CN113514106A - Preparation method and application of multifunctional sensor for synchronously measuring temperature, pressure and humidity - Google Patents
Preparation method and application of multifunctional sensor for synchronously measuring temperature, pressure and humidity Download PDFInfo
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Abstract
The invention discloses a preparation method and application of a multifunctional sensor for synchronously measuring temperature, pressure and humidity. Firstly, preparing a regular dual-through-hole anodic alumina template by adopting a step depressurization method, then polymerizing monomer pyrrole onto the pore walls of the dual-through-hole anodic alumina by adopting a chemical in-situ polymerization method by taking the dual-through-hole anodic alumina as the template, spin-coating a polyurethane solution onto the dual-through-hole anodic alumina plated with the polypyrrole, placing the template into a phosphoric acid aqueous solution to dissolve the dual-through-hole anodic alumina, thus obtaining a highly regular porous flexible conductive film, and packaging the conductive film and a fabric single-side electrode to obtain the multifunctional sensor for synchronously measuring temperature, pressure and humidity. The method has simple process and low cost, the prepared film has the conductivity of polypyrrole and the flexibility of flexible high polymer, the prepared sensor has small size and good sensing performance on pressure, temperature and humidity, and the coupling effect and the mutual crosstalk phenomenon do not exist among the three.
Description
Technical Field
The invention belongs to the technical field of electrochemistry, and particularly relates to a preparation method and application of a multifunctional sensor for synchronously measuring temperature, pressure and humidity.
Background
In view of the multifunctional perception capability of the bionic skin, the electronic skin has great application potential in human-computer interfaces, intelligent artificial limbs and health monitoring. As one of the core components of electronic skin, a flexible pressure sensor can convert external stimuli into various electronic signals, and has significant advantages such as high sensitivity, multifunction, wearability and portability, and air and moisture permeability to skin, ensuring high applicability, reliability and comfort. However, integrating these functions into the same sensor remains a challenge.
Researchers have recently attempted to develop multi-functional sensors, i.e., coupling two functions to one sensor that can detect multiple stimuli. Zhang et al (Zhang F, Zang Y, Nature Communications,2015,6:8356) demonstrate a temperature-pressure two-parameter sensor utilizing an organic thermoelectric material supported by a microstructure framework. A pressure and temperature two-parameter sensor is prepared from a composite film Of an organic piezoelectric poly (vinylidene fluoride) and a pyroelectric Polyaniline (PANI) based sandwich structure designed by Zhu et al (Zhu P, Journal Of Materials Chemistry A,2019,7(14): 8258-8267).
The current common multifunctional sensor can sense two physical signals simultaneously. The integration method is usually manufactured by integrating a plurality of single-function sensors into a sensing array, and can output signals simultaneously without signal interference, but has the disadvantages of large size, complex structure and process and high cost of the array sensor. The other method is to directly compound a plurality of materials with different sensing characteristics or to prepare a single device by utilizing the sensitive characteristics of multiple physical quantities of the materials, and the method has the advantages of simple structure and easy preparation, but has the greatest limitation that obvious coupling effect exists among physical signals and crosstalk occurs among the physical signals.
Disclosure of Invention
The invention aims to provide a preparation method of a multifunctional sensor for synchronously measuring temperature, pressure and humidity, which has the advantages of small size, simple structure and process, low cost and no interference among signals.
The invention also aims to provide application of the sensor prepared by the preparation method.
Therefore, the invention adopts the following technical scheme:
a method for preparing a multifunctional sensor for synchronously measuring temperature, pressure and humidity comprises the following steps:
(1) pretreating the surface of the high-purity aluminum, taking the pretreated high-purity aluminum sheet as an anode and a titanium plate as a cathode, and performing electrochemical polishing in a mixed solution of perchloric acid and absolute ethyl alcohol to obtain an aluminum sheet with a smooth surface;
(2) carrying out primary oxidation in a mixed solution of phosphoric acid and oxalic acid by taking the aluminum sheet obtained in the step (1) as an anode and a titanium plate as a cathode; placing the aluminum oxide film with the aluminum substrate after primary oxidation in a mixed solution of chromium trioxide and phosphoric acid to remove generated aluminum oxide, and obtaining an aluminum sheet with regular pits on the surface;
(3) taking the aluminum sheet obtained in the step (2) as an anode, performing step-pressure reduction anodic oxidation under the condition that the condition is the same as that of primary oxidation, and after the oxidation is finished, performing chemical corrosion in a phosphoric acid solution to form a through hole anodic aluminum oxide template on the surface of the aluminum sheet;
(4) polymerizing pyrrole monomers onto the hole wall of the through hole anodic aluminum oxide template obtained in the step (3) by adopting a chemical in-situ polymerization method;
(5) spin-coating a flexible high polymer solution on the through-hole alumina template with the polypyrrole attached on the surface obtained in the step (4) by using a spin-coating method, and placing the template in a vacuum drying oven for high-temperature treatment under a vacuum condition, wherein the flexible high polymer is polymethyl methacrylate, polystyrene, polyurethane or polyacrylonitrile;
(6) placing the through hole anodized aluminum template with the aluminum sheet treated in the step (5) in a mixed solution of hydrochloric acid and copper chloride, and removing the aluminum sheet;
(7) placing the through hole anodic alumina template with polypyrrole and flexible high polymer attached on the surface in a phosphoric acid aqueous solution to remove the through hole anodic alumina template, and obtaining a regular porous flexible conductive film;
(8) and (4) packaging the fabric, the regular porous flexible conductive film obtained in the step (7), the fabric interdigital electrode and the superfine lead to obtain the multifunctional sensor for synchronously measuring the temperature, the pressure and the humidity.
In the step (1), the purity of the high-purity aluminum sheet is higher than 99%, and the pretreatment comprises the following steps: ultrasonic cleaning in acetone for 5-15min, drying, and placing in 1mol/L NaOH solution for 10-20min to remove natural oxide layer on the surface; the mixed solution of perchloric acid and absolute ethyl alcohol is formed by mixing perchloric acid and absolute ethyl alcohol in a volume ratio of 1 (3.5-4.5), the voltage is 20-25V, the polishing time is 4-6min, and the temperature is 0-5 ℃.
In the step (2), during the primary oxidation, the concentration of oxalic acid in the mixed solution is 0.01-0.03M and the concentration of diluted phosphoric acid is 0.5-2 wt%, the oxidation voltage is 190-5V, the temperature is 0-5 ℃, and the oxidation time is 3-5 h; the mixed water solution of chromium trioxide and phosphoric acid for removing oxide film contains 12-20g/L CrO3And 4-10 wt% of H3PO4The temperature is 50-80 ℃.
In the step (3), the initial voltage range of the oxidation voltage is 190-210V, the pressure reduction rate is 1-3V/min, the target voltage range of the pressure reduction is 0-70V, the concentration of the phosphoric acid solution is 3-10 wt%, the corrosion time is 3-4h, and the temperature is 25-45 ℃.
In the step (4), the conical anodic alumina template is immersed into pyrrole aqueous solution with the concentration of 0.03-0.07M and magnetically stirred for 20-40min, then mixed aqueous solution containing 0.05-0.12M of p-toluenesulfonic acid and 0.05-0.10M of ferric trichloride with the same volume is added, the polymerization time is 40-80min, and the process is also carried out under the condition of magnetic stirring; the thickness of polypyrrole on the through hole anodic alumina template is 10nm-5 μm.
In the step (5), the solvent of the solution of the flexible high polymer is N, N-dimethylformamide, the mass fraction of the solute is 10-25 wt%, the rotation speed of a spin coater is 500-4000/min, the spin coating time is 10-30s, the temperature of a vacuum drying oven is 80-160 ℃, and the time is 1.5-3.5 h; the thickness of the flexible high polymer coating is 100nm-100 mu m.
In the step (6), the concentration of hydrochloric acid is 5-25 wt% and the concentration of copper chloride is 0.05-0.15mol/L in the mixed solution of hydrochloric acid and copper chloride.
In the step (7), the mass fraction of the phosphoric acid aqueous solution is 10-30 wt%, the reaction temperature is 20-60 ℃, and the aperture of the regular porous flexible conductive film is 50-1000 nm.
In the step (8), the fabric of the fabric electrode is woven fabric, knitted fabric, non-woven fabric or a flexible high polymer film, the preparation method of the fabric electrode is to coat conductive copper, gold, platinum or titanium slurry on the fabric by adopting screen printing, or coat copper, platinum, titanium or a composite coating electrode thereof on the fabric by adopting magnetron sputtering method, the distance between the electrodes is 0.1-5mm, and the packaging method of the sensor is to paste flexible fabric adhesive tape or to bond the flexible conductive high polymer film and the fabric electrode together by adopting a hot pressing method.
The method for synchronously measuring the temperature, the pressure and the humidity by using the multifunctional sensor prepared by the method comprises the following steps:
(1) testing the electrochemical impedance spectrum of the multifunctional sensor under the conditions of different pressures, different temperatures and different humidities;
(2) constructing an equivalent circuit model for measuring the electrochemical impedance spectrum;
(3) fitting parameters of the equivalent circuit model by using the electrochemical impedance spectrum in the step (1) and the equivalent circuit model in the step (2) and combining electrochemical software;
(4) constructing a functional relation model of the equivalent circuit model parameters in the step (3) and corresponding pressure, temperature and humidity values;
(5) and (3) under certain pressure, temperature and humidity conditions, measuring the electrochemical impedance spectrum of the multifunctional sensor, fitting parameters of an equivalent circuit model corresponding to the electrochemical impedance spectrum, and calculating pressure, temperature and humidity data under the conditions by applying the functional relation model in the step (4).
The method takes the through-hole anodic alumina as a template, adopts the in-situ polymerization pyrrole and high polymer spin coating method, and dissolves the through-hole anodic alumina in the phosphoric acid aqueous solution to prepare the regular porous flexible conductive film, and the film has the conductivity of the polypyrrole and the flexibility of polyurethane. The film is then packaged with a fabric single-sided electrode to obtain a sensor capable of detecting temperature, pressure and humidity.
The invention has the following beneficial effects:
(1) the method which adopts the through-hole anodic aluminum oxide as the template and adopts the in-situ polymerized pyrrole monomer and the spin-coating polyurethane in situ has the advantages of easily obtained raw materials, simple process and no need of large-scale equipment, thereby having low cost;
(2) the method of step depressurization and prolonging of chemical corrosion time is adopted to ensure the through holes of the anodic aluminum oxide template and greatly enlarge the aperture of the anodic aluminum oxide template while ensuring the structural integrity; the porous flexible conductive high polymer film prepared by the large-aperture anodic alumina template has regular structure and large specific surface area, and is beneficial to realizing the high sensitivity of the sensor in the aspect of pressure;
(3) the regular porous flexible conductive film prepared by the method has a regular porous structure, and good elastic recovery performance of polyurethane and sensitivity characteristics of polypyrrole to temperature and humidity, so that the regular porous flexible conductive film can be used for preparing a multifunctional sensor;
(4) the invention adopts the regular porous flexible conductive film with sensitive characteristics on pressure, temperature and humidity to prepare a single device, the complex process of integrating a plurality of sensors does not exist, and the size of the porous flexible conductive high polymer film is only 1cm by 1cm, so that the invention has the advantages of small size, simple structure and easy carrying;
(5) according to the multifunctional sensor for synchronously measuring the temperature, the pressure and the humidity, the flexibility, the air permeability and the moisture permeability of the multifunctional sensor are ensured by combining the regular porous flexible conductive film with the single-side electrode of the fabric;
(6) the multifunctional sensor for synchronously measuring the temperature, the pressure and the humidity, which is prepared by the invention, has good sensing performance on the pressure, the temperature and the humidity, and the coupling effect and the mutual crosstalk phenomenon do not exist among the three.
Drawings
Fig. 1(a) -1 (c) are FESEM images of the structured porous flexible conductive film prepared in example 1, wherein: FIG. (a) is a front view, FIG. (b) is a rear view, and FIG. (c) is a longitudinal sectional view;
FIG. 2 is a DSC thermogram of the structured porous flexible conductive film prepared in example 1;
FIG. 3 is a schematic of the packaging of the multifunction sensor of the present invention;
FIG. 4 is a schematic structural view of a structured porous flexible conductive film of the present invention;
FIGS. 5(a) - (c) are graphs of the rate of change of resistance of pressure, temperature, humidity, respectively, for a multifunctional sensor made using the conductive film prepared in example 1;
FIG. 6a is an electrochemical impedance diagram of a multifunctional sensor for simultaneous measurement of temperature, pressure and humidity, prepared by using the conductive film prepared in example 1, under different pressures;
FIG. 6b is a graph of electrochemical phase angle at different pressures for a multifunctional sensor prepared using the conductive film prepared in example 1 to simultaneously measure temperature, pressure and humidity;
FIG. 6c is an electrochemical impedance diagram of a multifunctional sensor prepared by using the conductive film prepared in example 1 for simultaneously measuring temperature, pressure and humidity at different temperatures;
FIG. 6d is a graph of electrochemical phase angle at different temperatures for a multifunctional sensor prepared using the conductive film prepared in example 1 to simultaneously measure temperature, pressure and humidity;
FIG. 6e is an electrochemical impedance diagram of a multifunctional sensor for simultaneous measurement of temperature, pressure and humidity prepared by using the conductive film prepared in example 1 under different humidity;
fig. 6f is an electrochemical phase angle diagram of a multifunctional sensor for synchronously measuring temperature, pressure and humidity, which is prepared by using the conductive film prepared in example 1, under different humidities.
Fig. 7 is an equivalent circuit diagram of the electrochemical impedance spectroscopy test of fig. 6.
In the figure:
1. fabric 2, regular porous flexible conductive film 3, interdigital electrode 4 and superfine wire
21. Polypyrrole layer 22, flexible high polymer layer 23 and cavity
Detailed Description
The process of the present invention will be described in detail with reference to specific examples.
Example 1
A method for preparing a regular porous flexible conductive film comprises the following steps:
(1) ultrasonically cleaning a high-purity aluminum sheet with the purity of 99.999% in acetone for 15min to remove grease on the surface, then cleaning the aluminum sheet with deionized water, then placing the aluminum sheet in a 1mol/L NaOH solution for 10min to remove a natural oxidation layer on the surface, and finally cleaning and drying the aluminum sheet with deionized water; taking a pretreated aluminum sheet as an anode and a titanium sheet as a cathode, and performing electrochemical polishing for 5min in a mixed solution of perchloric acid and absolute ethyl alcohol with a volume ratio of 1:4 at a voltage of 21V and a temperature of 0-5 ℃ to obtain an aluminum sheet with a smooth surface;
(2) taking the polished aluminum sheet as an anode, taking a titanium plate as a cathode, and taking a mixed solution containing 0.03M oxalic acid and 1 wt% of phosphoric acid (namely, the concentrations of the oxalic acid and the phosphoric acid in the mixed solution are respectively 0.03M and 1 wt%, the same applies below) as an electrolyte for primary oxidation, wherein the oxidation voltage is 200V, the temperature is 0-3 ℃, and the oxidation time is 4 hours; placing the primary oxidized aluminum oxide film with the aluminum substrate in a CrO containing 18g/L3And 6 wt% of H3PO4Removing the generated alumina at 60 ℃ in the mixed solution to obtain an aluminum sheet with regular pits on the surface;
(3) performing step-down oxidation again under the same condition as the primary oxidation, namely reducing the oxidation voltage from 200V to 0V at the speed of 2V/min, and performing chemical corrosion by using 5 wt% phosphoric acid solution for 4h at the temperature of 30 ℃ to obtain a through hole Anodized Aluminum (AAO) template;
(4) soaking the prepared through-hole anodized aluminum template in pyrrole (Py) aqueous solution with the volume of 10ml and the concentration of 0.05M, and magnetically stirring for 30min to ensure that the Py aqueous solution can fully enter holes of the AAO template; then 10ml of mixed aqueous solution containing 0.08M of dopant p-toluenesulfonic acid and 0.07M of oxidant ferric trichloride is added for polymerization for 60min, and the process is also carried out under the condition of magnetic stirring;
(5) dripping 15 wt% of polyurethane solution on a through hole anodic alumina template with polypyrrole, wherein the rotating speed of a spin coater is 800/min, the spin coating time is 30s, placing the template in a vacuum drying oven after spin coating, performing high-temperature treatment in a vacuum state, setting the temperature at 80 ℃, keeping the temperature for 2h, and then naturally cooling to room temperature;
(6) placing the through hole anodized aluminum template with the aluminum sheet treated in the step (5) in a mixed solution containing 10% hydrochloric acid and 0.1mol/L copper chloride, and removing the aluminum sheet;
(7) then, reacting the through hole anodized aluminum template in a phosphoric acid solution with the temperature of 30 ℃ and the weight of 20 w% to obtain a regular porous flexible conductive film, wherein the structure of the regular porous flexible conductive film is shown in fig. 4, a polypyrrole layer 21 is formed on the top surface of the original through hole Anodized Aluminum (AAO) template and the inner wall of the through hole, and a flexible high polymer layer 22 (polyurethane layer) is coated outside the polypyrrole layer 21; a cavity 23 is formed where the through hole anodized aluminum template was originally located.
The FESEM picture of the regular porous flexible conductive film is shown in figure 1. As can be seen from the figure, the conductive film structure presents a tubular porous structure which is double-pass up and down, the structure is highly ordered and has a large specific surface area, the aperture of the front side is 316.4nm, the aperture of the back side is 281.1nm, the height is 8.57 mu m, and the structure is in the micro-nano level, and the through hole tubular structure is beneficial to the realization of the air permeability and moisture permeability of the prepared multifunctional sensor in the humidity sensing application; the micro-nano structure and the large specific surface area are beneficial to the prepared multifunctional sensor to have high-sensitivity performance in the aspect of pressure.
Example 2
A method for preparing a regular porous flexible conductive film is the same as that in example 1 except that the polymer solution in step (5) is changed to a 20 wt% polymethyl methacrylate solution, and the temperature of an oven is set to 150 ℃.
The structural size of the obtained regular porous flexible conductive film is the same as that of the embodiment 1, and the multifunctional sensor prepared by the conductive film has the performance of being sensitive to pressure, temperature and humidity.
Example 3
A method for preparing a regular porous flexible conductive film is the same as that in example 1 except that the high polymer solution in step (5) is changed into a 25 wt% polystyrene solution, and the temperature of an oven is set to 120 ℃.
The structural size of the regular porous flexible conductive film is the same as that of the embodiment 1, and the multifunctional sensor prepared by the conductive film has the performance of being sensitive to pressure, temperature and humidity.
Example 4
The preparation method of the regular porous flexible conductive film is the same as that in the example 1 except that the polymer solution in the step (3) is changed into 15 wt% polyacrylonitrile solution, and the temperature of an oven is set to be 160 ℃.
The structural size of the obtained regular porous flexible conductive film is the same as that of the embodiment 1, and the multifunctional sensor prepared by the conductive film has the performance of being sensitive to pressure, temperature and humidity.
DSC thermal analysis of porous flexible conductive polymer film
The DSC thermogram of the regular porous flexible conductive film prepared in example 1 is shown in FIG. 2, and the glass transition temperature of the nanoporous PPy @ PU conductive film is 99.3 ℃. This shows that the multifunctional sensor prepared by the conductive film does not damage the porous structure of the film when the temperature sensing performance measurement is carried out at the temperature of less than 99.3 ℃, and can ensure that the sensing performance of the multifunctional sensor is effective in the range of 20-90 ℃.
EXAMPLE 5 preparation of the sensor
Referring to fig. 3, firstly, a screen printing method is adopted to coat conductive silver paste on the fabric, and the fabric is dried in an oven at 80 ℃ for 1 hour to obtain the fabric interdigital electrode 3, wherein the conductive silver paste is semi-dry; and bonding the superfine conducting wires 4 to the fabric interdigital electrodes 3. And then carrying out hot-pressing adhesion on the regular porous flexible conductive film 2, the fabric interdigital electrode 3 and the fabric 1 by adopting a hot-pressing method to obtain the flexible sensor sensitive to pressure, temperature and humidity.
Sensitivity analysis of sensors made from structured porous Flexible conductive films prepared in example 1
Referring to FIGS. 5a-5c, it can be seen that the multiple functionsThe sensor has sensitive characteristics to pressure, temperature and humidity, and in the aspect of pressure, a formula is calculated according to pressure sensitivity
(wherein, SpFor pressure sensitivity, P is pressure) the pressure sensitivity of the sensor at 0-200Pa is calculated to be 102.99kPa-1A value substantially greater than the sensitivity value of existing pressure sensors;
in terms of temperature, the formula is calculated according to the temperature sensitivity
(wherein, STPressure sensitivity, T is temperature) is calculated to be 0.5687 percent in the temperature range of 20-90 DEG C-1；
In terms of humidity, according to the temperature sensitivity calculation formula:
(wherein, SHFor pressure sensitivity, H is humidity) was calculated to be 0.096% RH when the humidity was 40 RH%-1When the humidity was 80 RH%, the humidity sensitivity was increased to 0.371% RH-1. The temperature and humidity sensitivity values are comparable to those reported in the prior art.
Example 6
The method for synchronously measuring the temperature, the pressure and the humidity by using the multifunctional sensor prepared by the method comprises the following steps:
(1) testing the electrochemical impedance spectrum of the multifunctional sensor under the conditions of different pressures, different temperatures and different humidities;
(2) constructing an equivalent circuit model for measuring the electrochemical impedance spectrum;
(3) fitting parameters of the equivalent circuit model by using the electrochemical impedance spectrum in the step (1) and the equivalent circuit model in the step (2) and combining electrochemical software;
(4) constructing a functional relation model of the equivalent circuit model parameters in the step (3) and corresponding pressure, temperature and humidity values;
(5) and (3) under certain pressure, temperature and humidity conditions, measuring the electrochemical impedance spectrum of the multifunctional sensor, fitting parameters of an equivalent circuit model corresponding to the electrochemical impedance spectrum, and calculating pressure, temperature and humidity data under the conditions by applying the functional relation model in the step (4).
An electrochemical impedance spectrogram and an electrochemical phase angle diagram obtained when the multifunctional sensor of the structured porous flexible conductive film prepared in the embodiment 1 is adopted in the flexible sensor are shown in fig. 6a-f, and a test equivalent circuit of the flexible sensor is shown in fig. 7.
Referring to fig. 6a, it is shown that the greater the pressure, the smaller the electrochemical impedance value of the multifunctional sensor.
Figure 6b shows that the multifunctional sensor has a phase angle of almost 0 deg. below 1kHz at different loading pressures, showing resistive behavior, mainly because the distance between the capacitors is smaller with increasing pressure, resulting in a decrease in the overall impedance.
Figure 6c shows that as the temperature increases, the impedance of the multifunction sensor also decreases.
Fig. 6d shows that at different temperatures, along with the decrease of the frequency, the phase angle of the multifunctional sensor gradually decreases to 0 °, that is, the capacitance behavior gradually changes to the resistance behavior, and along with the increase of the temperature, the phase angle of the multifunctional sensor at the medium-high frequency also gradually increases to 10 °, which is mainly because the molecular motion of the micro-nano porous PPy @ PU conductive film is accelerated along with the increase of the temperature, and the electrons are thermally activated, so that the inductive reactance phenomenon occurs between the conductive film and the single-sided electrode. Thus, temperature affects the behavior of the resistor by affecting intermolecular motion.
Figure 6e shows that as humidity increases, the impedance of the multifunction sensor also decreases.
Fig. 6f shows that a peak gradually appears at medium-high frequency with the increase of humidity, and when the humidity is 90 RH%, the phase angle of the multifunctional sensor is 45 °, and the water molecules are adsorbed to PPy @ PU with the increase of humidity by combining the analysis of the equivalent circuit diagram. H of water molecule decomposition+And H3O+The ion conduction is contributed, and the ion conduction process causes the appearance of capacitance arc, thereby influencing the capacitance behavior, so the humidity influences the capacitance behavior of the multifunctional sensor through the adsorption of water molecules, and further influences the impedance.
In conclusion, the pressure, the temperature and the humidity are independent and do not affect each other based on different mechanisms which affect the sensing function of the multifunctional sensor, and the electrochemical impedance spectrum and the equivalent circuit diagram are analyzed.
Claims (10)
1. A method for preparing a multifunctional sensor for synchronously measuring temperature, pressure and humidity comprises the following steps:
(1) pretreating the surface of the high-purity aluminum, taking the pretreated high-purity aluminum sheet as an anode and a titanium plate as a cathode, and performing electrochemical polishing in a mixed solution of perchloric acid and absolute ethyl alcohol to obtain an aluminum sheet with a smooth surface;
(2) carrying out primary oxidation in a mixed solution of phosphoric acid and oxalic acid by taking the aluminum sheet obtained in the step (1) as an anode and a titanium plate as a cathode; placing the aluminum oxide film with the aluminum substrate after primary oxidation in a mixed solution of chromium trioxide and phosphoric acid to remove generated aluminum oxide, and obtaining an aluminum sheet with regular pits on the surface;
(3) taking the aluminum sheet obtained in the step (2) as an anode, performing step-pressure reduction anodic oxidation under the condition that the condition is the same as that of primary oxidation, and after the oxidation is finished, performing chemical corrosion in a phosphoric acid solution to form a through hole anodic aluminum oxide template on the surface of the aluminum sheet;
(4) polymerizing pyrrole monomers onto the hole wall of the through hole anodic aluminum oxide template obtained in the step (3) by adopting a chemical in-situ polymerization method;
(5) spin-coating a flexible high polymer solution on the through-hole alumina template with the polypyrrole attached on the surface obtained in the step (4) by using a spin-coating method, and placing the template in a vacuum drying oven for high-temperature treatment under a vacuum condition, wherein the flexible high polymer is polymethyl methacrylate, polystyrene, polyurethane or polyacrylonitrile;
(6) placing the through hole anodized aluminum template with the aluminum sheet treated in the step (5) in a mixed solution of hydrochloric acid and copper chloride, and removing the aluminum sheet;
(7) placing the through hole anodic alumina template with polypyrrole and flexible high polymer attached on the surface in a phosphoric acid aqueous solution to remove the through hole anodic alumina template, and obtaining a regular porous flexible conductive film;
(8) and (4) packaging the fabric, the regular porous flexible conductive film obtained in the step (7), the fabric interdigital electrode and the superfine lead to obtain the multifunctional sensor for synchronously measuring the temperature, the pressure and the humidity.
2. The method according to claim 1, wherein in the step (1), the purity of the high-purity aluminum flake is higher than 99%, and the pretreatment comprises: ultrasonic cleaning in acetone for 5-15min, drying, and placing in 1mol/L NaOH solution for 10-20min to remove natural oxide layer on the surface; the mixed solution of perchloric acid and absolute ethyl alcohol is formed by mixing perchloric acid and absolute ethyl alcohol in a volume ratio of 1 (3.5-4.5), the voltage is 20-25V, the polishing time is 4-6min, and the temperature is 0-5 ℃.
3. The preparation method as claimed in claim 1, wherein in the step (2), during the primary oxidation, the concentration of oxalic acid in the mixed solution is 0.01-0.03M and the concentration of diluted phosphoric acid is 0.5-2 wt%, the oxidation voltage is 190-210V, the temperature is 0-5 ℃, and the oxidation time is 3-5 h; the mixed water solution of chromium trioxide and phosphoric acid for removing oxide film contains 12-20g/L CrO3And 4-10 wt% of H3PO4The temperature is 50-80 ℃.
4. The preparation method as claimed in claim 1, wherein in the step (3), the initial voltage range of the oxidation voltage is 190-210V, the depressurization rate is 1-3V/min, the target voltage range of depressurization is 0-70V, the concentration of the phosphoric acid solution is 3-10 wt%, the etching time is 3-4h, and the temperature is 25-45 ℃.
5. The preparation method according to claim 1, wherein in the step (4), the tapered anodic alumina template is immersed in a pyrrole aqueous solution with the concentration of 0.03-0.07M and magnetically stirred for 20-40min, and then a mixed aqueous solution containing 0.05-0.12M of p-toluenesulfonic acid and 0.05-0.10M of ferric trichloride with the same volume is added, the polymerization time is 40-80min, and the process is also carried out under the condition of magnetic stirring; the thickness of polypyrrole on the through hole anodic alumina template is 10nm-5 μm.
6. The method as claimed in claim 1, wherein in the step (5), the solvent of the solution of the flexible polymer is N, N-dimethylformamide, the mass fraction of the solute is 10-25 wt%, the rotation speed of the spin coater is 500-4000/min, the spin coating time is 10-30s, the temperature of the vacuum drying oven is 80-160 ℃, and the time is 1.5-3.5 h; the thickness of the flexible high polymer coating is 100nm-100 mu m.
7. The production method according to claim 1, wherein in the step (6), the mixed solution of hydrochloric acid and copper chloride has a hydrochloric acid concentration of 5 to 25 wt% and a copper chloride concentration of 0.05 to 0.15 mol/L.
8. The preparation method according to claim 1, wherein in the step (7), the mass fraction of the phosphoric acid aqueous solution is 10-30 wt%, the reaction temperature is 20-60 ℃, and the pore diameter of the regular porous flexible conductive film is 50-1000 nm.
9. The method of claim 1, wherein: in the step (8), the fabric of the fabric electrode is woven fabric, knitted fabric, non-woven fabric or a flexible high polymer film, the preparation method of the fabric electrode is to coat conductive copper, gold, platinum or titanium slurry on the fabric by adopting screen printing, or coat copper, platinum, titanium or a composite coating electrode thereof on the fabric by adopting magnetron sputtering method, the distance between the electrodes is 0.1-5mm, and the packaging method of the sensor is to paste flexible fabric adhesive tape or to bond the flexible conductive high polymer film and the fabric electrode together by adopting a hot pressing method.
10. A method for simultaneously measuring temperature, pressure, humidity using the multifunctional sensor prepared by the method of any one of claims 1 to 9, comprising the steps of:
(1) testing the electrochemical impedance spectrum of the multifunctional sensor under the conditions of different pressures, different temperatures and different humidities;
(2) constructing an equivalent circuit model for measuring the electrochemical impedance spectrum;
(3) fitting parameters of the equivalent circuit model by using the electrochemical impedance spectrum in the step (1) and the equivalent circuit model in the step (2) and combining electrochemical software;
(4) constructing a functional relation model of the equivalent circuit model parameters in the step (3) and corresponding pressure, temperature and humidity values;
(5) and (3) under certain pressure, temperature and humidity conditions, measuring the electrochemical impedance spectrum of the multifunctional sensor, fitting parameters of an equivalent circuit model corresponding to the electrochemical impedance spectrum, and calculating pressure, temperature and humidity data under the conditions by applying the functional relation model in the step (4).
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113970394A (en) * | 2021-10-22 | 2022-01-25 | 安徽大学 | Flexible piezoresistive sensor based on porous microstructure and preparation method thereof |
| CN114451602A (en) * | 2021-12-03 | 2022-05-10 | 天津工业大学 | Temperature and humidity sensing intelligent heating set |
| CN114674346A (en) * | 2022-03-24 | 2022-06-28 | 福建工程学院 | Preparation method of sensor and sensor |
| CN117091653A (en) * | 2023-08-24 | 2023-11-21 | 哈尔滨理工大学 | Double-parameter thin film sensor for safety monitoring of energy storage system and preparation method and application thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101105468A (en) * | 2007-04-30 | 2008-01-16 | 华南理工大学 | Porous anode alumina humidity sensor and its preparing process |
| TW201114813A (en) * | 2009-10-19 | 2011-05-01 | Ind Tech Res Inst | Method for one step immobilizing TiO2 crystalline nano-particles on polymer support and use of the same |
| CN102507660A (en) * | 2011-11-21 | 2012-06-20 | 电子科技大学 | Humidity-sensitive sensor based on aluminum oxide nanowire film and preparation method of humidity-sensitive sensor |
| CN103403177A (en) * | 2010-10-22 | 2013-11-20 | 弗里堡大学 | Sensor |
| CN105040065A (en) * | 2015-06-16 | 2015-11-11 | 天津工业大学 | Method for preparing neat porous anodic alumina film |
| CN107003266A (en) * | 2014-06-11 | 2017-08-01 | 帕克-汉尼芬公司 | Solid state electrode and sensor |
| CN109781311A (en) * | 2019-01-23 | 2019-05-21 | 济南大学 | A kind of flexible capacitance type pressure sensor and preparation method thereof |
-
2021
- 2021-07-14 CN CN202110796107.1A patent/CN113514106B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101105468A (en) * | 2007-04-30 | 2008-01-16 | 华南理工大学 | Porous anode alumina humidity sensor and its preparing process |
| TW201114813A (en) * | 2009-10-19 | 2011-05-01 | Ind Tech Res Inst | Method for one step immobilizing TiO2 crystalline nano-particles on polymer support and use of the same |
| CN103403177A (en) * | 2010-10-22 | 2013-11-20 | 弗里堡大学 | Sensor |
| CN102507660A (en) * | 2011-11-21 | 2012-06-20 | 电子科技大学 | Humidity-sensitive sensor based on aluminum oxide nanowire film and preparation method of humidity-sensitive sensor |
| CN107003266A (en) * | 2014-06-11 | 2017-08-01 | 帕克-汉尼芬公司 | Solid state electrode and sensor |
| CN105040065A (en) * | 2015-06-16 | 2015-11-11 | 天津工业大学 | Method for preparing neat porous anodic alumina film |
| CN109781311A (en) * | 2019-01-23 | 2019-05-21 | 济南大学 | A kind of flexible capacitance type pressure sensor and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| LU, YW: "Highly Sensitive Interlocked Piezoresistive Sensors Based on Ultrathin Ordered Nanocone Array Films and Their Sensitivity Simulation", 《ACS APPLIED MATERIALS & INTERFACES》 * |
| 鲁亚稳: "基于AAO模板的高聚物纳米阵列薄膜的研究进展", 《材料导报》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113970394A (en) * | 2021-10-22 | 2022-01-25 | 安徽大学 | Flexible piezoresistive sensor based on porous microstructure and preparation method thereof |
| CN114451602A (en) * | 2021-12-03 | 2022-05-10 | 天津工业大学 | Temperature and humidity sensing intelligent heating set |
| CN114674346A (en) * | 2022-03-24 | 2022-06-28 | 福建工程学院 | Preparation method of sensor and sensor |
| CN117091653A (en) * | 2023-08-24 | 2023-11-21 | 哈尔滨理工大学 | Double-parameter thin film sensor for safety monitoring of energy storage system and preparation method and application thereof |
| CN117091653B (en) * | 2023-08-24 | 2024-04-12 | 哈尔滨理工大学 | Double-parameter thin film sensor for safety monitoring of energy storage system and preparation method and application thereof |
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