PEDOT-doped MWNTs loaded Au-coated BP5 composite photoelectric material as well as preparation method and application thereof

Abstract

The invention discloses a PEDOT (poly (3, 4-ethylenedioxythiophene))-doped MWNTs (multi-walled carbon nanotubes)-loaded Au-coated BP5 composite photoelectric material and a preparation method and application thereof, the surface of Au NPs is coated with BP5 capable of specifically recognizing HClO, Au-coated BP5 is used as a photoactive material and is loaded on a PEDOT-doped poly (3, 4-ethylenedioxythiophene) composite material PEDOT-MWNTs, and a signal on-off type photoelectrochemical sensing system is designed; au-coated BP5 / PEDOT-MWNTs are used as a sensing material, and HClO is detected by utilizing the local surface plasma effect of gold nanoparticles under visible light illumination, the host-guest complexing effect of asymmetric pillararene BP5 and the reaction of specific groups on pillararene and HClO; the introduced MWNTs serve as a bridge for accelerating transmission of electron carriers, PEDOT is beneficial to faster response due to the wider light absorption range, and the light current response is further improved.

Description

Technical Field

[0001] The invention belongs to the technical field of photoelectrochemistry, and specifically relates to a PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material and a preparation method and application thereof. Background Art

[0002] Hypochlorous acid (HClO) and hypochlorite (ClO - ) is a key reactive oxygen species (ROS) produced in organisms through the catalytic action of myeloperoxidase (MPO). In the immune system, neutrophils produce HClO by combining chloride ions and hydrogen peroxide (H2O2) to fight pathogens in the body. HClO can modify and regulate the functions of a variety of biomolecules, including proteins, lipids, and nucleic acids. This oxidative modification plays a vital role in immune regulation, inflammatory response, and cell signaling. However, due to the strong oxidizing property of HClO, excessive production of HClO may cause oxidative damage to biological tissues, leading to a series of inflammation-related diseases, such as atherosclerosis, neurodegenerative diseases, arthritis, and lung damage. Therefore, rapid and sensitive detection of HClO is of great significance to reveal its physiological and pathological significance.

[0003] In recent years, many analytical methods have been established for the detection of HClO, and these techniques include colorimetric sensors, UV absorption spectroscopy, fluorescent probes, and fluorescence sensors. Among these tools, the photoelectrochemical (PEC) detection technology, which was developed on the basis of traditional electrochemical analysis, has received great attention and recognition. It is known for its strong selectivity, high sensitivity, real-time detection capability, and affordability, making it more cost-effective in the long run. Therefore, analytical techniques based on photoelectrochemical sensors provide a simple method for the detection of HClO by promoting ligand exchange between organic and inorganic molecules.

[0004] Pillar[5]arene is a relatively new class of macrocyclic hosts that has received great attention in the past decade among mature macrocyclic hosts such as crown ethers, cyclodextrins and calixarenes. Due to its simple synthesis, unique rigid columnar structure and π-electron-rich cavity, it is a promising candidate for material construction. The unique inner cavity structure of pillar[5]arene can accommodate small molecules, allowing them to interact with molecules non-covalently (such as hydrogen bonds, van der Waals forces, etc.). This interaction wraps the small molecules to form a stable complex, which enhances the selective recognition ability of photoelectrochemical sensors for surface target molecules. However, its weak electrochemical performance limits its application in the field of electrochemistry. Many researchers have combined the unique structure of macrocyclic supramolecules with the excellent properties of materials such as precious metals, broadening its wide range of applications in fields such as photoelectrochemical sensing.

[0005] Gold nanoparticles (AuNPs) are common metal nanoparticles that are the best candidates for functionalization with pillar[n]arene due to their good tissue compatibility, excellent electron transfer ability, and efficient optical properties. Under visible light, the localized surface plasmon resonance (LSPR) effect of Au NPs and the host-guest complexation of pillar[5]arene allow for highly sensitive and selective detection of molecules.

[0006] Multi-walled carbon nanotubes (MWNTs) and their composites are widely used to design various photoelectrochemical sensors. MWNTs have unique properties such as large specific surface area and high electron transfer capacity, which makes them an excellent alternative support material for dispersing nanoparticles and enhancing electron transfer. Poly (3,4-ethylenedioxythiophene) (PEDOT), as a p-type conducting polymer, has high conductivity, good electrochemical activity and stability, and can accept a large number of photoexcited electrons. Therefore, the preparation of MWNTs doped with PEDOT can avoid the complexation of electron-hole pairs, resulting in comprehensive improvements in conductivity, photocurrent and carriers.

[0007] Therefore, the designed sensitive, stable and low-cost composite optoelectronic material Au@BP5 / PEDOT-MWNTs is expected to have broad application prospects in the determination of HClO. Summary of the invention

[0008] Technical issues solved:

[0009] This application aims at the deficiencies of the prior art and solves the technical problems of low sensitivity, limited detection range, expensive instruments and the like of the original detection technology, and provides a PEDOT-doped MWNTs-loaded Au@BP5 composite optoelectronic material and its preparation method and application.

[0010] Technical solution:

[0011] To achieve the above objectives, this application is implemented through the following technical solutions:

[0012] A method for preparing a PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material, comprising the steps of: doping poly-3,4-ethylenedioxythiophene on multi-walled carbon nanotubes to prepare PEDOT-MWNTs, and then distributing Au@BP5 on the PEDOT-MWNTs to prepare the Au@BP5 / PEDOT-MWNTs composite photoelectric material.

[0013] The first step is to prepare asymmetric pillar aromatic hydrocarbon BP5:

[0014]

[0015] The second step is to prepare a spherical gold nanoparticle solution: using chloroauric acid as a raw material, citric acid and sodium citrate as reducing agents, and using a thermal reduction method to prepare a spherical gold nanoparticle solution, wherein the amount ratio of the chloroauric acid, citric acid and sodium citrate is 1-1.3 mL of 25.4 mM chloroauric acid: 0.9-1.2 mL of 0.1 M citric acid: 2.1-2.8 mL of 0.1 M sodium citrate;

[0016] The third step is to prepare Au@BP5 by ultrasonic method: 5-5.5 mg BP5 is dispersed in 0.5-1 mL DMF to prepare BP5 solution according to mass volume ratio, 0.5-1 mL spherical gold nanoparticle solution is added to the BP5 solution, and Au@BP5 is prepared by ultrasonication for 30-35 min;

[0017] The fourth step is to prepare multi-walled carbon nanotubes MWNTs by covalent modification: first, 1-1.5 mg of multi-walled carbon nanotubes are dispersed in 50 mL of 68% concentrated nitric acid according to a mass volume ratio, and ultrasonic treatment is performed for 30-35 min, and then heated and refluxed in an oil bath at 150-160° C. for 5-6 h, and the obtained product is washed with ultrapure water until the pH reaches 7, and finally freeze-dried to obtain oxidized multi-walled carbon nanotubes MWNTs, and a MWNTs water dispersion system is prepared by oxidized multi-walled carbon nanotubes MWNTs: deionized water = 0.5 mg: 1 mL according to a mass volume ratio;

[0018] Step 5: Preparation of multi-walled carbon nanotubes doped with poly (3,4-ethylenedioxythiophene) PEDOT-MWNTs: First, add 1-2 mL of FeCl3 solution to 1-2 mL of MWNTs aqueous dispersion system by volume, ultrasonicate for 10-15 min, and then add to 2-4 mL of EDOT

[0019] (25 mg / mL) CHCl3 solution, heated at 50-60°C for 12-13 h, the mixture was centrifuged and washed, and dispersed in 10-12 mL of purified water to prepare PEDOT-MWNTs nanohybrid;

[0020] In the sixth step, Au@BP5 / PEDOT-MWNTs was synthesized by physical adsorption method: 2-2.5 mL Au@BP5 was dropped into 1-1.5 mg PEDOT-MWNTs nanohybrid according to the mass-to-volume ratio, and stirred at 600-800 rpm for 5-10 min to obtain Au@BP5 / PEDOT-MWNTs heterojunction, i.e., Au@BP5 / PEDOT-MWNTs composite optoelectronic material.

[0021] Furthermore, the second step of the thermal reduction method to prepare the spherical gold nanoparticle solution is specifically as follows: 0.9-1.2 mL of 0.1 M citric acid and 2.1-2.8 mL of 0.1 M sodium citrate are added to 150-200 mL of boiling water, and stirred at 500-700 rpm for 15-20 min;

[0022] Then add 1-1.3 mL of 25.4 mM chloroauric acid, stir at 500-700 rpm for 3-5 min, and cool in ice water. The obtained precipitate is washed with ultrapure water and ethanol, and the washed precipitate is dispersed in ultrapure water solution to obtain a spherical gold nanoparticle solution.

[0023] Furthermore, the preparation method of the FeCl3 solution in the fifth step is to dissolve 1.62 g of FeCl3 in 10 mL of water to obtain a 1 M FeCl3 solution.

[0024] Furthermore, the preparation method of the EDOT (25 mg / mL) CHCl3 solution in the fifth step is to weigh 0.25 g of EDOT, add it to 10 mL of CHCl3, and ultrasonically dissolve EDOT completely to prepare 10 mL of EDOT (25 mg / mL) CHCl3 solution.

[0025] A PEDOT-doped MWNTs-loaded Au@BP5 composite optoelectronic material prepared by any of the above preparation methods.

[0026] The present application also discloses an application of a PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material in a novel signal switch type photoelectrochemical PEC sensing system. 2 10 μL of GCE was drop-coated on the glassy carbon electrode

[0027] Au@BP5 / PEDOT-MWNTs composite photoelectric material solution was used to prepare Au@BP5 / PEDOT-MWNTs / GCE nanocomposite electrode.

[0028] Furthermore, the preparation method of the Au@BP5 / PEDOT-MWNTs composite optoelectronic material solution is as follows: 1.7-2.3 mg of the Au@BP5 / PEDOT-MWNTs composite optoelectronic material is dissolved in 2.6-3.2 mL of an aqueous solution according to a mass-to-volume ratio to obtain the Au@BP5 / PEDOT-MWNTs composite optoelectronic material solution.

[0029] Furthermore, the novel signal switch type photoelectrochemical PEC sensing system uses a traditional three-electrode system, with Au@BP5 / PEDOT-MWNTs / GCE nanocomposite electrode as the working electrode, platinum mesh as the counter electrode, and saturated calomel electrode SCE as the reference electrode. A xenon lamp is used to simulate a visible light source to illuminate the surface of Au@BP5 / PEDOT-MWNTs / GCE, and the shading interval time is controlled as an adjustable "on-off". Then, an electrochemical workstation is used for photoelectrochemical detection in HClO solution.

[0030] The principle of the preparation method and application of the above-mentioned Au@BP5 / PEDOT-MWNTs composite optoelectronic material is that the host-guest complexation between BP5 and HClO leads to increased adsorption of HClO on the surface of Au@BP5 / PEDOT-MWNTs / GCE; in addition, Au NPs, as photosensitizers, produce a strong LSPR effect under light, improve the light capture efficiency, so that more light is absorbed, significantly improve the light response efficiency, and further promote the redox of HClO; the introduced MWNTs act as a bridge to accelerate the transmission of electron carriers, and PEDOT contributes to a faster response due to its wider light absorption range, which will achieve highly sensitive and specific photoelectrochemical detection of HClO.

[0031] Beneficial effects:

[0032] The present application provides a PEDOT-doped MWNTs-loaded Au@BP5 composite optoelectronic material and a preparation method and application thereof, which have the following beneficial effects compared with the prior art:

[0033] 1. This application designs gold nanoparticles that form LSPR effect under visible light, BP5 with host-guest complexing ability, and PEDOT-MWNTs composite materials with excellent conductivity for photoelectrochemical detection of HClO;

[0034] 2. Solve technical problems such as low sensitivity, limited detection range, and expensive instruments of the original detection technology;

[0035] 3. The detection range of this application is 0.5μM~340μM, the detection limit is 0.17μM (S / N=3) and the quantification limit is 0.5μM (S / N=3), and the sensitivity is 5.69μAcm -2 μM -1 ;

[0036] 4. The pillar aromatics synthesized in this application have a good host-guest complex constant with HClO, which is 33853;

[0037] 5. The recovery rate of HClO in human serum detected by this application is between 93.30% and 107.76%. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 : are electron microscope images of the present application, wherein A and D are scanning electron microscope images and transmission electron microscope images of PEDOT, B and E are scanning electron microscope images and transmission electron microscope images of PEDOT-MWNTs, C and F are scanning electron microscope images and transmission electron microscope images of Au@BP5 / PEDOT-MWNTs, G is a transmission electron microscope image of Au NPs, H is a high-resolution transmission electron microscope image of Au NPs, and I is a transmission electron microscope image and element distribution image of Au@BP5 / PEDOT-MWNTs;

[0039] Figure 2 It is the XRD powder diffraction pattern, Fourier infrared spectrum and UV-visible absorption spectrum of the present application, wherein A is the XRD powder diffraction pattern of Au, PEDOT, MWNTs and Au@BP5 / PEDOT-MWNTs; B is the Fourier infrared spectrum of MWNTs, PEDOT and Au@BP5 / PEDOT-MWNTs, and C is the UV-visible absorption spectrum, wherein a is MWNTs, b is Au NPs, c is PEDOT, d is BP5, and e is Au@BP5 / PEDOT-MWNTs;

[0040] Figure 3 It is a time current (it) curve and a differential pulse voltammetry diagram in the present application, wherein A is a time current (it) curve of Au@BP5 / GCE, PEDOT / GCE, PEDOT-MWNTs / GCCE and Au@BP5 / PEDOT-MWNTs / GCE modified glassy carbon electrode in 1 mM HClO solution; B is a differential pulse voltammetry (DPV) diagram of Au@BP5 / PEDOT-MWNTs / GCE modified glassy carbon electrode in a solution containing 1 mM HClO with and without light measurement;

[0041] Figure 4 It curve diagram and linear calibration curve diagram of Au@BP5 / PEDOT-MWNTs sensor for different concentrations of HClO in this application, where A is the it curve diagram and B is the linear calibration curve diagram. DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with examples. The examples are only used to illustrate the present invention and do not constitute a limitation on the scope of the claims. Other alternative means that can be thought of by those skilled in the art are all within the scope of the claims of the present invention.

[0043] Embodiment 1:

[0044] A method for preparing a PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material, comprising the steps of: doping poly-3,4-ethylenedioxythiophene on multi-walled carbon nanotubes to prepare PEDOT-MWNTs, and then distributing Au@BP5 on the PEDOT-MWNTs to prepare an Au@BP5 / PEDOT-MWNTs composite photoelectric material.

[0045] The first step is to prepare asymmetric pillar aromatic hydrocarbon BP5:

[0046]

[0047] The second step is to prepare a spherical gold nanoparticle solution: 0.9 mL of 0.1 M citric acid and 2.1 mL of 0.1 M sodium citrate are added to 150 mL of boiling water and stirred at 500 rpm for 15 min; then 1 mL of 25.4 mM chloroauric acid is added and stirred at 500 rpm for 3 min, and then cooled in ice water. The obtained precipitate is washed with ultrapure water and ethanol, and the precipitate is dispersed in 10 mL of ultrapure water to obtain a spherical gold nanoparticle solution;

[0048] The third step is to prepare Au@BP5 by ultrasonic method: 5 mg BP5 was dispersed in 0.5 mL DMF to prepare BP5 solution, and 0.5 mL spherical gold nanoparticle solution prepared in the second step and 0.5 mL BP5 solution were ultrasonically treated for 30 min to prepare Au@BP5. Au@BP5 nanoparticles were synthesized because Au nanoparticles and BP5 have strong thiol-SH bonding with Au.

[0049] The fourth step is to prepare multi-walled carbon nanotubes MWNTs by covalent modification: first, 1 mg of multi-walled carbon nanotubes is dispersed in 50 mL of 68% concentrated nitric acid, ultrasonically treated for 30 min, and then heated and refluxed in an oil bath at 150°C for 5 h, and the obtained product is washed with a large amount of ultrapure water until the pH reaches 7, and then the prepared sample is freeze-dried to obtain oxidized multi-walled carbon nanotubes MWNTs; a MWNTs aqueous dispersion system is prepared by oxidized multi-walled carbon nanotubes MWNTs: deionized water = 0.5 mg: 1 mL according to a mass volume ratio;

[0050] The fifth step is to prepare multi-walled carbon nanotubes doped with poly (3,4-ethylenedioxythiophene) PEDOT-MWNTs: first, add 1 mL of FeCl3 solution to 1 mL of MWNTs aqueous dispersion system (0.5 mg / mL), ultrasonicate for 10 min, then add to 2 mL of EDOT (25 mg / mL) CHCl3 solution, heat at 50°C for 12 h, centrifuge and wash the above mixture, disperse in 10 mL of purified water, and obtain the prepared PEDOT-MWNTs nanohybrid; the FeCl3 solution is prepared by dissolving 1.62 g of FeCl3 in 10 mL of water to obtain a 1 M FeCl3 solution, and the EDOT (25 mg / mL) CHCl3 solution is prepared by weighing 0.25 g of EDOT, adding it to 10 mL of CHCl3, ultrasonicate to completely dissolve EDOT, and obtain 10 mL of EDOT (25 mg / mL) CHCl3 solution;

[0051] In the sixth step, Au@BP5 / PEDOT-MWNTs was synthesized by physical adsorption method: 2mA Au@BP5 prepared in the third step was dropped into 1mg PEDOT-MWNTs nanohybrid prepared in the fifth step, and stirred at 600rpm for 5min to obtain Au@BP5 / PEDOT-MWNTs heterojunction, i.e., Au@BP5 / PEDOT-MWNTs composite optoelectronic material.

[0052] Embodiment 2:

[0053] The surface area is 0.07 cm 2 10 μL of Au@BP5 / PEDOT-MWNTs composite photoelectric material solution was drop-coated on the glassy carbon electrode GCE to prepare Au@BP5 / PEDOT-MWNTs / GCE nanocomposite electrode. The preparation method of the Au@BP5 / PEDOT-MWNTs composite photoelectric material solution was as follows: 1.7 to 2.3 mg of Au@BP5 / PEDOT-MWNTs composite photoelectric material was dissolved in 2.6 to 3.2 mL of aqueous solution according to a mass volume ratio to prepare the Au@BP5 / PEDOT-MWNTs composite photoelectric material solution.

[0054] An Au@BP5 / PEDOT-MWNTs / GCE electrode was placed in HClO solution for photoelectrochemical detection in a novel signal switch-type photoelectrochemical PEC sensor system. The novel signal switch-type photoelectrochemical PEC sensor system uses a traditional three-electrode system, with Au@BP5 / PEDOT-MWNTs / GCE electrode as the working electrode, platinum mesh as the counter electrode, and saturated calomel electrode SCE as the reference electrode. Photoelectrochemical detection was performed using an electrochemical workstation, and a xenon lamp was used as a simulated power source.

[0055] Performance Testing

[0056] 1. Morphology determination of PEDOT, PEDOT-MWNTs, AuNPs and Au@BP5 / PEDOT-MWNTs

[0057] like Figure 1 As shown in A and D, A and D are scanning electron microscope images and transmission electron microscope images of PEDOT, showing a thin-sheet structure and layer stacking. Figure 1 It can be seen from B and F that after modification with MWNTs, the PEDOT nanosheets fill the gaps between the MWNTs tubes, forming a PEDOT-MWNTs nanohybrid with a larger surface area. Figure 1 C and F depict the S images of Au@BP5 / PEDOT-MWNTs, where the tubular network serves as the supporting substrate and the gold nanoparticles (about 15 nm in size) ( Figure 1 G) are randomly distributed on the substrate to form the final composite material. Figure 1 Figure 1 shows the transmission electron microscopy and elemental analysis images of Au@BP5 / PEDOT-MWNTs nanohybrids. There are a large amount of C and O on the surface of the composite material, as well as a small amount of S and Au. This confirms the successful preparation of the composite material.

[0058] 2. XRD powder diffraction pattern, Fourier transform infrared spectrum and UV-visible absorption spectrum of Au@BP5 / PEDOT-MWNTs composite photoelectric material

[0059] Figure 2 Figure A is the XRD powder diffraction pattern of Au, PEDOT, MWNTs and Au@BP5 / PEDOT-MWNTs. It can be seen from the figure that the characteristic diffraction peaks of MWNTs appear at 25.8° and 43.2°, corresponding to the (002) and (100) crystal planes, respectively. PEDOT has a significant characteristic peak at 2θ of 25.3°, which can be attributed to the (020) plane, indicating the inter-chain planar ring stacking. The Au@BP5 / PEDOT-MWNTs nanocomposite has four characteristic diffraction peaks at 37.9°, 43.8°, 64.2° and 77.1°, representing the (111), (200), (220) and (311) crystal planes of Au, respectively, indicating the successful synthesis of Au@BP5 / PEDOT-MWNTs composite optoelectronic materials.

[0060] Figure 2 Figure B is the Fourier infrared image of MWNTs, PEDOT and Au@BP5 / PEDOT-MWNTs. The main characteristic band of PEDOT in the composite spectrum is: 684cm -1 、839cm -1 and 977cm -1 The band at 1087cm corresponds to the stretching vibration of CSC and CS bonds in the thiophene ring;-1 The nearby band is associated with the bending vibration of COC in vinyl dioxygen, 1318 cm -1 and 1519cm -1 The nearby bands represent C=C asymmetric stretching and CC staggered stretching. These characteristic bands verify the successful synthesis of polymer PEDOT. The spectrum of PEDOT is compared with that of MWNTs, and it is found that the two are highly similar. These characteristic bands are also retained in the Au@BP5 / PEDOT-MWNTs composite material, among which the peaks at 1600cm -1 、1460cm -1 and 1400cm -1 Several absorption peaks at 2920 cm-1 are attributed to the stretching vibration of the benzene ring region on BP5. -1 and 2850cm -1 The stretching vibration at is attributed to CH2.

[0061] Figure 2 C is the UV-visible absorption spectra of MWNTs, AuNPs, PEDOT, BP5 and Au@BP5 / PEDOT-MWNTs. The UV absorption peak of MWNTs has a peak at 260nm that is similar to the carbon atom sp 2 Hybridization-related absorption peaks. AuNPs show a typical absorption peak of the surface plasmon resonance band at 525nm. PEDOT has a broad absorption peak at 470-520nm, while the absorption peak at 300nm corresponds to the absorption peak of BP5. For Au@BP5 / PEDOT-MWNTs (curve e), two absorption peaks are clearly observed at 260nm and 470-520nm, indicating that Au@BP5 and PEDOT-MWNTs are successfully prepared.

[0062] 3. Photoelectrochemical Characterization

[0063] like Figure 3As shown in Figure A, the photoelectrochemical activities of Au@BP5 / GCE, PEDOT / GCE, PEDOT-MWNTs / GCCE and Au@BP5 / PEDOT-MWNTs / GCE were investigated by time-current curves (it) in a solution containing 1 mM HClO. Under illumination, the photocurrent density increased significantly, indicating that the photoelectrochemical performance of the composite material was enhanced. In sharp contrast, under dark conditions, the photocurrent density dropped rapidly, highlighting the dependence of the photoactivity on light. Compared with Au@BP5 / GCE and PEDOT / GCE alone, PEDOT-MWNTs / GCE exhibited the most stable photocurrent density, demonstrating its superior photoelectrochemical capability. This phenomenon can also be clearly observed from the differential pulse curves obtained by DPV analysis of Au@BP5 / PEDOT-MWNTs / GCE. In a PBS solution containing 1 mM HClO, the analysis was performed under visible light irradiation and in the absence of light, as shown in Figure 1. Figure 3 As shown in B. Under visible light irradiation, the oxidation peak current of Au@BP5 / PEDOT-MWNTs / GCE is about 43.21μA / cm 2 , compared with the peak current of oxidation under no light irradiation (about 35.69μA / cm 2 )High 7.52μA / cm 2 .

[0064] 4. Detection of HClO

[0065] like Figure 4 As shown in the figure, as the HCIO concentration increases, the photocurrent density also increases. There is a strong linear correlation in the concentration range of 0.5μM to 10μM, and the linear equation is I = 5.6852C HClO -79.7625(R 2 =0.9957). In the range of 10 μM to 340 μM, the equation is I = 0.0724C HClO -22.2950(R 2 =0.9918). The calculated detection limit was 0.17 μM.

[0066] Example 3

[0067] A method for preparing a composite photoelectric material of Au@BP5-modified multi-walled carbon nanotubes and flower-shaped bismuth oxybromide, wherein PEDOT-MWNTs are prepared by doping multi-walled carbon nanotubes with poly (3,4-ethylenedioxythiophene), and then Au@BP5 is distributed on the PEDOT-MWNTs to prepare the Au@BP5 / PEDOT-MWNTs composite photoelectric material, which specifically comprises the following steps:

[0068] The first step is to prepare asymmetric pillar aromatic hydrocarbon BP5:

[0069]

[0070] The second step is to prepare Au nanoparticles: 1.2 mL of 0.1 M citric acid and 2.8 mL of 0.1 M sodium citrate are added to 200 mL of boiling water, and stirred at 700 rpm for 20 min; 1.3 mL of 25.4 mM chloroauric acid is added, and stirred at 700 rpm for 5 min, and then cooled in ice water, and the precipitate obtained above is washed with ultrapure water and ethanol, and the precipitate is dispersed in 10 mL of ultrapure water to obtain a spherical gold nanoparticle solution;

[0071] The third step is to prepare Au@BP5 by ultrasonic method: 5.5 mg BP5 was dispersed in 1 mL DMF to prepare BP5 solution, and 1 mL of the gold nanoparticle solution prepared in the second step and 1 mL of BP5 solution were ultrasonically treated for 30 min to prepare Au@BP5. Au@BP5 nanoparticles were synthesized because Au nanoparticles and BP5 have strong thiol-SH bonding with Au.

[0072] The fourth step is to prepare multi-walled carbon nanotubes MWNTs by covalent modification: first, 1.5 mg of multi-walled carbon nanotubes are dispersed in 50 mL of 68% concentrated nitric acid, ultrasonically treated for 35 min, and then heated and refluxed in an oil bath at 160°C for 5 h, and the obtained product is washed with a large amount of ultrapure water until the pH reaches 7, and then the prepared sample is freeze-dried to obtain oxidized multi-walled carbon nanotubes MWNTs, and a MWNTs aqueous dispersion system is prepared by oxidized multi-walled carbon nanotubes MWNTs: deionized water = 0.5 mg: 1 mL according to a mass volume ratio;

[0073] The fifth step is to prepare multi-walled carbon nanotubes doped with poly (3,4-ethylenedioxythiophene) PEDOT-MWNTs: first, add 2 mL of FeCl3 solution to 2 mL of MWNTs aqueous dispersion system (0.5 mg / mL), ultrasonicate for 15 min, then add to 4 mL of EDOT (25 mg / mL) CHCl3 solution, heat at 60°C for 13 h, centrifuge and wash the above mixture, disperse in 12 mL of purified water, and obtain the prepared PEDOT-MWNTs nanohybrid. The FeCl3 solution is prepared by dissolving 1.62 g of FeCl3 in 10 mL of water to obtain a 1 M FeCl3 solution. The EDOT (25 mg / mL) CHCl3 solution is prepared by weighing 0.25 g of EDOT, adding it to 10 mL of CHCl3, ultrasonicate to completely dissolve EDOT, and obtain 10 mL of EDOT (25 mg / mL) CHCl3 solution.

[0074] In the sixth step, Au@BP5 / PEDOT-MWNTs was synthesized by physical adsorption method: 2.5 mL of Au@BP5 prepared in the third step was dropped into 1.5 mg of PEDOT-MWNTs nanohybrid prepared in the fifth step, and stirred at 800 rpm for 10 min to obtain Au@BP5 / PEDOT-MWNTs heterojunction, i.e., Au@BP5 / PEDOT-MWNTs composite optoelectronic material.

[0075] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for preparing a PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material, characterized in that: The Au@BP5 / PEDOT-MWNTs composite photoelectric material is prepared by doping poly (3,4-ethylenedioxythiophene) on multi-walled carbon nanotubes, and then distributing Au@BP5 on the PEDOT-MWNTs, which specifically includes the following steps: The first step is to prepare asymmetric pillar aromatic hydrocarbon BP5: The second step is to prepare a spherical gold nanoparticle solution: using chloroauric acid as a raw material, citric acid and sodium citrate as reducing agents, and using a thermal reduction method to prepare a spherical gold nanoparticle solution, wherein the amount ratio of the chloroauric acid, citric acid and sodium citrate is 1-1.3 mL of 25.4 mM chloroauric acid: 0.9-1.2 mL of 0.1 M citric acid: 2.1-2.8 mL of 0.1 M sodium citrate; The third step is to prepare Au@BP5 by ultrasonic method: 5-5.5 mg BP5 is dispersed in 0.5-1 mL DMF to prepare BP5 solution according to mass volume ratio, 0.5-1 mL spherical gold nanoparticle solution is added to the BP5 solution, and Au@BP5 is prepared by ultrasonication for 30-35 min; The fourth step is to prepare multi-walled carbon nanotubes MWNTs by covalent modification: first, 1-1.5 mg of multi-walled carbon nanotubes are dispersed in 50 mL of 68% concentrated nitric acid according to a mass volume ratio, and ultrasonic treatment is performed for 30-35 min, and then heated and refluxed in an oil bath at 150-160° C. for 5-6 h, and the obtained product is washed with ultrapure water until the pH reaches 7, and finally freeze-dried to obtain oxidized multi-walled carbon nanotubes MWNTs, and a MWNTs water dispersion system is prepared by oxidized multi-walled carbon nanotubes MWNTs: deionized water = 0.5 mg: 1 mL according to a mass volume ratio; The fifth step is to prepare multi-walled carbon nanotubes doped with poly (3,4-ethylenedioxythiophene) PEDOT-MWNTs: first, add 1-2 mL of FeCl3 solution to 1-2 mL of MWNTs aqueous dispersion system by volume, ultrasonicate for 10-15 min, then add 2-4 mL of EDOT (25 mg / mL) CHCl3 solution, heat at 50-60°C for 12-13 h, centrifuge and wash the mixture, disperse it in 10-12 mL of purified water, and prepare PEDOT-MWNTs nanohybrids; In the sixth step, Au@BP5 / PEDOT-MWNTs was synthesized by physical adsorption method: 2-2.5 mL Au@BP5 was dropped into 1-1.5 mg PEDOT-MWNTs nanohybrid according to the mass-to-volume ratio, and stirred at 600-800 rpm for 5-10 min to obtain Au@BP5 / PEDOT-MWNTs heterojunction, i.e., Au@BP5 / PEDOT-MWNTs composite optoelectronic material.

2. The method for preparing a PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material according to claim 1, characterized in that: The second step of the thermal reduction method to prepare the spherical gold nanoparticle solution is specifically as follows: 0.9-1.2 mL of 0.1 M citric acid: 2.1-2.8 mL of 0.1 M sodium citrate are added to 150-200 mL of boiling water, and stirred at 500-700 rpm for 15-20 min; then 1-1.3 mL of 25.4 mM chloroauric acid is added, and the mixture is stirred at 500-700 rpm for 3-5 min, and then cooled in ice water. The obtained precipitate is washed with ultrapure water and ethanol, and the washed precipitate is dispersed in the ultrapure water solution to prepare the spherical gold nanoparticle solution.

3. The method for preparing a PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material according to claim 1, characterized in that: The method for preparing the FeCl3 solution in the fifth step is to dissolve 1.62 g of FeCl3 in 10 mL of water to obtain a 1 M FeCl3 solution.

4. The method for preparing a PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material according to claim 1, characterized in that: The preparation method of the EDOT (25 mg / mL) CHCl3 solution in the fifth step is to weigh 0.25 g of EDOT, add it to 10 mL of CHCl3, and ultrasonically dissolve EDOT completely to prepare 10 mL of EDOT (25 mg / mL) CHCl3 solution.

5. A PEDOT-doped MWNTs-loaded Au@BP5 composite photoelectric material prepared by the preparation method according to any one of claims 1 to 4.

6. An application of the PEDOT-doped MWNTs loaded with Au@BP5 composite photoelectric material according to claim 5 in a novel signal switch type photoelectrochemical PEC sensing system, characterized in that: The surface area is 0.07 cm 2 10 μL of Au@BP5 / PEDOT-MWNTs composite photoelectric material solution was drop-coated on the glassy carbon electrode GCE to prepare Au@BP5 / PEDOT-MWNTs / GCE nanocomposite electrode.

7. The use of the PEDOT-doped MWNTs loaded with Au@BP5 composite photoelectric material in a novel signal switch type photoelectrochemical PEC sensing system according to claim 6, characterized in that: The preparation method of Au@BP5 / PEDOT-MWNTs composite photoelectric material solution is as follows: 1.7-2.3 mg of Au@BP5 / PEDOT-MWNTs composite photoelectric material is dissolved in 2.6-3.2 mL of aqueous solution according to a mass volume ratio to obtain the Au@BP5 / PEDOT-MWNTs composite photoelectric material solution.

8. The use of the PEDOT-doped MWNTs loaded with Au@BP5 composite photoelectric material in a novel signal switch type photoelectrochemical PEC sensing system according to claim 6, characterized in that: The novel signal switch type photoelectrochemical PEC sensing system uses the traditional three-electrode system, with Au@BP5 / PEDOT-MWNTs / GCE nanocomposite electrode as the working electrode, platinum mesh as the counter electrode, and saturated calomel electrode SCE as the reference electrode. A xenon lamp is used to simulate a visible light source to illuminate the surface of Au@BP5 / PEDOT-MWNTs / GCE, and the shading interval time is controlled as an adjustable "on-off". Then, an electrochemical workstation is used for photoelectrochemical detection in HClO solution.

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