Rational structure design and regulation are of paramount importance for obtaining electrode materials with desirable electrochemical performance.Here,a novel binder-free electrode with the hollow Co_(9)S_(8) core@mul...Rational structure design and regulation are of paramount importance for obtaining electrode materials with desirable electrochemical performance.Here,a novel binder-free electrode with the hollow Co_(9)S_(8) core@multi-shell structure(CS-x@MXene@Bi_(2)O_(3))derived from metal-organic frameworks(MOFs)precursor is well designed by the electrospinning,sulfuration,carbonization,and hydrothermal processes.In this architecture,the concentration of Co_(9)S_(8)(CS-x)is optimized for an ideal flexible substrate,which alleviates the dimensional variation for long cycle life.The unique cores and the MXene flakes engineered by Bi_(2)O_(3) multiple shells can be responsible for the superior characteristics,including a fast electronic pathway,large specific surface area,enhanced electrical conductivity,and improved electrochemical performance.As expected,the obtained CS-2@MXene@Bi_(2)O_(3) binder-free electrode exhibits a high discharge capacitance of 646.1 F g^(–1)(1 A g^(–1)).Two binder-free electrodes can be assembled into a solid-state supercapacitor with desirable energy and power density,and long-term cyclic stability is demonstrated through 5000 cycles.Given these advantages,the CS-2@MXene@Bi_(2)O_(3) is selected as the electrode in a foldable supercapacitor.More importantly,the specific capacitance is reserved after various deformations.Therefore,it is expected that binder-free electrode materials with the unique core@shell structure design could be applied in wearable and portable energy conversion devices.展开更多
基金support from the National Natural Science Foundation of China(no.52072307)。
文摘Rational structure design and regulation are of paramount importance for obtaining electrode materials with desirable electrochemical performance.Here,a novel binder-free electrode with the hollow Co_(9)S_(8) core@multi-shell structure(CS-x@MXene@Bi_(2)O_(3))derived from metal-organic frameworks(MOFs)precursor is well designed by the electrospinning,sulfuration,carbonization,and hydrothermal processes.In this architecture,the concentration of Co_(9)S_(8)(CS-x)is optimized for an ideal flexible substrate,which alleviates the dimensional variation for long cycle life.The unique cores and the MXene flakes engineered by Bi_(2)O_(3) multiple shells can be responsible for the superior characteristics,including a fast electronic pathway,large specific surface area,enhanced electrical conductivity,and improved electrochemical performance.As expected,the obtained CS-2@MXene@Bi_(2)O_(3) binder-free electrode exhibits a high discharge capacitance of 646.1 F g^(–1)(1 A g^(–1)).Two binder-free electrodes can be assembled into a solid-state supercapacitor with desirable energy and power density,and long-term cyclic stability is demonstrated through 5000 cycles.Given these advantages,the CS-2@MXene@Bi_(2)O_(3) is selected as the electrode in a foldable supercapacitor.More importantly,the specific capacitance is reserved after various deformations.Therefore,it is expected that binder-free electrode materials with the unique core@shell structure design could be applied in wearable and portable energy conversion devices.