Facile fabrication of novel heterostructured tin disulfide (SnS2)/tin sulfide (SnS)/N-CNO composite with improved energy storage capacity for high-performance supercapacitors

•Novel SnS2/SnS/N-CNO composite was syntheiszed by solvothermal and pyrolysis methods.•Heterostructured SnS2/SnS/N-CNO improves conductivity and electrochemical performance.•SnS2/SnS/N-CNO electrode delivered superior specific capacitance of 741.67 F g−1.•SnS2/SnS/N-CNO showed excellent cycling stability (95%) retention after 2000 cycles.•Heterostructured composite electrode exhibited excellent power and energy densities. The unique properties of the Sn-S system made it a high sensitiveness nanomaterial for prepare higher-performance supercapacitors. The heterostructured SnS2/SnS and N-CNOs were synthesized by simple solvothermal and pyrolysis methods, respectively. To improve the conductivity of the SnS2/SnS composite, N-CNOs were added to the pristine SnS2/SnS. Herein, an ultrasensitive supercapacitor based on SnS2/SnS and N-CNOs was fabricated. Compared to the pristine SnS2/SnS heterostructured composite, SnS2/SnS/N-CNO showed high supercapacitance performance due to the increase in conductivity with the addition of C-based N-CNOs. Regarding that SnS2/SnS/N-CNO has superior electrochemical performances comparable to SnS2/SnS, because of the fast electronic transportations and volume changes in the formations of SnS2/SnS/N-CNO heterostructures. The electrochemical performance of the SnS2/SnS/N-CNO electrode enhanced specific capacitance value of 741.67 F g−1 from SnS2/SnS electrode specific capacitance of 350 F g−1 at a 0.5 A g−1 and it showed excellent cycling stabilities of 95% retention even after 2000 cycles. The obtained results suggest that the SnS2/SnS/N-CNO is efficient to be applicable as a novelelectro-active sourcein supercapacitor devices to render higher performances and stable energy storage applications.