CN113120884A - Graphene aerogel with sound absorption and audio recognition functions and application thereof - Google Patents

Graphene aerogel with sound absorption and audio recognition functions and application thereof Download PDF

Info

Publication number
CN113120884A
CN113120884A CN202110412355.1A CN202110412355A CN113120884A CN 113120884 A CN113120884 A CN 113120884A CN 202110412355 A CN202110412355 A CN 202110412355A CN 113120884 A CN113120884 A CN 113120884A
Authority
CN
China
Prior art keywords
graphene
sound absorption
graphene aerogel
aerogel
sound
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202110412355.1A
Other languages
Chinese (zh)
Other versions
CN113120884B (en
Inventor
陈南
李增领
曲良体
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing Institute of Technology BIT
Original Assignee
Beijing Institute of Technology BIT
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beijing Institute of Technology BIT filed Critical Beijing Institute of Technology BIT
Priority to CN202110412355.1A priority Critical patent/CN113120884B/en
Publication of CN113120884A publication Critical patent/CN113120884A/en
Application granted granted Critical
Publication of CN113120884B publication Critical patent/CN113120884B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/15—Nano-sized carbon materials
    • C01B32/182—Graphene
    • C01B32/184—Preparation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
    • B01J13/0091—Preparation of aerogels, e.g. xerogels
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2204/00—Structure or properties of graphene
    • C01B2204/20—Graphene characterized by its properties
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2204/00—Structure or properties of graphene
    • C01B2204/20—Graphene characterized by its properties
    • C01B2204/26—Mechanical properties

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Nanotechnology (AREA)
  • Inorganic Chemistry (AREA)
  • Carbon And Carbon Compounds (AREA)

Abstract

The invention relates to a graphene aerogel with sound absorption and audio identification functions and application thereof, and belongs to the technical field of sound absorption materials. Firstly, stirring and foaming a mixed solution of graphene oxide, a reducing agent and a foaming agent, then heating to perform partial reduction, freezing and freezing, and finally unfreezing to obtain partially reduced graphene oxide hydrogel; and mechanically compressing the partially reduced graphene oxide hydrogel according to the required compression degree, drying, and annealing to obtain the graphene aerogel. By changing the thickness and the compression degree of the graphene aerogel, the noise can be efficiently absorbed in any single frequency band within a wide frequency band range; graphene aerogels with different thicknesses and compression degrees are simply superposed and combined, so that multi-band efficient noise absorption within a wide frequency band range can be realized; the graphene aerogel can also be applied to an acoustic recognition device to realize recognition of specific frequency band audio.

Description

Graphene aerogel with sound absorption and audio recognition functions and application thereof
Technical Field
The invention relates to a graphene aerogel with sound absorption and audio identification functions and application thereof, and belongs to the technical field of sound absorption materials.
Background
Many three-dimensional (3D) porous materials have been devoted to achieving a greater range of audio absorption as sound absorbing materials, including sponges, aerogels, cellular plastics, and porous metal foams, among others. Due to poor controllability and accuracy of the process, noise absorption at specific frequencies is limited to acoustic metamaterials, helmholtz resonators, and perforated plates. Some researchers have designed ordered structures based on resonance to absorb noise at a given frequency. However, these designs are not only complex and expensive, but also have poor mechanical properties, and the harsh conditions of use limit the range of commercial applications. Admittedly, 3D porous materials are considered as a good choice of sound absorbing materials due to their unique structural advantages, including low density, excellent mechanical properties and high porosity. The synchronous multidirectional adjustment of the 3D porous material is realized through a reasonable and simple technology, and the method is very important for realizing the purpose of controllable change of the sound absorption performance of the sound absorption material.
The 3D porous graphene assembled by the nanosheets inherits the large surface area, excellent conductivity and good mechanical properties of single-layer graphene, and the nanoscale 3D framework structure can effectively consume sound energy, so that the 3D porous graphene becomes a potential 3D porous sound absorption material. However, none of the currently reported sound-absorbing materials can achieve efficient control of sound absorption at different frequencies over a wide frequency band, and also cannot achieve conversion from a single frequency to a plurality of frequency ranges in a simple manner. In addition, conversion of sound absorbing materials into acoustic identification materials has not been reported at present.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide the graphene aerogel with the sound absorption and audio recognition functions and the application thereof, wherein the single-frequency-band high-efficiency noise absorption of the material in a wider frequency band is realized by regulating and controlling the thickness and the compression degree of the material, and the multi-frequency-band high-efficiency noise absorption of the material in the wider frequency band can be realized by simply superposing and combining the materials with different thicknesses and compression degrees; in addition, the material also has an audio recognition function and can be applied to the field of acoustic recognition devices.
The purpose of the invention is realized by the following technical scheme.
The graphene aerogel with the sound absorption and audio recognition functions is prepared by the following method:
stirring and foaming the mixed solution of the graphene oxide, the reducing agent and the foaming agent to ensure that the volume after foaming is 1.5-2.5 times of the volume before foaming, and the interior of the mixture after foaming presents a spherical cellular structure; filling the foamed mixture into a mold, heating and reducing at 50-90 ℃, adding water with the volume not less than the volume of the black blocks into the mold when the mixture becomes black blocks and is separated from the inner wall of the mold, continuing heating and reducing for 8-10 h, freezing and icing at-20-10 ℃, piercing bubbles in hydrogel by using ice crystals to form a cross-linked and penetrated channel, and unfreezing at 50 ℃ below to obtain partially reduced graphene oxide hydrogel; and mechanically compressing the partially reduced graphene oxide hydrogel according to the required compression degree, then drying the partially reduced graphene oxide hydrogel in an environment below 60 ℃, and then annealing the partially reduced graphene oxide hydrogel at 180-220 ℃ for not less than 4 hours to obtain the graphene aerogel.
Further, the concentration of graphene oxide in the mixed solution is preferably 5mg/mL to 14 mg/mL.
Further, the reducing agent is used for reducing graphene oxide into graphene, preferably L-ascorbic acid, and the mass ratio of the reducing agent to the graphene oxide is (1.9-3): 1; the foaming agent is preferably octyl decyl alkyl glucoside, tween or sodium dodecyl sulfate, and the mass ratio of the foaming agent to the reducing agent is 1: (1.2-3.5).
Further, it is preferable to raise the temperature to 180 to 220 ℃ at a temperature raising rate of 1.5 to 4 ℃/min.
Further, the material of the mold is preferably glass or plastic.
A single-frequency-band graphene aerogel sound absorption material is characterized in that the sound absorption material only has one obvious sound absorption peak in a wide frequency band needing sound absorption, namely, the single-frequency-band high-efficiency noise absorption is realized, and the single-frequency-band sound absorption peak moves from high frequency to low frequency along with the increase of the thickness of graphene hydrogel under the condition that the compression degree is unchanged; under the condition that the thickness of the graphene hydrogel is not changed, the position of a single-frequency-band sound absorption peak moves from high frequency to low frequency along with the increase of the compression degree.
The utility model provides a multifrequency section graphite alkene aerogel sound absorbing material, sound absorbing material is formed by the same and different N graphite alkene aerogel stack combination of compression degree of thickness, perhaps forms by the same and different N graphite alkene aerogel stack combination of thickness of compression degree, and this sound absorbing material appears N in the wide band section of the sound absorption of needs and is showing the sound absorption peak, realizes the high-efficient noise absorption of multifrequency section promptly, and the sound absorption coefficient peak value does not obviously reduce, and whole sound absorption coefficient improves.
Further, the wide frequency band required to absorb sound is preferably 2000Hz to 6000 Hz.
When the graphene aerogel is used as a single-frequency-band or multi-frequency-band sound-absorbing material, the sound-absorbing peak position of each frequency band can be predicted by adopting the following formula;
(1) the thickness of the graphene aerogel is 1cm, and the compression factor ncWhen the ratio is more than or equal to 1:
Figure BDA0003024656940000031
wherein y is the theoretical sound absorption peak value, y0Is 3352Hz, A1Is 2213Hz, ncFor a compression factor, n0Is constant 0.80, t1Is a constant of 5.0;
(2) when the graphene aerogel thickness T is greater than 0 and the compression factor is 2 (the compression factor is the ratio of the height before compression to the height after compression):
Figure BDA0003024656940000032
wherein y is the theoretical sound absorption peak value, y0Is 1845Hz, A1Is 3227Hz, T is the thickness of the graphene aerogel (unit is mm), T0Is 10mm, t1Is a constant14.3。
The graphene aerogel disclosed by the invention can be applied to an acoustic recognition device, such as an audio signal recognition device based on the graphene aerogel, wherein the device comprises an audio signal generator, a signal amplifier, the graphene aerogel, an insulating substrate (such as a plastic plate or a glass plate), an electrochemical workstation and a computer;
the graphene aerogel is placed on the insulating substrate, one ends of two leads are connected with two ends of the graphene aerogel in a one-to-one correspondence mode through conductive adhesives, the other end of one lead is connected with two electrodes of an electrochemical workstation, the other end of the other lead is connected with the remaining electrode of the electrochemical workstation, the electrochemical workstation is connected with a computer, an audio signal generator is connected with a signal amplifier, and the signal amplifier is located right above the graphene aerogel.
The acoustic signal that the audio signal amplifier produced transmits graphene aerogel after signal amplifier enlargies, thereby graphite alkene aerogel makes its resistance change to the vibration of different acoustic signal inside emergence different degree, thereby the vibration is big then the resistivity change big so that the electric signal response degree is also big, convert acoustic signal into electrical signal and transmit for the computer through the electrochemistry workstation, can realize the recognition function to the specific frequency channel audio frequency according to electrical signal and audio signal's relation.
Has the advantages that:
(1) the graphene hydrogel obtained by a foaming method and an ice template has good plasticity, can be compressed and customized in any proportion, and is subjected to normal-pressure drying and annealing treatment to obtain the graphene aerogel.
(2) The graphene aerogel disclosed by the invention has good structural stability and elasticity, the compressive strain can reach 90%, and under the condition that the compressive strain is 70%, the graphene aerogel still keeps good resilience after being circularly compressed for 500 times. This graphite alkene aerogel can be used as sound absorbing material, and through changing thickness and compression degree, can realize the high-efficient absorbed noise of arbitrary single-band in the broad frequency range, and the biggest sound absorption coefficient is close to 100% to carry out simple stack combination with the graphite alkene aerogel of different thickness and compression degree, can follow the single-frequency and absorb the multifrequency and absorb the extension and absorb, can realize the high-efficient absorbed noise of the multifrequency section in the broad frequency range promptly, and the sound absorption efficiency generally improves.
(3) The invention provides a model for predicting peak positions, explains the mechanism of peak displacement by changing compression factors and thicknesses, and provides a theoretical basis for designing the graphene aerogel capable of efficiently absorbing noise in a specific frequency band.
(4) The graphene aerogel disclosed by the invention can be applied to an acoustic recognition device, opens up a new way for applying the graphene aerogel and has a wide practical application prospect.
(5) The graphene aerogel disclosed by the invention can be prepared commercially on a large scale, and is simple in preparation process, environment-friendly, energy-saving, low in cost and high in efficiency.
Drawings
FIG. 1 is a comparison chart of 5 graphene hydrogels with different heights prepared in examples 1-5 before and after mechanical compression.
FIG. 2 is a Scanning Electron Microscope (SEM) comparison of 5 kinds of graphene aerogels with different compression degrees prepared in examples 1 to 5; FIGS. a, c, d, e and f correspond to examples 1 to 5 one by one in order, FIG. b is a partially enlarged view of FIG. a, FIG. b is a scale of 200nm, and the remainder are scales of 200 μm.
Fig. 3 is a comparison graph of XRD spectra of the graphene aerogel, the partially reduced graphene oxide aerogel and graphene oxide in example 1.
Fig. 4 is a comparison graph of the compression performance test results of 5 kinds of graphene aerogels with different compression degrees prepared in embodiments 1 to 5.
Fig. 5 is a comparative graph of the compression performance test results of the graphene aerogel prepared in example 4 under different compression strains.
Fig. 6 is a comparison graph of the hydrophobicity test results of 5 kinds of graphene aerogels with different compression degrees prepared in examples 1 to 5.
FIG. 7 is a graph comparing the sound absorption performance and the compression degree of 5 graphene aerogels with different compression degrees prepared in examples 1 to 5.
Fig. 8 is a graph comparing the sound absorption performance and thickness of 4 graphene aerogels with different thicknesses prepared in example 6.
FIG. 9 is a sound absorption performance diagram of a two-frequency-band graphene aerogel sound absorption material formed by overlapping and combining graphene aerogels prepared in embodiment 1-2.
FIG. 10 is a sound absorption performance diagram of a three-band graphene aerogel sound absorption material formed by superposing and combining graphene aerogels prepared in the embodiment 1-3.
FIG. 11 is a sound absorption performance diagram of a four-band graphene aerogel sound absorption material formed by overlapping and combining graphene aerogels prepared according to embodiments 1 to 4.
FIG. 12 is a sound absorption performance diagram of a five-frequency-band graphene aerogel sound absorption material formed by overlapping and combining graphene aerogels prepared according to embodiment 1-5.
Fig. 13 is a response curve diagram of 5 graphene aerogels with different compression degrees prepared in examples 1 to 5 for different audio signals within 60 s.
Fig. 14 is a comparison graph of the response degree of 5 kinds of graphene aerogels with different compression degrees prepared in examples 1 to 5 to different audio signals.
Detailed Description
The present invention is further illustrated by the following detailed description, wherein the processes are conventional unless otherwise specified, and the starting materials are commercially available from a public source without further specification.
Example 1
(1) Adding 66.7mL of a graphene oxide solution with a concentration of 18mg/mL, 33.3mL of an aqueous solution containing 2.4g L-ascorbic acid, and 8mL of an octyldecyl alkyl glycoside containing 1.6g to a 500mL beaker, and foaming the mixed solution by high-speed stirring so that the volume after foaming is 2 times of the volume before foaming;
(2) filling the foamed mixture into a glass material mold, heating and reducing the foamed mixture in an oven at 60 ℃, adding deionized water with the volume not less than the volume of the black block into the mold when the mixture becomes black block and is separated from the mold, continuing heating and reducing the mixture for 10 hours, freezing the mixture at (-20) DEG C to completely freeze the mixture, and unfreezing the mixture at room temperature (25 ℃) to obtain partially reduced graphene oxide hydrogel with the height of 1 cm;
(3) putting the partially reduced graphene oxide hydrogel into a 50 ℃ oven for drying for 10h, transferring the partially reduced graphene oxide hydrogel into a muffle furnace, heating the partially reduced graphene oxide hydrogel to 200 ℃ at the heating rate of 2 ℃/min, and annealing and reducing the partially reduced graphene oxide hydrogel for 4h at the temperature of 200 ℃ to obtain the partially reduced graphene oxide hydrogel with the density of 8.09mg/cm3Graphene aerogel, this graphene aerogel is designated as cGA 1.
Example 2
(1) Same as in example 1, step (1);
(2) preparing a partially reduced graphene oxide hydrogel having a height of 2cm according to the conditions of the step (2) of example 1;
(3) compressing the partially reduced graphene oxide hydrogel from 2cm to 1cm, drying in a 50 ℃ oven for 10h, transferring to a muffle furnace, heating to 200 ℃ at a heating rate of 2 ℃/min, and annealing and reducing at 200 ℃ for 4h to obtain the graphene oxide hydrogel with the density of 16.2mg/cm3The graphene aerogel of (a), this graphene aerogel is abbreviated as cGA 2.
Example 3
(1) Same as in example 1, step (1);
(2) preparing a partially reduced graphene oxide hydrogel with a height of 4cm according to the conditions of the step (2) of example 1;
(3) compressing the partially reduced graphene oxide hydrogel from 4cm to 1cm, drying in a 50 ℃ oven for 10h, transferring to a muffle furnace, heating to 200 ℃ at a heating rate of 2 ℃/min, and annealing and reducing at 200 ℃ for 4h to obtain the graphene oxide hydrogel with the density of 32.7mg/cm3The graphene aerogel of (a), this graphene aerogel is abbreviated as cGA 4.
Example 4
(1) Same as in example 1, step (1);
(2) preparing a partially reduced graphene oxide hydrogel with a height of 8cm according to the conditions of the step (2) of example 1;
(3) partially reducingAfter the graphene oxide hydrogel is compressed to 1cm from 8cm, the graphene oxide hydrogel is firstly put into a 50 ℃ oven for drying for 10h, then is transferred into a muffle furnace and is heated to 200 ℃ at the heating rate of 2 ℃/min, and is annealed and reduced for 4h at 200 ℃ to obtain the graphene oxide hydrogel with the density of 64.4mg/cm3The graphene aerogel of (a), this graphene aerogel is abbreviated as cGA 8.
Example 5
(1) Same as in example 1, step (1);
(2) preparing a partially reduced graphene oxide hydrogel with a height of 16cm according to the conditions of the step (2) of example 1;
(3) compressing the partially reduced graphene oxide hydrogel from 16cm to 1cm, drying in a 50 ℃ oven for 10h, transferring to a muffle furnace, heating to 200 ℃ at a heating rate of 2 ℃/min, and annealing and reducing at 200 ℃ for 4h to obtain the graphene oxide hydrogel with the density of 128.3mg/cm3The graphene aerogel of (a), this graphene aerogel is abbreviated as cGA 16.
Example 6
(1) Same as in example 1, step (1);
(2) partially reduced graphene oxide hydrogels having heights of 2cm, 4cm, 6cm and 8cm were prepared according to the conditions of the step (2) of example 1, respectively;
(3) sequentially compressing the partially reduced graphene oxide hydrogel with the height of 2cm, 4cm, 6cm and 8cm to 1cm, 2cm, 3cm and 4cm, respectively putting the partially reduced graphene oxide hydrogel into a 50 ℃ oven for drying for 10 hours, then transferring the partially reduced graphene oxide hydrogel into a muffle furnace, heating the partially reduced graphene oxide hydrogel to 200 ℃ at the heating rate of 2 ℃/min, and annealing and reducing the partially reduced graphene oxide hydrogel at 200 ℃ for 4 hours to obtain 4 graphene aerogels with the same compression degree and different thicknesses.
Example 7
(1) Adding 66.7mL of a graphene oxide solution with a concentration of 18mg/mL, 33.3mL of an aqueous solution containing 2.4g L-ascorbic acid, and 8mL of an octyldecyl alkyl glycoside containing 1.6g to a 500mL beaker, and foaming the mixed solution by high-speed stirring so that the volume after foaming is 2.5 times of the volume before foaming;
(2) filling the foamed mixture into a glass material mold, heating and reducing the foamed mixture in a 60 ℃ oven, adding deionized water with the volume not less than the volume of the black block into the mold when the mixture becomes black block and is separated from the mold, continuing heating and reducing the mixture for 10 hours, freezing the mixture at the temperature of minus 20 ℃ to completely freeze the mixture, and unfreezing the mixture at room temperature to obtain partially reduced graphene oxide hydrogel with the height of 1 cm;
(3) putting the partially reduced graphene oxide hydrogel into a 50 ℃ oven for drying for 10h, transferring the partially reduced graphene oxide hydrogel into a muffle furnace, heating the partially reduced graphene oxide hydrogel to 200 ℃ at the heating rate of 2 ℃/min, and carrying out annealing reduction for 4h at the temperature of 200 ℃ to obtain the partially reduced graphene oxide hydrogel with the density of 6.50mg/cm3The graphene aerogel of (1).
Example 8
(1) Adding 66.7mL of a graphene oxide solution with a concentration of 18mg/mL, 33.3mL of an aqueous solution containing 2.4g L-ascorbic acid, and 6mL of an octyldecyl alkyl glycoside containing 1.2g to a 500mL beaker, and foaming the mixed solution by high-speed stirring so that the volume after foaming is 1.5 times of the volume before foaming;
(2) filling the foamed mixture into a glass material mold, heating and reducing the foamed mixture in a 60 ℃ oven, adding deionized water with the volume not less than the volume of the black block into the mold when the mixture becomes black block and is separated from the mold, continuing heating and reducing the mixture for 10 hours, freezing the mixture at the temperature of minus 20 ℃ to completely freeze the mixture, and unfreezing the mixture at room temperature to obtain partially reduced graphene oxide hydrogel with the height of 1 cm;
(3) putting the partially reduced graphene oxide hydrogel into a 50 ℃ oven for drying for 12h, transferring the partially reduced graphene oxide hydrogel into a muffle furnace, heating the partially reduced graphene oxide hydrogel to 200 ℃ at the heating rate of 2 ℃/min, and annealing and reducing the partially reduced graphene oxide hydrogel for 4h at the temperature of 200 ℃ to obtain the partially reduced graphene oxide hydrogel with the density of 10.81mg/cm3The graphene aerogel of (1).
Example 9
(1) Adding 50mL of a graphene oxide solution with a concentration of 12mg/mL, 50mL of an aqueous solution containing 1.2g L-ascorbic acid and 2mL of an octyldecyl glucoside with a concentration of 0.4g into a 500mL beaker, and foaming the mixed solution by high-speed stirring so that the volume after foaming is 2 times of the volume before foaming;
(2) filling the foamed mixture into a glass material mold, heating and reducing the foamed mixture in a 70 ℃ oven, adding deionized water with the volume not less than the volume of the black block into the mold when the mixture becomes black block and is separated from the mold, continuing heating and reducing the mixture for 8 hours, freezing the mixture at the temperature of minus 10 ℃ to completely freeze the mixture, and unfreezing the mixture at room temperature to obtain partially reduced graphene oxide hydrogel with the height of 1 cm;
(3) putting the partially reduced graphene oxide hydrogel into a 50 ℃ oven for drying for 10h, then transferring the partially reduced graphene oxide hydrogel into a muffle furnace, heating the partially reduced graphene oxide hydrogel to 210 ℃ at the heating rate of 2 ℃/min, and carrying out annealing reduction for 5h at 210 ℃ to obtain the graphene oxide hydrogel with the density of 3.99mg/cm3The graphene aerogel of (1).
The 5 graphene hydrogels with different heights prepared in examples 1 to 5 were mechanically compressed to the same height, so as to obtain graphene hydrogels with different compression degrees and thicknesses of 1cm in 5, as shown in fig. 1.
As can be seen in fig. 2a, the graphene sheets in cGA1 are stacked around the bubbles to form a regular 3D structure, this 3D bubble structure resembles open cellular cavities, and the cellular cavities are connected to each other by interleaved graphene sheets; as can be seen from fig. 2b, the wall thickness of the cGA1 honeycomb cells is about 20 nm. Fig. 2c to 2f show axial SEM images of cGA2, cGA4, cGA8 and cGA16 parallel to the direction of compression, with spherical honeycomb shaped cells gradually forming an ordered ellipsoid shaped cell as the degree of compression increases.
A typical sharp diffraction peak of graphene oxide occurs around 10.28 °; due to sp in the self-assembly process of graphene2The conjugate recovery and the pi-pi stacking interaction are realized, and the wide diffraction peak of the partially reduced graphene oxide aerogel (namely the partially reduced graphene oxide hydrogel is dried but not annealed) is 23.44 degrees; after annealing at 200 ℃, the diffraction peak of graphene oxide completely disappeared, indicating that graphene oxide was completely reduced to graphene, as shown in fig. 3.
As can be seen from fig. 4, the stress-strain curves of the 5 graphene aerogels with different degrees of compression show typical viscoelastic behavior, which is represented by a hysteresis loop between the loading and unloading curves, wherein the maximum stress range at 70% compression is 14kPa to 900kPa, indicating that the prepared 5 graphene aerogels with different degrees of compression can be highly compressed and can be completely recovered. cGA8 of fig. 5 show that the prepared graphene aerogel has excellent compressibility at different strain levels, as indicated by the compression and unloading curves of the aerogel under different compressive strains. The excellent mechanical property is the important performance of the graphene aerogel as the sound absorption material, and the stable mechanical property improves the pressure resistance and the mechanical strength of the sound absorption material, so that the service life is prolonged.
According to the test results of fig. 6, the maximum water contact angles of cGA1-cGA16 are 116.1 °, 124.5 °, 115.6 °, 114.7 °, and 116.2 °, respectively, which indicates that the prepared graphene aerogel has excellent hydrophobicity, and the excellent hydrophobicity can increase the use range of the graphene aerogel, reduce the corrosion of microorganisms, and thus improve the service life of the sound absorption material.
The graphene aerogel prepared in the embodiment 1-5 is placed on an alcohol burner to be combusted, the appearance of the graphene aerogel is basically kept unchanged after 60 seconds of combustion, the volume of the graphene aerogel is slightly reduced after 180 seconds of combustion, and the prepared graphene aerogel has better flame retardance.
According to the test results of fig. 7, the sound absorption peak positions of cGA1-cGA16 are 5523Hz, 5072Hz, 4416Hz, 4008Hz, and 3408Hz respectively, that is, when the thicknesses of the graphene aerogel are the same, the sound absorption peak positions move from a high frequency region to a low frequency region along with the increase of the compression degree, which indicates that the sound absorption peak positions of the graphene aerogel can be customized by changing the compression degree, so that the sound in a specific frequency band can be efficiently absorbed. Wherein, as the degree of compression increases, the alpha of the graphene aerogelmaxThe (maximum sound absorption coefficient value) is reduced from 98.7% to 95.5%, which shows that the effect of changing the compression degree on the sound absorption effect of the high-porosity graphene aerogel at specific frequency noise is relatively small.
According to the test results of fig. 8, the sound absorption peak positions of the graphene aerogels with the thicknesses of 10mm, 20mm, 30mm and 40mm are 5072Hz, 3288Hz, 2680Hz and 2240Hz respectively, that is, when the compression degrees of the graphene aerogels are the same, the sound absorption peak position moves from the high frequency region to the low frequency region along with the increase of the thicknesses, which shows that the sound absorption peak position of the graphene aerogel can be customized by changing the thicknesses of the graphene aerogels, so that the sound absorption peak positions can be actually customizedThe sound of a specific frequency band is efficiently absorbed. Wherein alpha of the graphene aerogelmaxThe attenuation from 98.5% to 94.4% with the increase of the thickness indicates that the influence of the change of the thickness on the sound absorption effect of the high-porosity graphene aerogel at specific frequency noise is small.
cGA1 and cGA2 are overlapped to form a two-frequency-band graphene aerogel sound-absorbing material, the sound-absorbing material is abbreviated as cGA1-2, and the sound-absorbing performance of the sound-absorbing material is shown in fig. 9. The sound absorption curve of fig. 9 has two distinct absorption peaks, one cGA1 peak moving from 5523Hz to 5276Hz, and one cGA2 peak moving from 5072Hz to 2860 Hz. 5276 the Hz peak position is due to the lower peak position of cGA1 when section cGA1 is coupled with section cGA 2; the 2860Hz peak position is due to the fact that coupling of section cGA2 with section cGA1 results in increased tortuosity and thickness, resulting in a lower frequency of peak position occurrences.
On the basis of cGA1-2, cGA4 is added to form a three-band graphene aerogel sound-absorbing material, which is abbreviated as cGA1-2-4, and the sound-absorbing performance of the material is shown in fig. 10. As can be seen from fig. 10, after cGA1, cGA2, and cGA4 are coupled, the peak position of cGA4 is shifted from 4416Hz to 2632Hz, the peak position of cGA1 is shifted to 5500Hz in the high frequency region, and the peak position of cGA2 is shifted to 3882Hz in the high frequency region.
On the basis of cGA1-2-4, cGA8 is continuously added to form a four-frequency-band graphene aerogel sound-absorbing material, which is abbreviated as cGA1-2-4-8, and the sound-absorbing performance of the material is shown in fig. 11. As can be seen from fig. 11, after cGA1, cGA2, cGA4 and cGA8 are coupled, the peak position of cGA8 is shifted from 4008Hz to 2512Hz, and the peak positions of cGA1 to cGA4 are shifted to 5805Hz, 4291Hz and 3185Hz, respectively, in the high frequency region.
On the basis of cGA1-2-4-8, cGA16 is continuously added to form a five-frequency-band graphene aerogel sound-absorbing material, which is abbreviated as cGA1-2-4-8-16, and the sound-absorbing performance of the sound-absorbing material is shown in fig. 12. As can be seen from FIG. 12, after cGA1, cGA2, cGA4, cGA8 and cGA16 are coupled, the peak position of cGA16 is shifted from 3408Hz to 2359Hz, and the peak positions of cGA1 to cGA8 are shifted to 5949Hz, 4835Hz, 4098Hz and 2888Hz respectively in the high frequency region.
In the multiband graphite alkene aerogel acoustic absorbent, the partial peak position of graphite alkene aerogel of different compression degree moves to lower frequency range region along with the increase of compression degree, and this is the same with single-frequency range graphite alkene aerogel acoustic absorbent's peak position change trend. When high-density graphene aerogel is further used in combination with cGA1-x, the position of each absorption peak in cGA1-x is shifted to a high-frequency region, and the position of the absorption peak of a newly added part is shifted to a low-frequency region. Therefore, the distribution frequency of some part of graphene aerogel in the multiband graphene aerogel sound-absorbing material can be predicted by fitting a curve, and then selective superposition of different graphene aerogels can realize targeted effective absorption under the distributed frequency, so that unnecessary frequency can be selectively eliminated according to needs.
The cylindrical graphene aerogel with the diameter of 30mm and the height of 10mm prepared in the embodiment is placed on an insulating substrate (a selected glass plate), one end of each of two wires (selected copper foils) is connected with two ends of the graphene aerogel in a one-to-one correspondence mode through conductive adhesive, the other end of one wire is connected with two electrodes of an electrochemical workstation (model CHI 760), the other end of the other wire is connected with the remaining electrode of the electrochemical workstation, the electrochemical workstation is connected with a computer, an audio signal generator (a selected fixed-frequency pulse signal transmitter, model ZC5820) is connected with a signal amplifier (a selected loudspeaker), and the signal amplifier is located 10cm above the graphene aerogel.
The audio signal generator performs acoustic output for 1s at a fixed frequency and with a pulse interval of 3s to verify relative signal strength and long-term stability, and records the current response of the graphene aerogel to different acoustic frequencies under a constant bias of 1V to construct a prototype sensor for audio signal identification. 1000Hz, 2000Hz, 3000Hz, 4000Hz, 5000Hz and 6000Hz were selected as fixed detection points, and then each graphene aerogel was tested and two fixed frequency detection points close to the maximum signal frequency range were selected. The current change was synchronized with the pulse signal change applied to the graphene aerogel and remained stable for 60 s. For sounds of different frequencies, different current signals can be detected, so that the response intensities of cGA1-cGA16 to the sounds of different frequencies can be obtained, as shown in fig. 13. As can be seen from the test results of fig. 13, the response ratios (maximum signal/minimum signal) of cGA1, cGA2, cGA4, cGA8, and cGA16 were 83, 13, 59, 83, and 10, respectively, indicating that the prepared graphene aerogel has a strong ability to recognize sounds of different frequencies. The simulated values of the maximum response frequencies (identification frequencies) of cGA1, cGA2, cGA4, cGA8, and cGA16 were 5532Hz, 4869Hz, 4430Hz, 3944Hz, and 3675Hz, respectively, as shown in fig. 14. When the sound wave passes through the graphene aerogel, the vibration of the graphene nanosheets inside the graphene aerogel can be caused, so that the resistance of the graphene aerogel is changed, the vibration is larger, the resistivity of the graphene aerogel is larger, and the electric signal response ratio is also larger. Therefore, when an appropriate audio signal passes through the graphene aerogel, the strongest electrical signal response is generated, and therefore identification of a specific audio signal is achieved.
In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The utility model provides a graphite alkene aerogel with inhale sound and audio frequency recognition function which characterized in that: the graphene aerogel is prepared by adopting the following method,
stirring and foaming the mixed solution of the graphene oxide, the reducing agent and the foaming agent to enable the volume after foaming to be 1.5-2.5 times of the volume before foaming; filling the foamed mixture into a mold, heating and reducing at 50-90 ℃, adding water with the volume not less than the volume of the black block into the mold when the mixture becomes the black block and is separated from the inner wall of the mold, continuing heating and reducing for 8-10 h, freezing and icing at-20-10 ℃, and unfreezing below 50 ℃ to obtain partially reduced graphene oxide hydrogel; and mechanically compressing the partially reduced graphene oxide hydrogel according to the required compression degree, drying the partially reduced graphene oxide hydrogel at the temperature of below 60 ℃, and then annealing the partially reduced graphene oxide hydrogel at the temperature of between 180 and 220 ℃ for not less than 4 hours to obtain the graphene aerogel.
2. The graphene aerogel with sound absorption and audio recognition functions according to claim 1, wherein: in the mixed solution, the concentration of the graphene oxide is 5 mg/mL-14 mg/mL.
3. The graphene aerogel with sound absorption and audio recognition functions according to claim 1, wherein: the reducing agent is L-ascorbic acid, and the mass ratio of the reducing agent to the graphene oxide is (1.9-3): 1; the foaming agent is octyl decyl alkyl glucoside, tween or sodium dodecyl sulfate, and the mass ratio of the foaming agent to the reducing agent is 1: (1.2-3.5).
4. The graphene aerogel with sound absorption and audio recognition functions according to claim 1, wherein: the temperature is increased to 180-220 ℃ at the temperature rising rate of 1.5-4 ℃/min.
5. The graphene aerogel with sound absorption and audio recognition functions according to claim 1, wherein: the mould is made of glass or plastic.
6. The utility model provides a graphite alkene aerogel acoustic material which characterized in that: the sound absorbing material is the graphene aerogel of any one of claims 1 to 5, and the sound absorbing material has a significant sound absorption peak in a wide frequency band needing sound absorption to realize single frequency band sound absorption;
or, the sound-absorbing material is formed by superposing and combining N pieces of graphene aerogels according to any one of claims 1 to 5, wherein the N pieces of graphene aerogels have the same thickness but different compression degrees, N significant sound-absorbing peaks appear in a wide frequency band needing sound absorption to realize multi-band sound absorption, and N is an integer greater than or equal to 2;
or, the sound-absorbing material is formed by superposing and combining N pieces of graphene aerogels according to any one of claims 1 to 5, wherein the N pieces of graphene aerogels have the same compression degree but different thicknesses, N significant sound-absorbing peaks appear in a wide frequency band needing sound absorption to realize multi-band sound absorption, and N is an integer greater than or equal to 2.
7. The graphene aerogel sound absorbing material of claim 6, wherein: the frequency range of the wide frequency band needing sound absorption is 2000 Hz-6000 Hz.
8. The graphene aerogel sound absorbing material of claim 6, wherein: predicting the positions of 1 or N sound absorption peaks appearing in the sound absorption material by adopting the following formula;
(1) the thickness of the graphene aerogel is 1cm, and the compression factor ncWhen the ratio is more than or equal to 1:
Figure FDA0003024656930000021
wherein y is the theoretical sound absorption peak value, y0Is 3352Hz, A1Is 2213Hz, ncFor a compression factor, n0Is constant 0.80, t1Is a constant of 5.0;
(2) graphene aerogel thickness T is greater than 0, and when the compression factor is 2:
Figure FDA0003024656930000022
wherein y is the theoretical sound absorption peak value, y0Is 1845Hz, A1Is 3227Hz, T is the thickness of the graphene aerogel, T0Is 10mm, t1Is constant 14.3.
9. Use of the graphene aerogel according to any one of claims 1 to 5 in an acoustic recognition device.
10. Use of the graphene aerogel according to claim 9 in an acoustic identification device, wherein: the acoustic identification device comprises an audio signal generator, a signal amplifier, the graphene aerogel, an insulating substrate, an electrochemical workstation and a computer;
the graphene aerogel is placed on the insulating substrate, one ends of two leads are connected with two ends of the graphene aerogel in a one-to-one correspondence mode through conductive adhesives, the other end of one lead is connected with two electrodes of an electrochemical workstation, the other end of the other lead is connected with the remaining electrode of the electrochemical workstation, the electrochemical workstation is connected with a computer, an audio signal generator is connected with a signal amplifier, and the signal amplifier is located right above the graphene aerogel.
CN202110412355.1A 2021-04-16 2021-04-16 Graphene aerogel with sound absorption and audio recognition functions and application thereof Active CN113120884B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110412355.1A CN113120884B (en) 2021-04-16 2021-04-16 Graphene aerogel with sound absorption and audio recognition functions and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110412355.1A CN113120884B (en) 2021-04-16 2021-04-16 Graphene aerogel with sound absorption and audio recognition functions and application thereof

Publications (2)

Publication Number Publication Date
CN113120884A true CN113120884A (en) 2021-07-16
CN113120884B CN113120884B (en) 2022-10-28

Family

ID=76776861

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110412355.1A Active CN113120884B (en) 2021-04-16 2021-04-16 Graphene aerogel with sound absorption and audio recognition functions and application thereof

Country Status (1)

Country Link
CN (1) CN113120884B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113860309A (en) * 2021-10-28 2021-12-31 赛轮集团股份有限公司 Aerogel foam with silencing function, preparation method thereof and tire
CN115893388A (en) * 2023-02-10 2023-04-04 青岛科技大学 High-modulus and high-elasticity graphene foam material and preparation method and application thereof

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106517160A (en) * 2016-11-22 2017-03-22 青岛科技大学 Method for preparing isotropic superelastic graphene aerogel
CN108046241A (en) * 2017-12-18 2018-05-18 苏州大学 A kind of 3D printing surpasses the method for poroelasticity graphene aerogel
CN109734076A (en) * 2018-12-28 2019-05-10 北京理工大学 A kind of preparation method of large area high intensity super-elasticity grapheme foam material
CN110127674A (en) * 2019-06-27 2019-08-16 中素新科技有限公司 The production method of graphene aerogel
CN110327851A (en) * 2019-06-27 2019-10-15 中素新科技有限公司 Elastic graphite alkene aeroge and its preparation method and application
WO2020130499A2 (en) * 2018-12-21 2020-06-25 한국과학기술원 Porous structure-based graphene foam and manufacturing method therefor

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106517160A (en) * 2016-11-22 2017-03-22 青岛科技大学 Method for preparing isotropic superelastic graphene aerogel
CN108046241A (en) * 2017-12-18 2018-05-18 苏州大学 A kind of 3D printing surpasses the method for poroelasticity graphene aerogel
WO2020130499A2 (en) * 2018-12-21 2020-06-25 한국과학기술원 Porous structure-based graphene foam and manufacturing method therefor
CN109734076A (en) * 2018-12-28 2019-05-10 北京理工大学 A kind of preparation method of large area high intensity super-elasticity grapheme foam material
CN110127674A (en) * 2019-06-27 2019-08-16 中素新科技有限公司 The production method of graphene aerogel
CN110327851A (en) * 2019-06-27 2019-10-15 中素新科技有限公司 Elastic graphite alkene aeroge and its preparation method and application

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113860309A (en) * 2021-10-28 2021-12-31 赛轮集团股份有限公司 Aerogel foam with silencing function, preparation method thereof and tire
CN115893388A (en) * 2023-02-10 2023-04-04 青岛科技大学 High-modulus and high-elasticity graphene foam material and preparation method and application thereof
CN115893388B (en) * 2023-02-10 2024-06-11 青岛科技大学 High-modulus and high-elasticity graphene foam material and preparation method and application thereof

Also Published As

Publication number Publication date
CN113120884B (en) 2022-10-28

Similar Documents

Publication Publication Date Title
CN113120884B (en) Graphene aerogel with sound absorption and audio recognition functions and application thereof
Oh et al. Self-aligned and hierarchically porous graphene-polyurethane foams for acoustic wave absorption
Zhao et al. Pore structure control of mesoporous carbon as supercapacitor material
WO2017190417A1 (en) Method for preparing thick and dense graphene-based electrode
CN110183718B (en) Preparation method of three-dimensional porous double-crosslinked polyaniline/graphene composite xerogel
CN109592964B (en) Elasticity-controllable graphene aerogel for electromagnetic shielding and preparation method thereof
CN103440995A (en) Electrode material for super capacitor and preparing method thereof
CN102432720B (en) Preparation method for graphene based compound hydrogel modified with poly (N-isopropylacrylamide)
CN103787327A (en) One-step preparation method of hollow spherical porous graphite for supercapacitor
CN106024413A (en) Super capacitor device made of graphitized nitrogen doped porous nanometer sheet carbon material
Kang et al. Compression strain-dependent tubular carbon nanofibers/graphene aerogel absorber with ultrabroad absorption band
CN111454691B (en) Graphene/amorphous titanium dioxide nanorod composite material, preparation method and application thereof
CN115424870B (en) Biomass-derived carbon material and preparation method and application thereof
CN107161979B (en) Carbon-based nanobelt porous material, and preparation method and application thereof
KR20100046445A (en) Method for purificating carbon nanotube and electromagnetic wave absorption material to include carbon nanotube that fabricated using the same
CN115838165B (en) Hard carbon negative electrode material, preparation method thereof and secondary battery
CN107215871A (en) A kind of preparation method of activated carbon for super capacitors
CN112265982A (en) Preparation method of N-doped graphene/graphene nanoribbon composite aerogel
Liu et al. Celery-derived porous carbon materials for superior performance supercapacitors
CN109293939B (en) Preparation method of ZIF-67 with hierarchical pore structure and preparation method of honeycomb-like carbon/cobalt wave-absorbing material
CN107010619A (en) A kind of preparation method taken into account sound insulation and be electromagnetically shielded difunctional graphene paper
CN105016337A (en) Active carbon material used for supercapacitor electrodes and preparation method thereof
CN112194132A (en) Preparation method and application of iron-modified carbon microsphere/carbon nanosheet composite porous carbon based on moso bamboo hydrothermal carbonization
Liu et al. Capacitive performances of reduced graphene oxide hydrogel prepared by using sodium hypophosphite as reducer
CN109336083B (en) Method for controllably preparing foam carbon/carbon nanotube composite material by high internal phase emulsion template method

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant