Amphiphilic Carbonaceous Material-based Carbon Electrode Materials And Their Electrochemical Energy Storage Performances

Amphiphilic carbonaceous material?ACM?possesses abundant functional groups,thermosetting property and features of pitch or coke.It consists of many rigid segments,so its structure is stable.Based on the above advantages,it exhibits great potential in energy storage.In the paper,we select coal tar pitch-based amphiphilic carbonaceous material?CP-A5?to obtain pitch-based carbon materials and discuss their application in Electric double layer capacitor?EDLC?and Lithium ion battery?LIBs?.CP-A5 was converted to mesoporous carbons?MCs?by an MgO-templated method.The yields of MCs were competitive,up to 17%.Temperature-programmed desorption?TPD?,thermogravimetric analysis?TG?,high-resolution transmission electron microscopy?HRTEM?and N₂ adsorption-desorption were applied to characterize the precursors and MgO-templated MCs.Compared with some published template carbons from thermoplastic materials,less collapse was observed due to the thermosetting property of the carbon precursor.MC73?MgO/CP-A5 at 7/3 mass ratio?had a surface area of 1991 m² g^-1 and interconnected micropores/mesopores,which endowed it with outstanding electrochemical performance under 1 M TEABF₄/PC organic electrolyte in EDLCs,namely,a gravimetric specific capacitance of 90.8 F g^-1at 0.05 A g^-1 and a capacitance retention of 91.3%after 10000 cycles at 1 A g^-1.CP-A5 with negatively charged centers can attract Fe³⁺ions in aqueous solution,so iron element can evenly disperse in CP-A5.In this composite,the size distribution of Fe₃O₄ particles is between 5 and 20 nm.Fe₃O₄ nanoparticles embed in carbon material well.The Fe₃O₄/C composite electrode displayed good electrochemical performance in LIBs.After 50 cycles,it has a high capacity of 600 mAh g^-1 at 0.05 A g^-1.This is because the carbon-coated Fe₃O₄ effectively reduced the Fe₃O₄nanoparticles aggregation,alleviated the volume expansion of Fe₃O₄ in charging and discharging process.