CN101572191B - V2O5-ordered mesoporous carbon composite material and preparation method thereof - Google Patents

V2O5-ordered mesoporous carbon composite material and preparation method thereof Download PDF

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CN101572191B
CN101572191B CN2009100625242A CN200910062524A CN101572191B CN 101572191 B CN101572191 B CN 101572191B CN 2009100625242 A CN2009100625242 A CN 2009100625242A CN 200910062524 A CN200910062524 A CN 200910062524A CN 101572191 B CN101572191 B CN 101572191B
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mesoporous carbon
ordered mesoporous
composite material
carbon composite
carbon carrier
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CN101572191A (en
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陈文�
赵春霞
喻理
龙曦
宋彦宝
冯素波
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Wuhan University of Technology WUT
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Abstract

The invention discloses a V2O5-ordered mesoporous carbon composite material and a preparation method thereof. The V2O5-ordered mesoporous carbon composite material has a mesoporous structure. The V2O5 nano grain size is even, and the nano grains are evenly scattered in an ordered mesoporous carbon carrier. The size of the V2O5 grains is 4 nm or less. The ratio of the ordered mesoporous carbon carrier to the V2O5 nano grains is 1:0.08-0.25. The method comprises the following steps: firstly, carrying out hydrophilic treatment for the ordered mesoporous carbon carrier, and then evenly scattering vanadium oxide precursor liquid into pore canals of the mesoporous carbon carrier under ultrasonic condition; and filtering and washing the mesoporous carbon carrier, and drying the mesoporous carbon carrier in vacuum at 120 DEG C to form the V2O5-ordered mesoporous carbon composite material. The cyclic voltammetry and constant current charge-discharge research in a three-electrode system shows that the prepared V2O5-ordered mesoporous carbon composite material has larger discharge specific capacitance and good stability. The method has the advantages of simple process and low requirement on equipment, can be realized under normal temperature, and has strong operability. Therefore, the composite material and the method can be widely applied to the aspects of electrode materials.

Description

A kind of V 2O 5-ordered mesoporous carbon composite material and preparation method thereof
Technical field
The invention belongs to nano material and field of nanometer technology, be specifically related to a kind of through the synthetic V of ultrasonic auxiliary liquid phase method 2O 5The new method of-ordered mesoporous carbon composite material.
Background technology
Ultracapacitor is the novel energy-storing device between ordinary capacitor and secondary cell, has both the high and high advantage of secondary cell energy density of ordinary capacitor power density, is the new green power of paying close attention to both at home and abroad in recent years.Usually; Electrochemical capacitor can be divided into two kinds by energy storage mechanism: a kind of electrode/electrolyte interface charge that is based on is separated the electric double layer capacitance that is produced, and a kind of in addition is to utilize the surface of electrode and the middle mutually quick reversible redox reaction that takes place of body to form Faraday pseudo-capacitance.
At present, double layer capacitor is used absorbent charcoal material, and needs employing activation engineering increases its specific area usually, and the specific area practical efficiency of this type of material with carbon element is merely about 10%; In addition, it has higher resistance, has limited the application of double layer capacitor.Metal oxide is like RuO x, IrO x, TaO xDeng performance with fake capacitance, though have bigger than electric capacity, energy density is high and characteristics that can fast charging and discharging, the specific area of metal oxide is less, unstable properties, and its high price has limited their commercialization.Therefore, need be with double layer capacitor and the combination of fake capacitance device, in the hope of realizing the rational and balanced between material cost and the performance.
Vanadium is one of typical polyvalent metal element, can form multiple oxide, like VO 2, V 2O 5, V 6O 13Deng.As far back as 1976, people were just to V 2O 5Study as anode material for lithium-ion batteries, but its research as electrode material for super capacitor is just come into one's own in recent years.Jiang etc. pass through the chemical gaseous phase injection method with RuO 2XH 2O and mesoporous carbon are compound, and it is than the single porous carbon materials of capacity ratio be significantly increased (J.Power Sources 2003,123,79).But the problem that metal oxide particle is assembled appears in traditional infusion process easily.In addition, V 2O 5Fusing point lower and active higher, high-temperature process such as chemical gaseous phase injection are easy to cause structure to cave in and phase transition.Thereby select meso-porous carbon material as carrier, it is good, low-cost and preparation method that oxide can be evenly distributed in the carrier is significant to study a kind of controllability.
Summary of the invention
The object of the invention aims to provide a kind of V 2O 5-ordered mesoporous carbon composite material, and provide a kind of implement effective, feasible, the preparation method of barium oxide-ordered mesoporous carbon composite material that mesoscopic structure remains intact.
Realize a kind of V of the object of the invention 2O 5-ordered mesoporous carbon composite material is characterized in that having mesoscopic structure, V 2O 5The nanoparticle size homogeneous, and be evenly dispersed in the phosphorus-ordered mesoporous carbon carrier V 2O 5Particle is of a size of 4nm or littler nano particle, phosphorus-ordered mesoporous carbon carrier and V 2O 5The mass fraction ratio of nano particle is 1: 0.08-0.25.
A kind of V of the present invention 2O 5The preparation method of-ordered mesoporous carbon composite material; Be characterized in utilizing ultrasonic auxiliary liquid phase synthesizing method, the steps include: at room temperature, phosphorus-ordered mesoporous carbon carrier material and barium oxide predecessor are mixed stirring; Under ultrasound condition, handle 1-3h then; Filter, it is colourless to filtrating to spend deionised water, obtains the pitchy product; The pitchy product that obtains at 120 ℃ of vacuum drying 24h, is promptly obtained V 2O 5-ordered mesoporous carbon composite material, V 2O 5Nano particle is evenly dispersed in the phosphorus-ordered mesoporous carbon carrier, and wherein, described barium oxide predecessor is V 2O 5Colloidal sol, concentration are 0.01-0.08mol/L; Phosphorus-ordered mesoporous carbon carrier and V 2O 5Colloidal sol is pressed mass ratio 1: 50-150 and is mixed.
In the method for the present invention, the self-control ordered mesoporous carbon material CMK-3 that described phosphorus-ordered mesoporous carbon carrier material is a hydrophilic treatment ( embodiment 5,6 is seen in its preparation); Described ultrasonic power is 100kHz.
This method has solved supported V in the mesoporous carbon carrier 2O 5The problem of nano particle difficulty in the duct of barium oxide predecessor through ultrasonic auxiliary entering phosphorus-ordered mesoporous carbon carrier, and is uniformly dispersed, and the duct keeps complete relatively in order, has obtained V 2O 5The equally distributed V of nano particle 2O 5-ordered mesoporous carbon composite material.Its V 2O 5Particle is of a size of 4nm or littler nano particle.
The surface hydrophilic functionalization method of ordered mesopore carbon: with ordered mesopore carbon CMK-3 and 20wt%HNO 3Mix, mixed liquor is moved in the inner liner of reaction kettle of polytetrafluoroethylene (PTFE) hydro-thermal reaction 3h in 80 ℃ of baking ovens.Naturally cooling is filtered, and spends deionised water to neutral, and 80 ℃ of oven dryings finally obtain the ordered mesopore carbon CMK-3 carrier of hydrophile function processing.
V of the present invention 2O 5-ordered mesoporous carbon composite material is particularly suitable for as capacitor electrode material.
The present invention is through introducing object oxide V in the phosphorus-ordered mesoporous carbon carrier material 2O 5, form a kind of special construction, be intended to utilize effective proportioning of the super large specific energy and the electric double layer capacitance of metal oxide, by electric double layer capacitance and Faraday pseudo-capacitance acting in conjunction, obtain high specific energy.Preparation technology of the present invention is simple, and is low for equipment requirements, and operability is good, and greatly reduces cost; Especially for the metal oxide of this type of barium oxide low melting point, multivalence attitude, just can realize that under lower temperature it is compound, structural deterioration and the variation of valence of having avoided high-temperature process to cause.
The V of the present invention's preparation 2O 5-ordered mesoporous carbon composite material shows in the cyclic voltammetry and the constant current charge-discharge research of three-electrode system, compares V with only using ordered mesopore carbon as electrode 2O 5The capacitive property of-ordered mesoporous carbon composite material electrode obviously improves, and stability better.
Description of drawings
Fig. 1 is the low angle XRD figure spectrum of embodiment 1 product
Fig. 2 is the wide-angle XRD figure spectrum of embodiment 1 product
Fig. 3 is the V 2p xps energy spectrum of embodiment 1 product
Fig. 4 is the TEM image of embodiment 1 product
Fig. 5 is the TEM image of CMK-3
Fig. 6 is the characteristic nitrogen adsorption-desorption isotherm of embodiment 1 product
Fig. 7 is the graph of pore diameter distribution of embodiment 1 product
Fig. 8 be embodiment 1 product as electrode at 1mol/L KNO 3Cyclic voltammetry curve in the solution
V shown in Figure 1 2O 5(100) face of the corresponding two-dimentional hexagonal structure in position of the diffraction maximum of the low angle XRD figure spectrum of-ordered mesoporous carbon composite material; With bibliographical information (Ryoo etc.; J.Am.Chem.Soc.2000; The low angle XRD figure spectrum of ordered mesoporous material 122,10712) matches, and shows that product has orderly meso-hole structure.
V shown in Figure 2 2O 5The corresponding orthohormbic structure V in position of the diffraction maximum of the wide-angle XRD figure spectrum of-ordered mesoporous carbon composite material 2O 5(101) and (002) peak, show that barium oxide in the composite is with V 2O 5Form exist; The intensity of diffraction maximum a little less than, show that the barium oxide particle size is less, degree of crystallinity is not high.
V shown in Figure 3 2O 5The V 2p xps energy spectrum of-ordered mesoporous carbon composite material confirms that further barium oxide is V 2O 5
Fig. 4 explains V 2O 5Nano particle is evenly dispersed in the phosphorus-ordered mesoporous carbon carrier, V 2O 5The size of nano particle is about 4nm.
Fig. 5 explains that phosphorus-ordered mesoporous carbon carrier CMK-3 has that rule is arranged, the pore passage structure of size homogeneous.
Fig. 6 explains that product has the suction dissolubility indicatrix of typical mesoporous material.
Fig. 7 explains the narrow pore size distribution range of product.
Fig. 8 explains that the fake capacitance characteristic of product is comparatively obvious, is illustrated in the potential window scope, and faraday's reaction has taken place for product and electrolyte, is wherein comprising a plurality of oxidation-reduction pairs continuous, reversible conversion.
The specific embodiment
V of the present invention 2O 5The preparation method of-ordered mesoporous carbon composite material; Be to utilize ultrasonic auxiliary liquid phase synthesizing method, the steps include: at room temperature, phosphorus-ordered mesoporous carbon carrier material and barium oxide predecessor are mixed stirring; Under ultrasound condition, handle 1-3h then; Filter, it is colourless to filtrating to spend deionised water, obtains the pitchy product; The pitchy product that obtains at 120 ℃ of vacuum drying 24h, is promptly obtained V 2O 5-ordered mesoporous carbon composite material, wherein, described barium oxide predecessor is V 2O 5Colloidal sol, concentration are 0.01-0.08mol/L; Phosphorus-ordered mesoporous carbon carrier and V 2O 5Colloidal sol is pressed mass ratio 1: 50-150 and is mixed.
Embodiment 1
V 2O 5An embodiment preferred among the preparation method of-ordered mesoporous carbon composite material comprises the steps: V 2O 5Be 0.06mol/L V 2O 5Colloidal sol, phosphorus-ordered mesoporous carbon carrier are the CMK-3 of hydrophile function processing.At room temperature, 0.2g CMK-3 is joined 20g V 2O 5In the colloidal sol, stirring 3h, is sonicated 3h under the 100kHz at power then, filter, and washing, 120 ℃ of vacuum drying 24h obtain V 2O 5-ordered mesoporous carbon composite material.The low angle XRD figure spectrum of product is seen Fig. 1, and wide-angle XRD figure spectrum is seen Fig. 2, and V 2p xps energy spectrum is seen Fig. 3, TEM image such as Fig. 4, and characteristic nitrogen adsorption-desorption isotherm such as Fig. 6 of product, graph of pore diameter distribution is seen Fig. 7.
Embodiment 2
V 2O 5The preparation of-ordered mesoporous carbon composite material: V 2O 5Be 0.01mol/L V 2O 5Colloidal sol, phosphorus-ordered mesoporous carbon carrier are the CMK-3 of hydrophile function processing.At room temperature, 0.2g CMK-3 is joined 10g V 2O 5In the colloidal sol, stirring 3h, is sonicated 1h under the 100kHz at power then, filter, and washing, 120 ℃ of vacuum drying 24h obtain V 2O 5-ordered mesoporous carbon composite material.
Embodiment 3
V 2O 5The preparation of-ordered mesoporous carbon composite material: V 2O 5Be 0.08mol/L V 2O 5Colloidal sol, phosphorus-ordered mesoporous carbon carrier are the CMK-3 of hydrophile function processing.At room temperature, 0.2g CMK-3 is joined 30g V 2O 5In the colloidal sol, stirring 3h, is sonicated 3h under the 100kHz at power then, filter, and washing, 120 ℃ of vacuum drying 24h obtain V 2O 5-ordered mesoporous carbon composite material.
Embodiment 4
V 2O 5Synthesizing of colloidal sol: with 0.545g V 2O 5With 50mL H 2O 2Join in the 100mL round-bottomed flask, whole system remains on strong magnetic agitation in the ice bath, has become a kind of bright orange solution (system pH=1.5) behind about 20min, and behind the 24h, system changes generation rufous colloidal sol gradually, is V 2O 5Colloidal sol.The V of the configurable variable concentrations of this method 2O 5Colloidal sol.Used in the instance 1 is the V of 0.06mol/L 2O 5Colloidal sol.
Embodiment 5
Ordered mesopore carbon CMK-3's is synthetic: 1g mesopore silicon oxide SBA-15 joins in the vitriolated aqueous sucrose solution (pressing 1.25g sucrose, 0.2g sulfuric acid and the preparation of 5g water), stirs.Mixture is placed in the drying box, 50 ℃ of insulation 12h, and subsequently, temperature rises to 160 ℃ of insulation 6h.Increase 0.75g sucrose, 0.1g sulfuric acid and 5g water take place to stir in the partially polymerized silica sample to sucrose, under 50 ℃ and 160 ℃, in drying box, carry out same treatment.Speed with 250 ℃/h rises to 900 ℃ of insulation 6h under nitrogen protection atmosphere then, accomplishes whole carbonisation.Gained silicon/carbon dioxide combination product is removed template with the HF acid solution dipping of 8wt%.End product is through filtering, and deionized water is washed till neutrality, and 100 ℃ of dryings obtain ordered mesopore carbon CMK-3, and its TEM image is seen Fig. 5.The preparation of mesopore silicon oxide SBA-15 is referring to document (D.Y.Zhao etc., Science 1998,279,548).
Embodiment 6
The surface hydrophilic functionalization of ordered mesopore carbon: with the ordered mesopore carbon CMK-3 and the 20wt%HNO of embodiment 5 preparations 3Mix, mixed liquor is moved in the inner liner of reaction kettle of polytetrafluoroethylene (PTFE) hydro-thermal reaction 3h in 80 ℃ of baking ovens.Naturally cooling is filtered, and spends deionised water to neutral, and 80 ℃ of oven dryings finally obtain the phosphorus-ordered mesoporous carbon carrier of hydrophile function processing.
Embodiment 7
The preparation of electrode: the mass ratio by 90: 10 takes by weighing V 2O 5The polytetrafluoroethylene (PTFE) emulsion of-ordered mesoporous carbon composite material and 12wt% is mixed appearance with an amount of isopropyl alcohol, after mixing, and infrared lamp oven dry down.The oven dry sample is pressed on the nickel foam under the pressure of 10MPa, for use in 80 ℃ of vacuum drying 24h.The surface area of the electrode slice of making is 1cm2.
Embodiment 8
Cyclic voltammetric test: be prepared into working electrode according to embodiment 7 with the foregoing description 1 product; Saturated calomel electrode is as reference electrode; Platinum electrode is formed the standard three-electrode system as to electrode, on Autolab PGATAT30 type electrochemical workstation, carries out the cyclic voltammetric test.Fig. 8 is presented at the KNO of 1mol/L 3In the electrolyte, voltage scan range 0-0.8V, sweep speed is the following 20 times cyclic voltammetry curve of 5mV/s condition.
Embodiment 9
The constant current charge-discharge test: the constant current charge-discharge test is tested on Autolab PGATAT30 type electrochemical workstation; Be prepared into working electrode with the foregoing description 1 product according to embodiment 7; Saturated calomel electrode is as reference electrode, and platinum electrode is formed the standard three-electrode system as to electrode.When current density is got 0.2A/g, potential region 0-0.8V, discharge is 124F/g than electric capacity.

Claims (4)

1. V 2O 5-ordered mesoporous carbon composite material is characterized in that having mesoscopic structure, V 2O 5The nanoparticle size homogeneous, and be evenly dispersed in the phosphorus-ordered mesoporous carbon carrier V 2O 5Particle is of a size of 4nm or littler nano particle, phosphorus-ordered mesoporous carbon carrier and V 2O 5The mass fraction ratio of nano particle is 1: 0.08-0.25.
2. V 2O 5The preparation method of-ordered mesoporous carbon composite material; It is characterized in that utilizing ultrasonic auxiliary liquid phase synthesizing method, the steps include: at room temperature, phosphorus-ordered mesoporous carbon carrier material and barium oxide predecessor are mixed stirring; Under ultrasound condition, handle 1-3h then; Filter, it is colourless to filtrating to spend deionised water, obtains the pitchy product; The pitchy product that obtains at 120 ℃ of vacuum drying 24h, is promptly obtained V 2O 5-ordered mesoporous carbon composite material, V 2O 5Nano particle is evenly dispersed in the phosphorus-ordered mesoporous carbon carrier, and wherein, described barium oxide predecessor is V 2O 5Colloidal sol, concentration are 0.01-0.08mol/L; Phosphorus-ordered mesoporous carbon carrier and V 2O 5Colloidal sol is pressed mass ratio 1: 50-150 and is mixed.
3. V according to claim 2 2O 5The preparation method of-ordered mesoporous carbon composite material is characterized in that: ultrasonic power is 100kHz.
4. the described V of claim 1 2O 5The application of-ordered mesoporous carbon composite material is characterized in that: as capacitor electrode material.
CN2009100625242A 2009-06-05 2009-06-05 V2O5-ordered mesoporous carbon composite material and preparation method thereof Expired - Fee Related CN101572191B (en)

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CN101834006B (en) * 2010-04-27 2011-06-08 武汉理工大学 MoO3 and ordered mesoporous carbon composite electrode material and preparation method thereof
CN102631914A (en) * 2011-02-15 2012-08-15 中国石油化工股份有限公司 Vanadium pentoxide catalyst taking mesoporous carbon as carrier, and preparation method thereof
CN103258653B (en) * 2013-04-15 2015-12-02 武汉理工大学 There is the barium oxide and carbon composite and preparation method thereof of hierarchical porous structure
CN110391401A (en) * 2019-06-25 2019-10-29 肇庆理士电源技术有限公司 OMC based combined electrode and lead-acid battery
CN111584247B (en) * 2020-05-20 2021-11-05 重庆普朗电气设备有限公司 V-shaped groove2O5Nitrogen-sulfur-loaded double-doped porous carbon supercapacitor electrode material and preparation method thereof
CN112233910B (en) * 2020-10-19 2022-11-01 成都先进金属材料产业技术研究院股份有限公司 Preparation method of nano vanadium dioxide/natural porous carbon electrode material

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