Study On The Structure Regulation And Electrochemical Performance Of Asphalt - Based Porous Carbon

In recent years, haze-based environmental problems have seriously affected people’s daily lives and healtho Therefore, in order to reduce pollution, the government strongly advocate replacing oil burning cars with new energy vehicles. Supercapacitors is a new type of energy storage device with the advantages of high power density and long cycle life, which will be the irreplaceable component in new energy vehicles. With high surface area, good chemical stability, low cost and ease of preparation, porous carbon was selected as the preferred supercapacitor electrode material. Coal tar pitch has the advantages of low prices, rich sources and high carbon content, thus it’s a unique material to prepare porous carbon electrode material with coal tar pitch.In this paper, Pitch oxide (PO) was prepared by treatmenting pitch with mixed acid, and PO acted as porous carbon precursor. This paper examines the morphology, surface functional groups, specific surface area and electrochemical properties of the obtained porous carbon. The results include the following three aspects:(1) Calcium carbonate acted as the template for the preparation of porous carbon materials. With the increase in the ratio of template added, the specific surface area of the material is increased; when the ratio is 1:1, the best activation ratio, specific surface area reaches 1049m2/g; whereas when the ratio continues to increase, the specific surface area substantially unchanged due to the excess template scattered unevenly. The porous carbon P-Ca-1 in 6M KOH electrolyte, with a high capacitance of 230 F g-1 at 0.1 A g’1(2) After the graphene oxide (GO) and PO mixed in different proportions, using one-step KOH activation to prepare porous carbon. The as-prepared porous carbon possessed high specific surface area (2196 m2/g), rich nitrogen and oxygen, appropriate mesopore/micropore ratio (mesoporosity of 47.6%) and considerable small-sized mesopores (4 nm). As a result, an outstanding capacitive performance, including high capacitance (296 F g-1) and ultrahigh-rate performance (192 F g-1 at 10A g-1) in 6 M KOH aqueous electrolyte was achieved. The capacitive performance is better than most carbon material, while with less KOH and simpler preparation.(3) Ferric citrate works as template for preparing porous carbon material. Ferric citrate not only acted as pore-forming agent but also acted as carbon source, then porous carbon materials were successfully fabricated by high temperature carbonization. The effects of different proportions of activators on the properties of the products were discussed. The results show that when the PO and ferric citrate at the ratio of 1:2, the sample shows excellent electrochemical properties and cycling stability.