative Example 1 and Comparative Example 2 in 1 mM glucose;
[0021] Figure 5 The electrochemical impedance spectrograms of Au@Cu2O / Cu(OH)2 obtained by the preparation method of the present invention and Comparative Example 1 and Comparative Example 2. Detailed Description of the Invention
[0022] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.
[0023] In the preparation method of the composite structure Au@Cu2O / Cu(OH)2 of the present invention, Cu(NO3)2·3H2O as a copper source and SDS as a reducing agent are dissolved in ultrapure water at a temperature of 27°C to 33°C, and the resistivity of the ultrapure water is 18 MΩ·cm to 19 MΩ·cm; then gold nanorods are added to the prepared solution, and the ratio of the added gold nanorods to Cu in the solution is 2+ gold nanorods: Cu 2+ = 1:400 to 700, and stirred for 1 min to 2 min; the solution is stirred at a speed of 50 rpm to 250 rpm, and at the same time, NaOH is added, and the ratio of NaOH to Cu in the solution is 2+ NaOH: Cu 2+ = 1:0.01 to 0.05, and stirred for 10 min to 30 min;
[0024] Then the solution is stirred at a speed of 700 rpm to 1000 rpm, and at the same time, N2H4·H2O is added, the added concentration of N2H4·H2O is 0.00035 mol / L to 0.0175 mol / L, and the ratio of N2H4·H2O to Cu in the solution is 2+ N2H4·H2O: Cu 2+ = 7:2 to 10, and stirred for 30 min to 60 min; the obtained solution is centrifuged to collect the reactants, the centrifugation speed is 7000 rpm to 8000 rpm, and the centrifugation time is 3 min to 8 min. If the reactants in the solution cannot be completely centrifuged and separated in a single time, centrifugation can be repeated multiple times until there are no obvious reactants in the solution, and then the reactants are subjected to vacuum drying treatment. The drying temperature of the vacuum drying is 30°C to 35°C, the drying time is 5 h to 7 h, and the vacuum degree of the vacuum drying is 0.001 Pa to 0.9 Pa.
[0025] The preparation method of the present invention has the advantages of simple process and controllable operation, and the prepared composite structure Au@Cu2O / Cu(OH)2 has the characteristics of high-efficiency mass transfer and charge transfer performance, which greatly improves the sensing performance of enzyme-free glucose. As Figure 1 shown, the prepared Au@Cu2O / Cu(OH)2 has a composite structure of particles / wires. The nanoparticles are composed of octahedral Cu2O coating Au nanoparticles, and the nanowires are composed of Cu(OH)2.
[0026] Example 1
[0027] The copper source Cu(NO3)2·3H2O and the reducing agent SDS were dissolved in ultrapure water at a temperature of 27°C. The resistivity of ultrapure water was 18MΩ·cm. Then gold nanorods were added to the prepared solution. The added gold nanorods reacted with the Cu in the solution. 2+ The ratio of gold nanorods: Cu 2+ =1:400, and stir for 1 min; stir the solution at 50 rpm, and add NaOH at the same time, NaOH and Cu 2+ The ratio is NaOH:Cu 2+ =1:0.01, stirring for 10 minutes;
[0028] Then the solution was stirred at 700 rpm and N2H4·H2O was added at a concentration of 0.00035 mol / L. N2H4·H2O reacted with Cu in the solution. 2+ The ratio is N2H4·H2O:Cu 2+ =7:2, stirred for 30min; the obtained solution was centrifuged to collect the reactants, the centrifugal speed was 7000rpm, the centrifugal time was 3min, the centrifugal treatment was repeated 3 times, and the reactants were vacuum dried at a drying temperature of 30°C, a drying time of 5h, and a vacuum degree of 0.001pa.
[0029] Example 2
[0030] The copper source Cu(NO3)2·3H2O and the reducing agent SDS were dissolved in ultrapure water at a temperature of 30°C. The resistivity of ultrapure water was 18.2MΩ·cm. Then gold nanorods were added to the prepared solution. The added gold nanorods reacted with the Cu in the solution. 2+ The ratio of gold nanorods: Cu 2+ =1:500 and stirred for 1.5min; stirred the solution at 100rpm and added NaOH at the same time. NaOH and Cu 2+ The ratio is NaOH:Cu 2+ =1:0.02, stirring for 20 minutes;
[0031] Then the solution was stirred at 800 rpm and N2H4·H2O was added at a concentration of 0.005 mol / L. N2H4·H2O reacted with Cu in the solution. 2+ The ratio is N2H4·H2O:Cu 2+= 7:7, stir for 50 min; centrifuge the resulting solution to collect the reactants, with a centrifuge speed of 7500 rpm and a centrifuge time of 6 min. If the reactants in the solution cannot be completely centrifuged and separated in a single time, centrifugation can be repeated multiple times until there are no obvious reactants in the solution, and then vacuum drying treatment is carried out on the reactants. The drying temperature for vacuum drying is 32 °C, the drying time is 6 h, and the vacuum degree for vacuum drying is 0.01 pa.
[0032] Example 3
[0033] Dissolve Cu(NO3)2·3H2O as the copper source and SDS as the reducing agent in ultrapure water at a temperature of 31 °C. The resistivity of the ultrapure water is 18.6 MΩ·cm; then add gold nanorods to the prepared solution. The ratio of the added gold nanorods to Cu in the solution is 2+ Gold nanorods: Cu 2+ = 1:600, and stir for 1.8 min; stir the solution at a speed of 150 rpm, and at the same time add NaOH. The ratio of NaOH to Cu in the solution is 2+ NaOH: Cu 2+ = 1:0.03, stir for 25 min;
[0034] Then stir the solution at a speed of 900 rpm, and at the same time add N2H4·H2O. The concentration of the added N2H4·H2O is 0.01 mol / L. The ratio of N2H4·H2O to Cu in the solution is 2+ N2H4·H2O: Cu 2+ = 7:8, stir for 45 min; centrifuge the resulting solution to collect the reactants, with a centrifuge speed of 7200 rpm and a centrifuge time of 7 min. If the reactants in the solution cannot be completely centrifuged and separated in a single time, centrifugation can be repeated multiple times until there are no obvious reactants in the solution, and then vacuum drying treatment is carried out on the reactants. The drying temperature for vacuum drying is 33 °C, the drying time is 5.5 h, and the vacuum degree for vacuum drying is less than 0.05 pa.
[0035] Example 4
[0036] Dissolve Cu(NO3)2·3H2O as the copper source and SDS as the reducing agent in ultrapure water at a temperature of 33 °C. The resistivity of the ultrapure water is 19 MΩ·cm; then add gold nanorods to the prepared solution. The ratio of the added gold nanorods to Cu in the solution is 2+ Gold nanorods: Cu 2+ = 1:700, and stir for 2 min; stir the solution at a speed of 250 rpm, and at the same time add NaOH. The ratio of NaOH to Cu in the solution is 2+ NaOH: Cu 2+ = 1:0.05, stir for 30 min;
[0037] Then, stir the solution at a speed of 1000 rpm, and simultaneously add N2H4·H2O. The concentration of the added N2H4·H2O is 0.0175 mol / L. The ratio of N2H4·H2O to Cu in the solution is 2+ N2H4·H2O:Cu 2+ = 7:10. Stir for 60 min. Centrifuge the obtained solution to collect the reactants. The centrifuge speed is 8000 rpm, and the centrifuge time is 8 min. If the reactants in the solution cannot be completely centrifuged and separated in one time, centrifuge repeatedly until there are no obvious reactants in the solution. Then, perform vacuum drying treatment on the reactants. The drying temperature for vacuum drying is 35°C, the drying time is 7 h, and the vacuum degree for vacuum drying is less than 0.09 Pa.
[0038] As Figure 2 shown, in the product spectrum of Au@Cu2O / Cu(OH)2, the characteristic peaks at 23.8°, 34.1°, and 35.9° correspond to the crystal plane diffraction peaks of Cu(OH)2 at 021, 002, and 111, respectively, which are consistent with the XRD data of the standard card PDF#72-0140. The characteristic peaks at 29.6°, 36.5°, 42.4°, 61.6°, and 73.7° correspond to the crystal planes of 110, 111, 200, 220, and 311, respectively, which are in agreement with the standard card PDF#77-0199 of cubic Cu2O. The characteristic peaks at 38.2° and 77.5° correspond to the 111 and 311 crystal planes of Au, which correspond to the standard card PDF#01-1172. This indicates that the particle / line composite structure Au@Cu2O / Cu(OH)2 prepared by this method is indeed composed of Au, Cu2O, and Cu(OH)2.
[0039] Comparative Example 1
[0040] Add 0.062 g of copper nitrate and 0.72 g of SDS to ultrapure water. Stir in a water bath at 30°C until all of them are dissolved. Add 100 μL of gold nanorods, stir at a speed of 100 rpm, then add 5 mL of NaOH, continue stirring for 20 min, then stir at a speed of 150 rpm. Add 5 mL of N2H4·H2O during stirring. After continuously stirring for 40 min, then perform centrifugation. The centrifuge speed is 7500 rpm, and the centrifuge time is 5 min. Centrifuge three times to obtain Au@Cu2O.
[0041] Comparative Example 2
[0042] Add 0.062 g of copper nitrate and 0.72 g of SDS to ultrapure water, stir in a water bath at 30 °C until completely dissolved, add 100 μL of gold nanorods, stir at a speed of 900 rpm, then add 5 mL of NaOH, continue stirring for 20 min, then stir at a speed of 1100 rpm, add 5 mL of ultrapure water during stirring, continue stirring for 40 min, and then perform centrifugation. The centrifugation speed is 7500 rpm, the centrifugation time is 5 min, and centrifuge three times to obtain Au@Cu(OH)2.
[0043] To compare the mass transfer and charge transfer performance of the multi-dimensional composite structure materials, the sensing currents of the product modified electrodes prepared by this method and the product modified electrodes obtained in Comparative Example 1 and Comparative Example 2 were compared at a glucose concentration of 1 mM, and the scanning rate was 100 mV / s. As Figure 3 shown, the redox current density in the range of 0.4 V to 0.6 V shows the trend of Au@Cu2O / Cu(OH)2 > Au@Cu2O > Au / Cu(OH)2; as Figure 4 shown, it can be seen from the i-t diagram that the electrodes modified with Au@Cu2O / Cu(OH)2 and Au@Cu2O show a stepped response curve to the gradually increasing glucose concentration, and the response ability of the Au@Cu2O / Cu(OH)2 composite material is the best; both indicate that the Au@Cu2O / Cu(OH)2 multi-dimensional composite structure material protected in this application has better electrocatalytic glucose sensing performance.
[0044] Better understand the charge transfer performance through electrochemical impedance spectroscopy. Usually, the radius of the Nyquist curve of the alternating current impedance spectrum qualitatively reflects the composite rate, where the smaller the radius, the smaller the charge transfer resistance. Select an electrolyte solution of 0.5 M Na2SO4 and perform electrochemical impedance testing in the frequency range of 0.01 Hz to 100 kHz. As Figure 5 shown, the EIS spectra of the product modified electrodes prepared by this method and the product modified electrodes obtained in Comparative Example 1 and Comparative Example 2 are shown. It can be seen from the figure that the impedance spectra all show a single semi-circle, which means that the electrode reaction is controlled by charge transfer. The smaller the radius indicates the smaller the impedance and the faster the charge transfer. Compared with the multi-dimensional structure of mechanically mixed Au@Cu2O / Cu(OH)2, the multi-dimensional composite structure of Au@Cu2O / Cu(OH)2 prepared by chemical liquid phase reduction method has the smallest impedance radius, indicating its fastest charge transfer ability.
Claims
1. A method for preparing a composite structure Au@Cu2O / Cu(OH)2, characterized in that: Dissolve Cu(NO3)2·3H2O and SDS in ultrapure water; Add gold nanorods and stir; The solution was stirred at a low speed while adding NaOH and stirring for 10 to 30 minutes. The solution was then stirred at a high speed while adding N2H4·H2O and stirring for 30 to 60 minutes. The reactants were collected by centrifugation and then vacuum dried. The prepared Au@Cu2O / Cu(OH)2 exhibited a particle / wire composite structure, wherein the nanoparticles were composed of octahedral Cu2O-coated Au nanoparticles, and the nanowires were composed of Cu(OH)2. The low-speed stirring speed is 50 rpm ~ 250 rpm; the high-speed stirring speed is 700 rpm ~ 1000 rpm; The added gold nanorods and Cu in the solution 2+ The ratio of gold nanorods: Cu 2+ =1:400~700, the stirring time after adding the gold nanorods is 1min~2min; The concentration of N2H4·H2O is 0.00035mol / L~0.0175mol / L, and the N2H4·H2O and Cu in the solution 2+ The ratio is N2H4·H2O:Cu 2+ =7:2~10; The drying temperature of the vacuum drying is 30° C. to 35° C., the drying time is 5 h to 7 h, and the vacuum degree of the vacuum drying is 0.001 Pa to 0.9 Pa.
2. The preparation method according to claim 1, characterized in that The temperature of the ultrapure water is 27° C. to 33° C., and the resistivity of the ultrapure water is 18 MΩ•cm to 19 MΩ•cm.
3. The preparation method according to claim 1, characterized in that The NaOH and Cu in the solution 2+ The ratio is NaOH:Cu 2+ =1:0.01~0.
05.
4. The preparation method according to claim 1, characterized in that During the centrifugal treatment, the centrifugal speed is 7000 rpm to 8000 rpm, and the centrifugal time is 3 min to 8 min.