A MnO-based 2 -Co / rGO-CNT self-supporting flexible hydrogen peroxide sensor electrode material and its application
By growing MnO2-Co/rGO-CNT electrode material in situ on the rGO-CNT film, the problem of electrode material separation in the process of mechanical deformation of flexible sensors is solved, and the catalytic performance is improved through the synergistic effect of Co and MnO2, which is achieved. Hydrogen peroxide has high sensitivity detection and anti-interference ability, suitable for live cell detection.
Patent Information
- Application Number
- CN202211103266.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-09-09
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2042-09-09
AI Technical Summary
The existing flexible sensors tend to cause separation of the electrode material and the substrate during mechanical deformation, reducing their electrochemical properties, and the poor conductivity of MnO2 as a hydrogen peroxide sensor electrode limits its catalytic ability.
The 3D porous nanoflower-like MnO2 and nanosphere-like Co are grown in situ on the homemade rGO-CNT film by constant potential deposition method to form MnO2-Co/rGO-CNT self-supported flexible hydrogen peroxide sensor electrode material, using Co and MnO2 Synergistic effects improve catalytic performance and improve conductivity by reducing the accumulation of graphene oxide and introducing carbon nanotubes.
It realizes excellent electrochemical catalytic activity and high sensitivity detection of hydrogen peroxide, has good anti-interference ability and deformation resistance, and is suitable for real-time hydrogen peroxide detection in living cells.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention belongs to the field of electrochemical sensor electrode materials, and particularly relates to an electrochemical sensor electrode material based on MnO 2 -Co / rGO-CNT self-supporting flexible hydrogen peroxide sensor electrode materials and applications. Background Art
[0002] In recent years, with the rapid development of sensing technology, flexible sensors with good flexibility, good wearability, strong portability, and light weight have shown broad application prospects in the fields of health and medical monitoring, human motion monitoring, and artificial intelligence, and have become one of the world's cutting-edge research directions. However, most of the current flexible sensors use flexible substrates as deformation carriers. During the mechanical deformation process, the flexible substrate is the main stress-bearing part. When folded or bent, it is easy to cause the electrode material and the substrate to separate, seriously reducing its electrochemical performance. Therefore, the development of flexible self-supporting electrochemical sensors has become one of the current research hotspots.
[0003] As we all know, the key to flexible self-supporting electrochemical sensors lies in flexible electrode materials. Therefore, the fundamental way to solve the above problems is to develop flexible self-supporting electrode materials that do not require the use of binders and conductive additives, and to use the inherent flexibility of electrode materials to achieve high flexibility of flexible sensors. So far, transition metal oxides of different morphologies have been widely used for the detection of hydrogen peroxide, such as one-dimensional MnO 2 Nanowires and 2D MnO 2 Nanosheets. But one-dimensional and two-dimensional MnO 2 The surface area is small, the active sites are also few, and the catalytic ability needs to be further improved. Some 3D structures, such as nano-spherical MnO 2 and nanoflower-like MnO 2 There will be more exposed surfaces, thus providing more active sites and showing greater advantages in the catalysis of hydrogen peroxide. 2 The inherent poor conductivity has become the main obstacle limiting its use as a hydrogen peroxide sensing electrode. Research results show that compared with active materials based on single metal oxides, composite nanomaterials composed of two or more nanoparticles have higher competitiveness as active materials for catalyzing hydrogen peroxide, that is, the synergistic effect can improve the catalytic performance of electrode materials. According to research, Co has excellent catalytic performance and excellent conductivity, and combined with metal oxides to obtain highly conductive nanohybrid materials. Therefore, Co and MnO 2 Combining and constructing composite materials to form a synergistic effect can maximize the catalytic performance of electrode materials. 2 -Co is reported to be used in flexible hydrogen peroxide sensing electrodes.
[0004] Graphene oxide has become a research hotspot for self-supporting flexible materials due to its large specific surface area, high mechanical strength and chemical stability. However, graphene oxide has the disadvantages of easy stacking and poor hydrophilicity, which hinders its further application in electrochemical research. Compared with graphene oxide, reduced graphene oxide contains fewer oxygen groups and has better hydrophilicity and conductivity. Therefore, introducing carbon nanotubes as interlayer supports in graphene oxide films can reduce the stacking of graphene oxide and further partially reduce it, so as to obtain reduced graphene oxide-carbon nanotubes with stable performance and higher conductivity.
[0005] In summary, the present invention breaks through the bottleneck that traditional flexible electrodes require elastic substrates, conductive additives and binders, and uses constant potential deposition to make the active sensing material MnO 2 -Co was in situ grown on the surface of the self-supporting flexible film rGO-CNT to prepare the self-supporting flexible hydrogen peroxide sensor electrode material, namely MnO 2 -Co / rGO-CNT. The electrode material has excellent flexibility and exhibits excellent electrochemical catalytic activity for hydrogen peroxide. It can also be used for real-time in situ detection of hydrogen peroxide released by living cells. Summary of the invention
[0006] The purpose of the present invention is to provide a MnO-based 2 -Co / rGO-CNT self-supporting flexible hydrogen peroxide sensor electrode material and application. The specific invention content is:
[0007] 1. A MnO-based 2 -Self-supported flexible hydrogen peroxide sensor electrode materials and applications of Co / rGO-CNT, 3D porous nanoflower-like MnO composed of nanorods 2 The nano-spherical Co with a diameter of about 120 nm and an uneven surface is in situ grown on the rGO-CNT film to form a self-supporting flexible hydrogen peroxide sensor electrode material. The preparation method is as follows: the self-supporting flexible composite film rGO-CNT is used as the working electrode, the Ag / AgCl electrode is used as the reference electrode, and the platinum wire electrode is used as the counter electrode. 2 SO 4 and MnSO 4 The electroplating time was 300s to 1000s in a 0.05M to 0.2M electrolyte solution, and the deposition potential was 0.5V to 2.0V. The MnO was washed with deionized water and dried at room temperature to obtain the MnO 2 / rGO-CNT. To obtain MnO 2 / rGO-CNT was used as the working electrode in the presence of 1 M Na 2 SO 4 、0.5MH 3 BO3 and CoCl 2 The solution was prepared by constant potential method, the deposition potential was -1.05V to -1.45V, the electrodeposition time was 38s to 180s, and the solution was washed with deionized water and dried at room temperature to obtain MnO 2 -Co / rGO-CNT self-supporting flexible hydrogen peroxide sensor electrode material.
[0008] 2. Applying the electrochemical workstation to obtain the self-supporting flexible hydrogen peroxide sensor electrode material MnO 2 -Co / rGO-CNT is the working electrode, platinum wire electrode is the counter electrode, and saturated calomel electrode is the reference electrode. A three-electrode system is used. Under stirring, in a 0.2M PBS solution (pH=7.4), the working potential is controlled to be -0.55V. After the background current is stable, the current-time curve (it) after adding different concentrations of hydrogen peroxide is tested, and its detection range, detection limit, and sensitivity are obtained by calculation. The electrode material has a good current response to hydrogen peroxide, and the detection range is as wide as 0.0004mmol·L -1 ~18.0mmol·L -1 , detection limit as low as 66.7nmol·L -1 , sensitivity as high as 159.4μA·mmol -1 It has strong anti-interference ability, good stability, reproducibility and repeatability, and excellent anti-deformation ability, and can be used for real-time detection of hydrogen peroxide released by living cells. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 The self-supporting flexible hydrogen peroxide sensor electrode material MnO prepared in Example 1 2 -SEM images of Co / rGO-CNT;
[0010] Figure 2 The self-supporting flexible hydrogen peroxide sensor electrode material MnO prepared in Example 1 2 -Current-time response curve of Co / rGO-CNT to hydrogen peroxide;
[0011] Figure 3 The self-supporting flexible hydrogen peroxide sensor electrode material MnO prepared in Example 1 2 -The current-time response curves of Co / rGO-CNT to hydrogen peroxide and interfering substances ascorbic acid (AA), dopamine (DA), glucose (Glucose) and sodium chloride (NaCl);
[0012] Figure 4 The self-supporting flexible hydrogen peroxide sensor electrode material MnO prepared in Example 12 -Current response of Co / rGO-CNT to hydrogen peroxide before and after twisting 100 times;
[0013] Figure 5 The self-supporting flexible hydrogen peroxide sensor electrode material MnO prepared in Example 1 2 -Co / rGO-CNT in the presence and absence of MCF-7 cells with 200 mg mL -1 Current response in 0.2 M PBS (pH=7.4) solution of AA. DETAILED DESCRIPTION
[0014] The present invention is further described in detail below with reference to specific examples, but these examples do not limit the scope of the present invention in any way.
[0015] Example 1
[0016] (1) The self-made flexible composite film rGO-CNT was used as the working electrode, the Ag / AgCl electrode was used as the reference electrode, and the platinum wire electrode was used as the counter electrode. 2 SO 4 and 0.1M MnSO 4 The electroplating potential was 1.0 V and the MnO was obtained by electroplating for 600 s. The MnO was washed with deionized water and dried at room temperature. 2 / rGO-CNT.
[0017] (2) MnO obtained in step (1) 2 / rGO-CNT was used as the working electrode in the presence of 1 M Na 2 SO 4 、0.5MH 3 BO 3 and 0.01 M CoCl 2 The MnO was obtained by electroplating for 120 s in a solution of 1.15 V using a constant potential method and washing with deionized water and drying at room temperature. 2 -Co / rGO-CNT self-supporting flexible hydrogen peroxide sensor electrode material. See the attached SEM photo Figure 1 From the attached Figure 1 It can be seen that MnO 2 It presents a 3D porous nanoflower shape composed of nanorods. Co is a nanosphere with an uneven surface and a diameter of about 120nm. The nanoflower-shaped MnO 2 The nano-spherical Co is evenly distributed on the rGO-CNT, and this special morphology gives it a larger specific surface area and more active sites for catalyzing hydrogen peroxide.
[0018] (3) Using the self-supporting flexible hydrogen peroxide sensor electrode material MnO obtained in step (2) 2 -Co / rGO-CNT was used as the working electrode, saturated calomel electrode as the reference electrode, and platinum wire electrode as the counter electrode. Under stirring, the working potential was controlled to -0.55 V in 0.2 M PBS (pH = 7.4) solution. After the background current was stable, the MnO 2 -The current-time curve of Co / rGO-CNT in response to different concentrations of hydrogen peroxide. The results are shown in the attached Figure 2 . Figure 2 It can be seen that MnO 2 -Co / rGO-CNT responds quickly to hydrogen peroxide, and current equilibrium can be reached in a very short time after adding hydrogen peroxide. 2 -The detection range of Co / rGO-CNT for hydrogen peroxide is 0.0004mmol·L -1 ~18.0mmol·L -1 , the detection limit was 66.7nmol·L -1 , sensitivity is 159.4μA·mmol -1 .
[0019] (4) Using the self-supporting flexible hydrogen peroxide sensor electrode material MnO obtained in step (2) 2 -Co / rGO-CNT was used as the working electrode, saturated calomel electrode as the reference electrode, and platinum wire electrode as the counter electrode. Under stirring, the working potential was controlled to -0.55 V in 0.2 M PBS (pH = 7.4) solution. After the background current was stable, the MnO 2 -The current-time curves of Co / rGO-CNT in response to hydrogen peroxide and interfering substances ascorbic acid (AA), dopamine (DA), glucose (Glucose) and sodium chloride (NaCl). The results are shown in the attached Figure 3 . Figure 3 It can be seen that MnO 2 -Co / rGO-CNT has good selectivity for hydrogen peroxide.
[0020] (5) Self-supporting flexible hydrogen peroxide sensor electrode material MnO before and after twisting 180° and 100 times 2 -Co / rGO-CNT was used as the working electrode, saturated calomel electrode as the reference electrode, and platinum wire electrode as the counter electrode. Under stirring, the working potential was controlled to -0.55 V in 0.2 M PBS (pH = 7.4) solution. After the background current was stable, the MnO 2 -The current-time curve of Co / rGO-CNT response to hydrogen peroxide, the results are attached Figure 4 . Figure 4It can be seen that after 100 twists, MnO 2 -Co / rGO-CNT current response to hydrogen peroxide remains almost unchanged, indicating that MnO 2 -Co / rGO-CNT has good flexibility.
[0021] (6) Using the self-supporting flexible hydrogen peroxide sensor electrode material MnO obtained in step (2) 2 -Co / rGO-CNT was used as the working electrode, saturated calomel electrode was used as the reference electrode, and platinum wire electrode was used as the counter electrode. 6 The stimulant AA was added to the 0.2M PBS (pH = 7.4) solution of MCF-7 cells, and the working potential was controlled to -0.55V. After the background current stabilized, the MnO 2 -The current-time curve of Co / rGO-CNT in response to hydrogen peroxide released by MCF-7 cells. At the same time, a comparative experiment was conducted under the same conditions. The results are shown in the attached Figure 5 . Figure 5 It can be seen that in the 0.2M PBS (pH = 7.4) solution without MCF-7 cells, the current response did not change when AA was added, but in the 0.2M PBS (pH = 7.4) solution with MCF-7 cells, the current response changed significantly when AA was added, indicating that MnO 2 -Co / rGO-CNT can be used to monitor hydrogen peroxide released by cancer cells in real time.
[0022] The above descriptions are merely embodiments of the electrode material of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A self-supporting flexible hydrogen peroxide sensor electrode material based on MnO2-Co / rGO-CNT, characterized in that: A 3D porous nanoflower-like MnO2 composed of nanorods and a nanosphere-like Co with a diameter of 120 nm and an uneven surface are in situ grown on the rGO-CNT film to form a self-supporting flexible hydrogen peroxide sensor electrode material. The preparation method is as follows: using the self-supporting flexible composite film rGO-CNT as the working electrode, the Ag / AgCl electrode as the reference electrode, and the platinum wire electrode as the counter electrode, in an electrolyte containing 0.1M Na2SO4 and 0.1M MnSO4, a constant potential method is used, the deposition potential is selected to be 1.0V, the electrodeposition is performed for 600s, and the MnO2 / rGO-CNT is washed with deionized water and then dried at room temperature; the obtained MnO2 / rGO-CNT is used as the working electrode, and in an electrolyte containing 1MNa2SO4, 0.5M H3BO3 and 0.01M In a CoCl2 solution, a constant potential method was used, the deposition potential was selected to be -1.15 V, the electrodeposition was performed for 120 s, the material was washed with deionized water and dried at room temperature to obtain the MnO2-Co / rGO-CNT self-supporting flexible hydrogen peroxide sensor electrode material.
2. The use of a self-supporting flexible hydrogen peroxide sensor electrode material based on MnO2-Co / rGO-CNT as claimed in claim 1, characterized in that: The electrode material has a good current response to hydrogen peroxide and a detection range as wide as 0.0004 mmol·L -1 ~18.0mmol·L -1 , the detection limit is as low as 66.7nmol·L -1 , sensitivity as high as 159.4μA·mmol -1 It has strong anti-interference ability, good stability, reproducibility and repeatability, and excellent anti-deformation ability, and can be used for real-time detection of hydrogen peroxide released by living cells.