Poly(1,5-anthraquinonyl sulfide)/reduced graphene oxide composites towards high Li and Na storage both in half- and full-cells.

Conjugated carbonyl compounds with high theoretical capacity, low cost, structural flexibility and abundant resources are potential cathodes in metal-ion batteries (lithium-LIBs, sodium-SIBs, kalium-KIBs). Regrettably, their inherent drawbacks of high solubility and low electrical conductivity limit their further application. Herein, different mass ratios of reduced graphene oxide wrapped poly (1,5-anthraquinonyl sulfide) (PAQS/rGO) composites were prepared through a calcination-treatment process aiming at decreasing the dissolution and enhancing the conductivity. XRD, FTIR and Raman analysis confirmed the successful synthesis of PAQS. XRD analysis also confirmed the conversion of GO to rGO. Four-probe test results showed that the conductivity of composites increased as the rGO ratio increased. SEM images showed that PAQS/rGO composites presented microsphere morphologies. Profiting from the enhanced conductivity and limited dissolution in electrolyte, the PAQS2 (the mass ratios of PAQS and rGO is 10:2) composite exhibited outstanding performance both in half- and full-batteries. In LIBs/SIBs, PAQS2 exhibited reservable discharge capacities of 121 and 115 mAh g−1 at 50 mA g−1 after 200 and 400 cycles, respectively. In PTPAn/PAQS2 all-organic Li/Na-ion batteries, reservable charge/discharge capacities of 42.1/39 and 42.1/40.4 mAh g−1 were retained at 50 mA g−1 after 200 cycles, respectively. Ex-situ FT-IR analysis further performed the redox reaction of carbonyl groups during charging and discharging. [ABSTRACT FROM AUTHOR]