Advanced Carbon Materials Improving The Performance Of Organic Cathode Material C4Q For Lithium/Sodium Ion Batteries

At present,the mostly electrode materials of lithium/sodium ion batteries are based on transition metal inorganic compounds with expensive,non-renewable and polluting the environment,which is contrary to the concept of"sustainable development".The electroactive organic compound is one of the most potential electrode materials for the next generation.Calix[4]quinone?C4Q?is a quinone derivative of calix[4]arene,the annular macromolecule C4Q contains four p-quinone units linked by four methylene groups,and the eight active centers are capable of reversible electrode reactions.With the high theoretical capacity of(447 mAh g^-1),abundant resources,environmental friendliness and safe system,C4Q has attracted wide attention in recent years.However,the poor conductivity and large solubility in liquid electrolyte limit its application.The method of using conductive carbon materials optimized with C4Q to form a composite electrode material makes it possible to solve both problems at the same time.Herein,the ternary composites C4Q/CMK-3/SWCNTs were prepared,the porous carbon material CMK-3 and single-walled carbon nanotubes?SWCNTs?were used to co-stabilize the C4Q.In addition,two kinds of biomass carbon?NACF,PPL?were prepared to encapsulate C4Q.The electrochemical properties of C4Q/NACF,C4Q/PPL composites were studied.The lithium/sodium storage properties of different composites are as follows:C4Q/CMK-3/SWCNTs composites:for lithium-ion batteries,the results show that the electrochemical performance is superior than others when the mass fractions of the three components were 30 wt%,30 wt%and 30 wt%,respectively.After 100 cycles,the capacity was 238.7 mAh g^-1.Even at 1 C,the discharge capacity is still about 260 mAh g^-1.For sodium ion batteries,when the mass of each component was 40 wt%,40 wt%,and 10 wt%,respectively,the performance of the batteries is optimal.At 0.1 C,the initial discharge specific capacity can reach 441 mAh g^-1,and the capacity retention rate is still66%after 100 cycles.Even at 1 C,the capacity is still of 346 mAh g^-1.C4Q/NACF,C4Q/PPL composites:for lithium-ion batteries,after 100 cycles at 0.1C,the capacity decay to 162.4 mAh g^-1,185.3 mAh g^-1.At 1 C,the capacity is still of141.7 mAh g^-1,165.2.mAh g^-1,respectively.For sodium ion batteries,C4Q/NACF and C4Q/PPL composites with a capacity of 421.7 mAh g^-1 and 435.3 mAh g^-1and decay to113.5 and 130 mAh g^-1 after 100 cycles,respectively.When the current density increases to 1 C,the capacitiy is 120 mAh g^-1 and 150 mAh g^-1.