Recrystallization synthesis of disodium rhodizonate-conductive polyaniline composite with high cyclic performance as cathode material of sodium-ion battery

Abstract

Disodium rhodizonate (Na2C6O6) as an organic cathode material has broad application prospects in sodium-ion batteries (SIBs) due to its high theoretical specific capacity. However, Na2C6O6 may fall off the current collector in the electrochemical cycle, which causing the capacity to decay rapidly. In this paper, a Disodium rhodizonate-conductive polyaniline (Na2C6O6-PANI) composite was prepared by antisolvent precipitation method. The surface of Na2C6O6 produced by pulverization can still contact the surface of conductive polyaniline (PANI), which prevent the active material from separating from the conductive agent. The high conductivity of conductive polyaniline can reduce the higher impedance that caused by poor contact between the crushed Na2C6O6 and current collector in the electrochemical cycle. At a current density of 500 mA g−1 in the voltage range of 0.5–3.2 V, the discharge specific capacity of Na2C6O6-PANI (9:1) has 174 mAh g−1 after 50 cycles and the capacity retention rate is 63%. This modification method provides a strategy for improving electrode materials based on quinones.