Titanium suboxide electrode material, and preparation method and application thereof

Abstract

The application relates to the technical field of wastewater treatment, and discloses a titanium suboxide electrode material as well as a preparation method and application thereof. The titanium suboxide electrode material comprises, from top to bottom, a modified graphene oxide layer, a titanium suboxide layer and a modified iron-based metal organic framework material layer. The titanium suboxide electrode material provided by the application has a COD removal rate of 96.14% in wastewater, and has a good removal effect on COD in the wastewater.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wastewater treatment, in particular to a titanium sub-oxide electrode material and a preparation method and application thereof. BACKGROUND

[0002] Chemical oxygen demand (COD) as a key indicator to measure the content of organic pollutants in wastewater, its effective removal is of great significance to wastewater discharge and environmental protection. At present, the common COD removal methods include physical method, chemical method and biological method. Physical methods such as sedimentation and filtration can only remove suspended particles and part of colloidal substances in wastewater, and the removal effect of dissolved organic pollutants is poor, which cannot meet the demand of advanced treatment. In chemical method, although Fenton oxidation method has strong oxidation ability, a large amount of chemical agents need to be added, which has high cost and is easy to cause secondary pollution; ozone oxidation method has large equipment investment and high operation cost, and the utilization rate of ozone is low. Although biological method has the advantages of low cost and environmental friendliness, the treatment efficiency is relatively low, and the water quality and environmental conditions are harsh, such as poor biodegradability of wastewater, large water quality fluctuation or containing toxic substances, the biological treatment effect will be significantly affected, and it is difficult to ensure stable COD removal rate.

[0003] With the rapid development of industry, the composition of wastewater is becoming more and more complex, which puts forward higher requirements for COD removal technology. Developing efficient, economical and environmentally friendly COD removal technology has become a research hotspot. Among many research directions, electrochemical advanced oxidation technology has attracted widespread attention due to its strong oxidation ability, fast reaction speed, no secondary pollution and simple operation.

[0004] The core of electrochemical advanced oxidation technology is anode material, and its performance directly affects the COD removal effect and energy consumption. Traditional anode materials such as graphite electrode have poor conductivity, low mechanical strength and short service life; although noble metal electrodes (such as platinum, ruthenium, etc.) have high catalytic activity, they are expensive, which limits their large-scale application; titanium-based metal oxide electrodes (such as Ti / RuO2, Ti / IrO2, etc.) have poor stability, easy deactivation and low oxygen evolution overpotential, which easily causes anode passivation in the treatment of high-concentration organic wastewater, resulting in a decrease in treatment efficiency. Therefore, it is an urgent technical problem for those skilled in the art to provide a titanium sub-oxide electrode material. SUMMARY

[0005] The purpose of the present application is to provide a titanium sub-oxide electrode material and a preparation method and application thereof.

[0006] To achieve the above purpose, the present application provides the following technical scheme:

[0007] One of the technical schemes of the present application is:

[0008] A titanium suboxide electrode material, which is composed of a modified graphene oxide layer, a titanium suboxide layer and a modified iron-based metal organic framework material layer from top to bottom.

[0009] Further, the preparation method of the modified graphene oxide comprises the following steps:

[0010] 1.1: dispersing graphene oxide in ethanol to obtain an ethanol dispersion of graphene oxide, and then adding iron chloride hexahydrate into the ethanol dispersion of graphene oxide and stirring to obtain iron ion bridged graphene oxide;

[0011] 1.2: immersing the iron ion bridged graphene oxide obtained in step 1.1 in a hydrogen iodide solution with a concentration of 1.15 g / mL;

[0012] 1.3: immersing the iron ion bridged graphene oxide after the immersion treatment in step 1.2 in an acid solution for modification to obtain the modified graphene oxide.

[0013] The preparation method of the titanium suboxide comprises the following steps:

[0014] mixing titanium dioxide and titanium, keeping in air atmosphere, then calcining in nitrogen atmosphere, cooling and ball milling to obtain titanium suboxide powder with an average particle size of 35 μm, i.e. the titanium suboxide;

[0015] The preparation method of the modified iron-based metal organic framework material comprises the following steps:

[0016] 2.1: dissolving diaminoterephthalic acid and iron chloride hexahydrate in N,N-dimethylformamide and reacting to obtain an iron-based metal organic framework material;

[0017] 2.2: dispersing the iron-based metal organic framework material obtained in step 2.1 in ethanol to obtain an ethanol dispersion of the iron-based metal organic framework material, and then adding transition metal oxide into the ethanol dispersion of the iron-based metal organic framework material and ultrasonic dispersing to obtain the modified iron-based metal organic framework material.

[0018] Further, in step 1.1, the mass ratio of the graphene oxide to the iron chloride hexahydrate is 10: (1-3).

[0019] Further, in step 1.1, the stirring specifically is: controlling the stirring speed to be 40 r / min and stirring at 120-160 ℃ for 4-8 h.

[0020] Further, in step 1.2, the mass-volume ratio of the iron ion bridged graphene oxide to the hydrogen iodide solution is 1 g: 5 mL.

[0021] Further, in step 1.2, the dipping treatment is specifically: dipping treatment at room temperature for 5-15 min.

[0022] Further, in step 1.3, the acid solution is a sulfuric acid solution with a concentration of 1 mol / L or a nitric acid solution with a concentration of 1 mol / L.

[0023] Further, in step 1.3, the dipping modification is specifically: dipping modification at 40-60℃ for 2-3h.

[0024] Further, the mass ratio of titanium dioxide and titanium is (1-3):1.

[0025] Further, the heat preservation is specifically: heat preservation at 1600-1650℃ for 20-40 min.

[0026] Further, the calcination is specifically: calcination at 1350-1450℃ for 8-10h.

[0027] Further, in step 2.1, the mass ratio of diaminoterephthalic acid and ferric chloride hexahydrate is 1: (1.5-2).

[0028] Further, in step 2.1, the reaction is specifically: reaction at 140-160℃ for 24-36h.

[0029] Further, in step 2.2, the transition metal oxide is one or more of nickel oxide, manganese dioxide and tricobalt tetroxide.

[0030] Further, in step 2.2, the mass ratio of the iron-based metal-organic framework material and the transition metal oxide is 10: (0.5-1.5).

[0031] The second technical scheme of the present application:

[0032] The preparation method of the above-mentioned titanium suboxide electrode material comprises the following steps:

[0033] 1) According to the layer structure of the modified graphene oxide layer, the titanium suboxide layer and the modified iron-based metal-organic framework material layer, the modified graphene oxide, the titanium suboxide and the modified iron-based metal-organic framework material are placed in a graphite mold for preforming to obtain a preformed titanium suboxide electrode material.

[0034] 2) The preformed titanium suboxide electrode material obtained in step 1) is subjected to spark plasma sintering to obtain the titanium suboxide electrode material.

[0035] Further, in step 2), the pressure of the spark plasma sintering is 10-100 MPa, the temperature is 1000-1300℃, and the time length is 5-15 min.

[0036] The third aspect of the present application is:

[0037] Application of the above-mentioned titanium suboxide electrode material in removal of COD in wastewater.

[0038] Compared with the prior art, the present application has the beneficial effects that:

[0039] The titanium suboxide electrode material provided by the present application has a COD removal rate of 96.14% in wastewater, and has a good removal effect on COD in wastewater. DETAILED DESCRIPTION

[0040] The various exemplary embodiments of the present application will now be described in detail, which should not be considered as limiting the present application, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present application. It should be understood that the terms described in the present application are only for the description of the particular embodiments, and are not used to limit the present application.

[0041] In addition, for the numerical range in the present application, it should be understood that each intermediate value between the upper limit and the lower limit of the range is also specifically disclosed. Each smaller range between any stated value or intermediate value in the stated range and any other stated value or intermediate value in the stated range is also included in the present application. The upper limit and the lower limit of these smaller ranges can be independently included or excluded from the range.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application pertains. Although preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are concerned. In the event of any conflict between the content of this specification and the documents incorporated by reference, the content of this specification shall prevail.

[0043] Many modifications and variations of the present application specification can be made without departing from the scope or spirit of the present application, which will be apparent to those skilled in the art. Other embodiments resulting from the present application specification will be apparent to those skilled in the art. The present application specification and examples are only exemplary.

[0044] As used herein, "comprise", "include", "have", "contain", and the like, are open-ended terms, i.e., meaning "including but not limited to".

[0045] In the following examples, a method for preparing a titanium suboxide electrode material includes the following steps:

[0046] 1. Preparation of modified graphene oxide

[0047] 1.1 Disperse graphene oxide in ethanol to obtain an ethanol dispersion of graphene oxide, then add ferric chloride hexahydrate to the ethanol dispersion of graphene oxide according to a mass ratio of graphene oxide to ferric chloride hexahydrate of 10:(1-3), control the stirring speed at 40 r / min, and stir at 120-160°C for 4-8 h, centrifuge, wash with water, and dry to obtain iron ion bridged graphene oxide;

[0048] 1.2 Place the iron ion bridged graphene oxide obtained in step 1) in a hydrogen iodide solution with a concentration of 1.15 g / mL, and immerse and treat at room temperature for 5-15 min according to a mass-volume ratio of iron ion bridged graphene oxide to hydrogen iodide solution of 1 g:5 mL;

[0049] 1.3 Place the iron ion bridged graphene oxide after the immersion and treatment in step 1.2 in an acidic solution, immerse and modify at 40-60°C for 2-3 h to obtain the modified graphene oxide;

[0050] The acidic solution is a sulfuric acid solution with a concentration of 1 mol / L or a nitric acid solution with a concentration of 1 mol / L;

[0051] 2. Preparation of titanium suboxide

[0052] Mix titanium dioxide and titanium according to a mass ratio of titanium dioxide to titanium of (1-3):1, heat at 1600-1650°C for 20-40 min in an air atmosphere, then calcine at 1350-1450°C for 8-10 h in a nitrogen atmosphere, cool, and ball mill to obtain titanium suboxide powder with an average particle size of 35 μm, i.e., the titanium suboxide;

[0053] 3. Preparation of modified iron-based metal organic framework material

[0054] 2.1 Dissolve diamino terephthalic acid and ferric chloride hexahydrate in N,N-dimethylformamide according to a mass ratio of diamino terephthalic acid to ferric chloride hexahydrate of 1:(1.5-2), and react at 140-160°C for 24-36 h, centrifuge, wash with water, and dry to obtain an iron-based metal organic framework material;

[0055] 2.2 Disperse the iron-based metal organic framework material obtained in step 1.1 in ethanol to obtain an ethanol dispersion of the iron-based metal organic framework material, then add a transition metal oxide to the ethanol dispersion of the iron-based metal organic framework material according to a mass ratio of the iron-based metal organic framework material to the transition metal oxide of 10:(0.5-1.5), ultrasonically disperse at 60-80°C for 30 min, centrifuge, wash with water, and dry to obtain the modified iron-based metal organic framework material;

[0056] wherein the transition metal oxide is one or more of nickel oxide, manganese dioxide, and tricobalt tetroxide;

[0057] 4. Preparation of titanium suboxide electrode material

[0058] 1) According to the layer structure of the modified graphene oxide layer, the titanium suboxide layer, and the modified iron-based metal organic framework material layer, the modified graphene oxide prepared in step 1, the titanium suboxide prepared in step 2, and the modified iron-based metal organic framework material prepared in step 3 are placed in a graphite mold, and preformed under a pressure of 20 MPa to obtain a preformed titanium suboxide electrode material;

[0059] 2) The preformed titanium suboxide electrode material obtained in step 1 is subjected to spark plasma sintering in a nitrogen atmosphere to obtain the titanium suboxide electrode material;

[0060] wherein the pressure of the spark plasma sintering is 10-100 MPa, the temperature is 1000-1300 °C, and the time length is 5-15 min.

[0061] Example 1

[0062] Titanium suboxide electrode material

[0063] 1. Preparation of modified graphene oxide

[0064] 1) Graphene oxide is dispersed in ethanol to obtain an ethanol dispersion of graphene oxide, and then according to a mass ratio of graphene oxide to ferric chloride hexahydrate of 10:1, ferric chloride hexahydrate is added to the ethanol dispersion of graphene oxide, the stirring speed is controlled at 40 r / min, stirring is carried out at 120 °C for 4 h, centrifugation, water washing, and drying are carried out to obtain iron ion bridged graphene oxide;

[0065] 2) According to a mass-volume ratio of iron ion bridged graphene oxide to hydrogen iodide solution of 1 g:5 mL, the iron ion bridged graphene oxide obtained in step 1 is placed in a hydrogen iodide solution with a concentration of 1.15 g / mL, and immersed at room temperature for 5 min to reduce the interaction force between adjacent graphene oxide nanosheets;

[0066] 3) The iron ion bridged graphene oxide after immersion treatment in step 2 is placed in an acidic solution and immersed at 40 °C for 2 h to obtain the modified graphene oxide;

[0067] wherein the acidic solution is a sulfuric acid solution with a concentration of 1 mol / L;

[0068] 2. Preparation of titanium suboxide

[0069] The titanium suboxide powder with an average particle size of 35 μm, i.e., the titanium suboxide, is obtained by mixing titanium dioxide and titanium according to a mass ratio of 1:1, heat treating at 1600°C for 20 min in an air atmosphere, then calcining at 1350°C for 8 h in a nitrogen atmosphere, cooling, and ball milling;

[0070] 3. Preparation of modified iron metal organic framework material

[0071] 1) Dissolve diamino terephthalic acid and ferric chloride hexahydrate in N,N-dimethylformamide according to a mass ratio of 1:1.5, react at 140°C for 24 h, centrifuge, wash with water, and dry to obtain the iron metal organic framework material;

[0072] 2) Disperse the iron metal organic framework material obtained in step 1) in ethanol to obtain an ethanol dispersion of the iron metal organic framework material, then add a transition metal oxide to the ethanol dispersion of the iron metal organic framework material according to a mass ratio of 10:0.5, ultrasonically disperse at 60°C for 30 min, centrifuge, wash with water, and dry to obtain the modified iron metal organic framework material;

[0073] The transition metal oxide is nickel oxide;

[0074] 4. Preparation of titanium suboxide electrode material

[0075] 1) Place the modified graphene oxide prepared in step 1, the titanium suboxide prepared in step 2, and the modified iron metal organic framework material prepared in step 3 in a graphite mold according to the layer structure of a modified graphene oxide layer, a titanium suboxide layer, and a modified iron metal organic framework material layer, pre-form under a pressure of 20 MPa to obtain a pre-formed titanium suboxide electrode material;

[0076] 2) Perform spark plasma sintering on the pre-formed titanium suboxide electrode material obtained in step 1) in a nitrogen atmosphere to obtain the titanium suboxide electrode material;

[0077] The pressure of the spark plasma sintering is 10 MPa, the temperature is 1000°C, and the time length is 5 min.

[0078] Example 2

[0079] A titanium suboxide electrode material

[0080] 1. Preparation of modified graphene oxide

[0081] 1) graphene oxide is dispersed in ethanol to obtain an ethanol dispersion of graphene oxide, and then ferric chloride hexahydrate is added to the ethanol dispersion of graphene oxide according to a mass ratio of graphene oxide to ferric chloride hexahydrate of 10:2, the stirring speed is controlled at 40 r / min, stirring is performed at 140°C for 6h, centrifugation, water washing, and drying are performed to obtain iron ion bridged graphene oxide;

[0082] 2) the iron ion bridged graphene oxide obtained in step 1) is placed in a hydrogen iodide solution with a concentration of 1.15 g / mL, and is immersed and treated at room temperature for 10 min to reduce the interaction force between adjacent graphene oxide nanosheets;

[0083] 3) the iron ion bridged graphene oxide after the immersion treatment in step 2) is placed in an acidic solution and is immersed and modified at 50°C for 2.5h to obtain the modified graphene oxide;

[0084] The acidic solution is a sulfuric acid solution with a concentration of 1 mol / L;

[0085] 2, Preparation of titanium suboxide

[0086] Titanium dioxide and titanium are mixed according to a mass ratio of titanium dioxide to titanium of 2:1, are kept at 1625°C for 30 min in an air atmosphere, are calcined at 1400°C for 9h in a nitrogen atmosphere, are cooled, and are ball milled to obtain titanium suboxide powder with an average particle size of 35 μm, i.e., the titanium suboxide;

[0087] 3, Preparation of modified iron-based metal organic framework material

[0088] 1) diamino terephthalic acid and ferric chloride hexahydrate are dissolved in N,N-dimethylformamide according to a mass ratio of diamino terephthalic acid to ferric chloride hexahydrate of 1:1.6, are reacted at 150°C for 30h, are centrifuged, are washed with water, and are dried to obtain an iron-based metal organic framework material;

[0089] 2) the iron-based metal organic framework material obtained in step 1) is dispersed in ethanol to obtain an ethanol dispersion of the iron-based metal organic framework material, and then a transition metal oxide is added to the ethanol dispersion of the iron-based metal organic framework material according to a mass ratio of the iron-based metal organic framework material to the transition metal oxide of 10:1, is ultrasonically dispersed at 70°C for 30 min, is centrifuged, is washed with water, and is dried to obtain the modified iron-based metal organic framework material;

[0090] The transition metal oxide is manganese dioxide;

[0091] 4, Preparation of titanium suboxide electrode material

[0092] 1) According to the layer structure of the modified graphene oxide layer, the titanium suboxide layer and the modified iron-based metal organic framework layer, the modified graphene oxide prepared in step 1, the titanium suboxide prepared in step 2 and the modified iron-based metal organic framework prepared in step 3 are placed in a graphite mold, preformed under a pressure of 20 MPa, to obtain a preformed titanium suboxide electrode material;

[0093] 2) The preformed titanium suboxide electrode material obtained in step 1 is subjected to spark plasma sintering in a nitrogen atmosphere, to obtain the titanium suboxide electrode material;

[0094] The pressure of the spark plasma sintering is 30 MPa, the temperature is 1150℃, and the time length is 10 min.

[0095] Example 3

[0096] A titanium suboxide electrode material

[0097] 1. Preparation of modified graphene oxide

[0098] 1) Graphene oxide is dispersed in ethanol to obtain an ethanol dispersion of graphene oxide, and then according to the mass ratio of graphene oxide to ferric chloride hexahydrate of 10:3, ferric chloride hexahydrate is added to the ethanol dispersion of graphene oxide, the stirring speed is controlled at 40 r / min, stirring reaction is carried out at 160℃ for 8h, centrifugation, water washing, drying, to obtain iron ion bridged graphene oxide;

[0099] 2) According to the mass-volume ratio of iron ion bridged graphene oxide to hydrogen iodide solution of 1g:5mL, the iron ion bridged graphene oxide obtained in step 1 is placed in a hydrogen iodide solution with a concentration of 1.15g / mL, and is immersed at room temperature for 15min to reduce the interaction force between adjacent graphene oxide nanosheets;

[0100] 3) The iron ion bridged graphene oxide after immersion treatment in step 2 is placed in an acidic solution and immersed in the acidic solution at 60℃ for 3h to obtain the modified graphene oxide;

[0101] The acidic solution is a nitric acid solution with a concentration of 1mol / L;

[0102] 2. Preparation of titanium suboxide

[0103] According to the mass ratio of titanium dioxide to titanium of 3:1, titanium dioxide and titanium are mixed, heated at 1650℃ for 40min in an air atmosphere, then calcined at 1450℃ for 10h in a nitrogen atmosphere, cooled, and ball milled to obtain titanium suboxide powder with an average particle size of 35μm, i.e. the titanium suboxide;

[0104] 3. Preparation of modified iron-based metal-organic framework material

[0105] 1) Dissolve diamino terephthalic acid and ferric chloride hexahydrate in N, N- dimethylformamide according to the mass ratio of diamino terephthalic acid to ferric chloride hexahydrate of 1:2, react at 160℃ for 36h, centrifuge, water wash, dry, and obtain the iron-based metal-organic framework material;

[0106] 2) Disperse the iron-based metal-organic framework material obtained in step 1) in ethanol to obtain an ethanol dispersion of the iron-based metal-organic framework material, and then add transition metal oxide into the ethanol dispersion of the iron-based metal-organic framework material according to the mass ratio of the iron-based metal-organic framework material to the transition metal oxide of 10:1.5, ultrasonic disperse at 80℃ for 30min, centrifuge, water wash, dry, and obtain the modified iron-based metal-organic framework material;

[0107] The transition metal oxide is cobalt oxide;

[0108] 4. Preparation of titanium suboxide electrode material

[0109] 1) According to the layer structure of modified graphene oxide layer, titanium suboxide layer and modified iron-based metal-organic framework material layer, place the modified graphene oxide prepared in step 1, the titanium suboxide prepared in step 2 and the modified iron-based metal-organic framework material prepared in step 3 in a graphite mold, pre-form under a pressure of 20MPa, and obtain the pre-formed titanium suboxide electrode material;

[0110] 2) Discharge plasma sinter the pre-formed titanium suboxide electrode material obtained in step 1 in a nitrogen atmosphere, and obtain the titanium suboxide electrode material;

[0111] The pressure of the discharge plasma sintering is 100MPa, the temperature is 1300℃, and the time length is 15min.

[0112] Example 4

[0113] A titanium suboxide electrode material

[0114] The same as example 2, except that in the preparation process of the modified iron-based metal-organic framework material in step 3, the transition metal oxide is a mixture of nickel oxide and manganese dioxide according to the mass ratio of 1:1.

[0115] Example 5

[0116] A titanium suboxide electrode material

[0117] The same as example 2, the only difference is that in the preparation process of modified iron-based metal organic framework material in step 3, the transition metal oxide is mixed by manganese dioxide and tricobalt tetroxide according to a mass ratio of 1:1.

[0118] Example 6

[0119] A titanium suboxide electrode material

[0120] The same as example 2, the only difference is that in the preparation process of modified iron-based metal organic framework material in step 3, the transition metal oxide is mixed by manganese dioxide and tricobalt tetroxide according to a mass ratio of 1:1.

[0121] Example 7

[0122] A titanium suboxide electrode material

[0123] The same as example 2, the only difference is that in the preparation process of modified iron-based metal organic framework material in step 3, the transition metal oxide is mixed by manganese dioxide and tricobalt tetroxide according to a mass ratio of 1:1.

[0124] Comparative example 1

[0125] A titanium suboxide electrode material

[0126] The same as example 6, the only difference is that in step 1, the preparation of modified graphene oxide is as follows:

[0127] 1) graphene oxide is dispersed in ethanol to obtain an ethanol dispersion of graphene oxide, and then according to a mass ratio of graphene oxide to ferric chloride hexahydrate of 10:2, ferric chloride hexahydrate is added to the ethanol dispersion of graphene oxide, the stirring speed is controlled at 40 r / min, and the stirring reaction is carried out at 140℃ for 6h, centrifugation, water washing, and drying to obtain iron ion bridged graphene oxide;

[0128] 2) the iron ion bridged graphene oxide obtained in step 1) is placed in an acid solution and modified by immersion at 50℃ for 2.5h to obtain the modified graphene oxide;

[0129] The acid solution is a sulfuric acid solution with a concentration of 1mol / L.

[0130] Comparative example 2

[0131] A titanium suboxide electrode material

[0132] The same as example 6, the only difference is that in step 1, the preparation of modified graphene oxide is as follows:

[0133] The graphene oxide is placed in an acid solution and modified by immersion at 50℃ for 2.5h to obtain the modified graphene oxide;

[0134] The acid solution is a sulfuric acid solution with a concentration of 1 mol / L.

[0135] Comparative Example 3

[0136] A titanium suboxide electrode material

[0137] The same as Example 6, except that the preparation of the modified graphene oxide in step 1 is as follows:

[0138] 1) The graphene oxide is dispersed in ethanol to obtain an ethanol dispersion of graphene oxide, and then ferric chloride hexahydrate is added to the ethanol dispersion of graphene oxide according to a mass ratio of graphene oxide to ferric chloride hexahydrate of 10:2, the stirring speed is controlled at 40 r / min, and the mixture is stirred at 140°C for 6 h, centrifuged, washed with water, and dried to obtain iron ion bridged graphene oxide.

[0139] 2) The iron ion bridged graphene oxide obtained in step 1 is placed in a hydrogen iodide solution with a concentration of 1.15 g / mL, and immersed at room temperature for 10 min according to a mass-volume ratio of iron ion bridged graphene oxide to hydrogen iodide solution of 1 g:5 mL to obtain the modified graphene oxide.

[0140] Comparative Example 4

[0141] A titanium suboxide electrode material

[0142] The same as Example 6, except that the preparation of the titanium suboxide in step 2 is as follows:

[0143] Titanium dioxide is calcined in an air atmosphere at 1625°C for 30 min, and then calcined in a nitrogen atmosphere at 1400°C for 9 h, cooled, and ball milled to obtain titanium suboxide powder with an average particle size of 35 μm, i.e., the titanium suboxide.

[0144] Comparative Example 5

[0145] A titanium suboxide electrode material

[0146] The same as Example 6, except that the preparation of the titanium suboxide in step 2 is as follows:

[0147] Titanium dioxide and titanium are mixed according to a mass ratio of titanium dioxide to titanium of 2:1, calcined in a nitrogen atmosphere at 1400°C for 9 h, cooled, and ball milled to obtain titanium suboxide powder with an average particle size of 35 μm, i.e., the titanium suboxide.

[0148] Comparative Example 6

[0149] A titanium suboxide electrode material

[0150] The difference from example 6 is that the modification of the iron-based metal organic framework material in step 3 is omitted, and in step 4, the preparation of the titanium suboxide electrode material is carried out with the iron-based metal organic framework material as a raw material.

[0151] Effect verification

[0152] The titanium suboxide electrode material is used as an anode, and graphite is used as a cathode, the current density is controlled to be 25 mA / cm 2 , the electrode spacing is 2.0 cm, 2.5 L of COD-containing wastewater is electrolyzed, the electrolysis time is controlled to be 2 h, the COD content in the wastewater after electrolysis is detected, and the COD removal rate is calculated; the detection results are shown in Table 1;

[0153] Table 1 Detection results

[0154]

[0155] It can be known from the data in Table 1 that the COD removal rate of the titanium suboxide electrode material provided by the application in wastewater can reach 96.14%, and the titanium suboxide electrode material has a good removal effect on COD in wastewater.

[0156] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application and not to limit it, although the present application has been described in detail with reference to the above examples, those skilled in the art should understand that: the specific embodiments of the present application can still be modified or replaced by the equivalent, without departing from the spirit and scope of the present application, any modification or equivalent replacement, which should be covered within the protection scope of the claims of the present application.

Claims

1. A titanium suboxide electrode material, characterized by, The titanium suboxide electrode material is composed of a modified graphene oxide layer, a titanium suboxide layer and a modified iron-based metal organic framework material layer from top to bottom. The preparation method of the modified graphene oxide comprises the following steps: 1.1: dispersing graphene oxide in ethanol to obtain an ethanol dispersion of graphene oxide, then adding iron chloride hexahydrate into the ethanol dispersion of graphene oxide, stirring and reacting to obtain iron ion bridged graphene oxide; 1.2: immersing the iron ion bridged graphene oxide obtained in step 1.1 in a hydrogen iodide solution with a concentration of 1.15 g / mL for immersion treatment; 1.3: immersing the iron ion bridged graphene oxide after the immersion treatment in step 1.2 in an acid solution for immersion modification to obtain the modified graphene oxide; The preparation method of the titanium suboxide comprises the following steps: mixing titanium dioxide and titanium, heat preservation in air atmosphere, then calcination in nitrogen atmosphere, cooling and ball milling to obtain titanium suboxide powder with an average particle size of 35 μm, i.e. the titanium suboxide; The preparation method of the modified iron-based metal organic framework material comprises the following steps: 2.1: dissolving diaminoterephthalic acid and iron chloride hexahydrate in N,N-dimethylformamide to obtain an iron-based metal organic framework material; 2.2: dispersing the iron-based metal organic framework material obtained in step 2.1 in ethanol to obtain an ethanol dispersion of the iron-based metal organic framework material, then adding transition metal oxide into the ethanol dispersion of the iron-based metal organic framework material for ultrasonic dispersion to obtain the modified iron-based metal organic framework material.

2. The titanium suboxide electrode material according to claim 1, wherein In step 1.1, the mass ratio of the graphene oxide and the iron chloride hexahydrate is 10:(1-3); the stirring and reaction is specifically as follows: the stirring speed is controlled at 40 r / min, and the stirring and reaction is carried out at 120-160 ℃ for 4-8 h; In step 1.2, the mass-volume ratio of the iron ion bridged graphene oxide and the hydrogen iodide solution is 1 g:5 mL; the immersion treatment is specifically as follows: the immersion treatment is carried out at room temperature for 5-15 min; In step 1.3, the acid solution is a sulfuric acid solution with a concentration of 1 mol / L or a nitric acid solution with a concentration of 1 mol / L; the immersion modification is specifically as follows: the immersion modification is carried out at 40-60 ℃ for 2-3 h.

3. The titanium suboxide electrode material of claim 1, wherein, The mass ratio of the titanium dioxide and the titanium is (1-3):1; the heat preservation is specifically as follows: the heat preservation is carried out at 1600-1650 ℃ for 20-40 min; the calcination is specifically as follows: the calcination is carried out at 1350-1450 ℃ for 8-10 h.

4. The titanium suboxide electrode material according to claim 1, wherein In step 2.1, the mass ratio of the diaminoterephthalic acid and the iron chloride hexahydrate is 1:(1.5-2); in step 2.1, the reaction is specifically as follows: the reaction is carried out at 140-160 ℃ for 24-36 h; In step 2.2, the transition metal oxide is one or more of nickel oxide, manganese dioxide and tricobalt tetroxide; and in step 2.2, the mass ratio of the iron-based metal-organic framework material and the transition metal oxide is 10: (0.5-1.5).

5. A method for producing the titanium suboxide electrode material according to any one of claims 1 to 4, characterized by, The method comprises the following steps: 3.1: according to the layer structure of the modified graphene oxide layer, the titanium suboxide layer and the modified iron-based metal-organic framework material layer, the modified graphene oxide, the titanium suboxide and the modified iron-based metal-organic framework material are placed in a graphite mold, preformed to obtain a preformed titanium suboxide electrode material; 3.2: the preformed titanium suboxide electrode material obtained in step 3.1 is subjected to spark plasma sintering to obtain the titanium suboxide electrode material.

6. The production method according to claim 5, characterized by, In step 3.2, the pressure of the spark plasma sintering is 10-100 MPa, the temperature is 1000-1300°C, and the time length is 5-15 min.

7. Use of the titanium suboxide electrode material according to any one of claims 1-4 in removal of COD in wastewater.

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