Researches On The Supercapacitive Performance Of New Types Of Metal?Doped Porous Carbon Materials

Energy is the lifeblood of the national economy and has a profound impact on the global economy and the world pattern.With the advancement of Science and technology and the rapid development of social economy,the problem of energy is becoming more and more important,especially the consumption of non-renewable energy such as fossil energy and the increasingly serious environmental pollution has become an urgent problem to be solved by mankind in the 21 st century.Super capacitors have the characteristics of ultra-high capacitance,low leakage current,high power density,high charge and discharge efficiency,long life,long time and wide temperature range.Carbon materials are used as an important electrode material in supercapacitors because of their variety,low price and high specific surface area,high conductivity,excellent electrochemical stability and cyclic stability.But carbon materials also have the disadvantage of lower capacitance and less energy density.Another major component of supercapacitor electrode material is a metal pseudo capacitor material with redox properties.Compared with carbon material,the metal pseudo capacitance material has the advantages of higher capacitance,higher energy density,poor cycle life and potential range.In recent years,the combination of the metal pseudo capacitor material and the carbon material can not only play the advantages of two kinds of materials,but also make up the disadvantage of both,which is more and more valued by people.This paper mainly based on three different ideas,the synthesis of three kinds of metal-doped porous carbon materials.The microstructure and electrochemical properties of the composites were studied.In the first,a polymer containing ti was synthesized by crafts reaction,and then a titanium-doped porous carbon material was obtained under N2 protection under the Ti Salophen of complexes.With a small surface area complex,the 1044 m2?g-1 polymer is synthesized,and the titanium-doped porous carbon material contains a flake structure,which increases the specific surface area and facilitates the ion electron passage.The results show that the charge-discharge potential window of metal dopingis increased than that of non doped porous carbon(1 V add to 1.5 V).When the current density is at 1 a g-1,the capacitance is increased by 111.2 F?g-1 to 134.9 F?g-1,and after 1000 cycles,the capacitance remains 93.44%.The possibility of metal complexes as the precursor of carbon precursors and potential applications as electrode materials for supercapacitors are indicated.The second,with egg film as the base,hydrothermal method on the egg film growth Co4s3,and then under the protection of N2 carbonizing obtained Co4S3 doped porous carbon material Co4S3.The Co4S3 granule grows directly on the egg membrane structure skeleton by hydrothermal method,and the Co4S3 electrode composite was prepared after carbonization.Through SEM,we can see that the porous skeleton structure of the egg membrane provides more space for the Co4S3 attachment.Co4S3 is successful and more evenly grown in the egg membrane skeleton,after carbonization Co4S3 still and C closely together.In the electrochemical test,it can be found that the composites widen the potential window,which can synthesize the properties of high specific surface area of carbon materials,excellent conductivity and Co4S3 of the pseudo capacitance properties,and the materials exhibit good electrochemical properties and capacitance properties.After 1000 times,the capacitance is still 86.2%,which has a good cyclic stability,and when the current density is 1 A?g-1,the capacitance reaches 167.2 F?g-1.Compared with the carbon material after Co4S3 and egg film carbonization,the electrochemical properties of Co4S3/C composites were significantly improved.All these show that the egg film is an excellent application foreground for composite substrates.Third,the first hydrothermal synthesis of tubular MnO2,and then in the MnO2,the outer package of a layer of SiO2,to SiO2 as a template long a layer of polymer,under the N2 protection after carbonization to wash template SiO2,the first synthesis of nuclear shell structure MnO2 manganese-doped porous carbon composite materials.The structural characterization and electrochemical measurement of the MnO2core-shell composite carried out,and it was found that the MnO2 exterior of the hydrothermal synthesis was uniformly encapsulated with a porous carbon structure the porous carbon material not only greatly increases the conductivity of the MnO2,but also provides a channel for the oxidation-reduction reaction and electron transferof the MnO2,which improves the electrochemical performance of the material.When the current density is 1?A?g-1,the performance is significantly higher than the capacitance to 196.2 F?g-1,compared to the pure MnO2(33 F?g-1)and carbon material(113.2 F?g-1).