SnS2-gC(3)N(4)/rGO Composite Paper as an Electrode for High-Performance Flexible Symmetric Supercapacitors

The flexible, free-standing, durable SnS2-gC(3)N(4)/rGO paper material was prepared by vacuum filtration of the composite dispersion containing GO and the SnS2-gC(3)N(4) composite structure which is synthesized by a simple hydrothermal method. The as-prepared SnS2-gC(3)N(4)/GO composite paper was converted to SnS2-gC(3)N(4)/rGO paper material by applying a chemical reduction process. SnS2-gC(3)N(4)/rGO paper material was characterized by using FESEM, XRD, Raman, XPS, and EIS spectroscopy techniques. The SnS2-gC(3)N(4) composite, a porous flower-like structure, uniformly intercalated between the graphene nanosheets exhibited excellent mechanical stability, greatly improved active surface areas, and enhanced surface porosity, in comparison with the pristine rGO paper. SnS2-gC(3)N(4)/rGO composite paper material show a highest specific capacitance of 532 F g(-1) at 1 A g(-1) and good cycling stability with capacitance retention of 60 % at 4 A g(-1) after 5000 cycles. Moreover, SnS2-gC(3)N(4)/rGO composite paper demonstrate an excellent supercapacitor performance compared to the gC(3)N(4)/rGO paper and pristine rGO paper. The flexible symmetric supercapacitor based on SnS2-gC(3)N(4)/rGO composite electrode exhibits remarkable mechanical flexibility, high capacitive performance (403 F g(-1) at 1 A g(-1)) and high cycle stability (63.8% at 4 A g(-1) after 1500 cycles). As a result, SnS2-gC(3)N(4)/rGO composite paper material is expected to be a promising material for high-performance energy storage applications.