Preparation method for vanadium pentoxide/graphene composite positive electrode material of high-performance sodium ion battery

Abstract

The invention discloses a preparation method for a vanadium pentoxide / graphene composite positive electrode material of a high-performance sodium ion battery. The commercial vanadium pentoxide (V2O5)powder is used as a vanadium source, graphene aqueous dispersion liquid is used as a composite material, hydrogen peroxide (H2O2) is used as a cosolvent, and sol-sol is adopted. The preparation methodcomprises the following steps: preparing a V2O5*NH2O / graphene composite electrode material precursor by combining a sol-gel method with a vacuum freeze-drying technology, and then carrying out annealing treatment in air to obtain the V2O5*NH2O / graphene composite electrode material. The in-situ compounding method is adopted, so that graphene is uniformly distributed between V2O5*NH2O material layers. The method has the advantages that the sodium storage performance is good, the preparation method is simple, the cost is low, the yield is high, the reaction conditions are easy to control, and the like.

Description

technical field

[0001] The present invention relates to the technical field of sodium ion battery cathode material, be specifically related to a kind of high-performance vanadium pentoxide / graphene (V 2 o 5 ·nH 2 O / Graphene) preparation method of composite cathode material. Background technique

[0002] With the rapid development of renewable energy, electrochemical energy conversion storage technology is becoming more and more important. Metal sodium has abundant reserves, low price, and has similar physical and chemical properties to metal lithium. Therefore, sodium-ion batteries are considered to be the most potential substitutes for lithium-ion batteries. However Na + The radius is relatively large, the electrochemical reaction process is slow, and the electrochemical reaction process has great damage to the material, which seriously hinders the development of sodium-ion batteries. Therefore, the design and development of high-performance electrode materials is the k...

Examples

Embodiment 1

[0017] (1) First, 0.2547g of commercial vanadium pentoxide (V 2 o 5 ) powder and 3.85mL of deionized water were mixed and stirred in a water bath at room temperature for 5 minutes, and 1.15mL of 30% H 2 o 2 , continue to stir for 15 minutes after the dropwise addition is completed, then transfer it to an ultrasonic cleaner and add 20mL deionized water to dilute the solution to the concentration of vanadium pentoxide 0.056mol / L, continue to sonicate for 90 minutes to obtain a greenish-brown gel, leave it to age at room temperature for 3 days, and obtain a reddish-brown V 2 o 5 ·nH 2 O gel.

[0018] (2) The V obtained in step (1) 2 o 5 ·nH 2 O gel was stirred, dispersed, and diluted to the concentration of vanadium pentoxide with 25 mL of deionized water Continue to stir for 6 hours, then transfer the liquid to the refrigerator for freezing for 24 hours and then move to a freeze dryer to dry to constant weight and take out to obtain V 2 o 5 ·nH 2 O electrode materi...

Embodiment 2

[0021] (1) First, 0.2547g of commercial vanadium pentoxide (V 2 o 5 ) powder and 2.55mL mass percent concentration of 5% graphene (Graphene) aqueous dispersion in a water bath at normal temperature after mixing and stirring for 5 minutes, while stirring slowly added 1.15mL mass percent concentration of 30% H 2 o 2 , continue to stir for 15 minutes after the dropwise addition is completed, then transfer it to an ultrasonic cleaner and add 21.3mL deionized water to dilute the solution to the concentration of vanadium pentoxide was 0.056mol / L, continued ultrasonication for 90 minutes, and obtained a black gel, left to age at room temperature for 3 days, and obtained dark brown V 2 o 5 ·nH 2 O / Graphene Gel.

[0022] (2) The V obtained in step (1) 2 o 5 ·nH 2 The O / Graphene gel was stirred, dispersed, and diluted with 25 mL deionized water to Continue to stir for 6 hours, then transfer the liquid to the refrigerator for freezing for 24 hours and then move to a freeze dry...

Embodiment 3

[0025] (1) First, 0.2547g of commercial vanadium pentoxide (V 2 o 5 ) powder and 7.65mL mass percent concentration of 5% Graphene (Graphene) aqueous dispersion in a water bath at normal temperature after mixing and stirring for 5 minutes, while stirring, slowly dripping 1.15mL mass percent concentration of 30% H 2 o2 , continue to stir for 15 minutes after the dropwise addition is completed, then transfer it to an ultrasonic cleaner and add 16.2mL deionized water to dilute the solution to the concentration of vanadium pentoxide was 0.056mol / L, continued ultrasonication for 90 minutes, and obtained a black gel, left to age at room temperature for 3 days, and obtained dark brown V 2 o 5 ·nH 2 O / Graphene Gel.

[0026] (2) The V obtained in step (1) 2 o 5 ·nH 2 The O / Graphene gel was stirred, dispersed, and diluted with 25 mL deionized water to Continue to stir for 6 hours, then transfer the liquid to the refrigerator for freezing for 24 hours and then move to a freeze d...

technical field

[0001] The present invention relates to the technical field of sodium ion battery cathode material, be specifically related to a kind of high-performance vanadium pentoxide / graphene (V 2 o 5 ·nH 2 O / Graphene) preparation method of composite cathode material. Background technique

[0002] With the rapid development of renewable energy, electrochemical energy conversion storage technology is becoming more and more important. Metal sodium has abundant reserves, low price, and has similar physical and chemical properties to metal lithium. Therefore, sodium-ion batteries are considered to be the most potential substitutes for lithium-ion batteries. However Na + The radius is relatively large, the electrochemical reaction process is slow, and the electrochemical reaction process has great damage to the material, which seriously hinders the development of sodium-ion batteries. Therefore, the design and development of high-performance electrode materials is the k...

Examples

Embodiment 1

[0017] (1) First, 0.2547g of commercial vanadium pentoxide (V 2 o 5 ) powder and 3.85mL of deionized water were mixed and stirred in a water bath at room temperature for 5 minutes, and 1.15mL of 30% H 2 o 2 , continue to stir for 15 minutes after the dropwise addition is completed, then transfer it to an ultrasonic cleaner and add 20mL deionized water to dilute the solution to the concentration of vanadium pentoxide 0.056mol / L, continue to sonicate for 90 minutes to obtain a greenish-brown gel, leave it to age at room temperature for 3 days, and obtain a reddish-brown V 2 o 5 ·nH 2 O gel.

[0018] (2) The V obtained in step (1) 2 o 5 ·nH 2 O gel was stirred, dispersed, and diluted to the concentration of vanadium pentoxide with 25 mL of deionized water Continue to stir for 6 hours, then transfer the liquid to the refrigerator for freezing for 24 hours and then move to a freeze dryer to dry to constant weight and take out to obtain V 2 o 5 ·nH 2 O electrode materi...

Embodiment 2

[0021] (1) First, 0.2547g of commercial vanadium pentoxide (V 2 o 5 ) powder and 2.55mL mass percent concentration of 5% graphene (Graphene) aqueous dispersion in a water bath at normal temperature after mixing and stirring for 5 minutes, while stirring slowly added 1.15mL mass percent concentration of 30% H 2 o 2 , continue to stir for 15 minutes after the dropwise addition is completed, then transfer it to an ultrasonic cleaner and add 21.3mL deionized water to dilute the solution to the concentration of vanadium pentoxide was 0.056mol / L, continued ultrasonication for 90 minutes, and obtained a black gel, left to age at room temperature for 3 days, and obtained dark brown V 2 o 5 ·nH 2 O / Graphene Gel.

[0022] (2) The V obtained in step (1) 2 o 5 ·nH 2 The O / Graphene gel was stirred, dispersed, and diluted with 25 mL deionized water to Continue to stir for 6 hours, then transfer the liquid to the refrigerator for freezing for 24 hours and then move to a freeze dry...

Embodiment 3

[0025] (1) First, 0.2547g of commercial vanadium pentoxide (V 2 o 5 ) powder and 7.65mL mass percent concentration of 5% Graphene (Graphene) aqueous dispersion in a water bath at normal temperature after mixing and stirring for 5 minutes, while stirring, slowly dripping 1.15mL mass percent concentration of 30% H 2 o2 , continue to stir for 15 minutes after the dropwise addition is completed, then transfer it to an ultrasonic cleaner and add 16.2mL deionized water to dilute the solution to the concentration of vanadium pentoxide was 0.056mol / L, continued ultrasonication for 90 minutes, and obtained a black gel, left to age at room temperature for 3 days, and obtained dark brown V 2 o 5 ·nH 2 O / Graphene Gel.

[0026] (2) The V obtained in step (1) 2 o 5 ·nH 2 The O / Graphene gel was stirred, dispersed, and diluted with 25 mL deionized water to Continue to stir for 6 hours, then transfer the liquid to the refrigerator for freezing for 24 hours and then move to a freeze d...

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