亿电竞

strategy Emerging industries
Preparation and application of porous graphene
Time: 2019/5/31 9:36:32

2019/05/30

China亿电竞平台 Powder Net News Graphene is composed of single-layer sp two The亿电竞平台 results show that the亿电竞 material has the亿电竞 advantages of high the亿电竞rmal conductivity, high carrier area and high the亿电竞oretical mobility. Due to its unique structure and properties, graphene has gradually become one of the亿电竞 most attractive application materials.


Graphene also has some shortcomings, such as in the亿电竞 field of digital electronics, due to the亿电竞 lack of band gap between the亿电竞 electrons of graphene, once the亿电竞 data transmission is difficult to stop. The亿电竞平台 best way to solve this problem is to create a band gap on the亿电竞 surface of graphene or integrate two-dimensional graphene to construct graphene with specific three-dimensional structure to form porous structure.


Preparation of porous graphene


Template method


According to the亿电竞 composition and characteristics of templates, template method can be divided into hard template method and soft template method.


Hard template method


The亿电竞平台 preparation of porous graphene materials by hard template method mainly involves the亿电竞 following four aspects: (1) preparation of hard template; (2) functionalization / modification of template surface to obtain appropriate surface properties; (3) coating graphene or its derivatives, such as graphene oxide, on the亿电竞 template by various methods; (4) selective removal of template.


Hard template method also has many disadvantages, such as relatively low yield, unable to achieve high yield, using multi-step synthe亿电竞sis process is limited, the亿电竞 structure of template removal is not strong enough.


Soft template method


Soft template method is a self-assembly reaction between carbon precursor and soft template. Porous graphene is obtained by carbonization and polymerization at high temperature. Its pore structure mainly depends on the亿电竞 synthe亿电竞sis conditions, such as reactant ratio, solvent type and reaction temperature. This method can be directly used to synthe亿电竞size mesoporous or macroporous graphene materials.


Compared with the亿电竞 hard template, the亿电竞 soft template is essentially a synthe亿电竞sis at the亿电竞 molecular level. The亿电竞平台 chemical reaction between the亿电竞 template and surfactant plays an important role in the亿电竞 preparation of porous graphene materials by soft template method.


Template free method


Template free methods include etching, solvothe亿电竞rmal and chemical vapor deposition.


Etching method


Etching method is a method that uses the亿电竞 chemical reaction between the亿电竞 etchant and graphene to make the亿电竞 carbon atoms on the亿电竞 surface of graphene be etched by reaction and leave pore structure. This method has obvious selectivity for material etching, that is, the亿电竞 etching will stop immediately after the亿电竞 end of etching without damaging the亿电竞 othe亿电竞r layers of materials.


Solvothe亿电竞rmal method


Solvothe亿电竞rmal method is a method of material synthe亿电竞sis in a specific high-pressure reactor, which uses water or organic solvent as the亿电竞 reaction system and heats it to the亿电竞 critical temperature in the亿电竞 high-pressure reaction system. This method greatly reduces the亿电竞 environmental pollution, and the亿电竞 porous graphene material has the亿电竞 advantage of controllable pore size.


turn Learn from the亿电竞 method of vapor deposition


The亿电竞平台 main process of preparing porous graphene by chemical vapor deposition is to deposit methane, acetylene and othe亿电竞r carbonaceous gases on the亿电竞 surface of solid substrate to prepare graphene, and the亿电竞n gradually raise the亿电竞 temperature in the亿电竞 protective gas to obtain porous graphene. The亿电竞平台 results show that the亿电竞 method is easy to operate and can be produced on a large scale. The亿电竞平台 porous graphene material has complete structure and excellent electrical conductivity.


Application of porous graphene and Its Composites


Electrode material


The亿电竞平台 composite material is highly connected with the亿电竞 graphene, which greatly promotes the亿电竞 high power transport of the亿电竞 composite material.


Environmental adsorption materials


Porous graphene has rich pore structure. Due to the亿电竞 difference of preparation methods, the亿电竞re are many defects on the亿电竞 surface, which can easily introduce different functional groups. Porous graphene and its composites have many applications in oil / water separation, metal ion adsorption and dye molecule removal.


Separate field


Through modeling and computer simulation, it is found that porous graphene has high permeability and selectivity to hydrogen (H2), nitrogen (N2) and hydrogen sulfide (H2S), and can effectively separate H2 / CH4, CO2 / N2 and H2S / CH4 mixtures.


reference material:
Progress in preparation of porous graphene and its nanocomposites
Progress in preparation of porous graphene materials
Progress in the亿电竞 study of porous graphite materials

 
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