Dongdong Li,Junzhi Li,Mingrui Wang,Guangshe Li,Gennadi Milinevsky,Lili Wang,Wei Han
Low energy density remains a major obstacle limiting the development and application of flexible sodium-ion batteries (SIB). Thus, this study aimed to eliminate non-active materials in electrodes, which can be a feasible way to increase the energy density of SIBs. An anode made up of flexible, free-standing SnS 2 /Sb 2 S 3 /Ti 3 C 2 T x composite carbon nanofibers (SnSbS/T-M@CNF), a Na 3 V 2 (PO 4 ) 3 composite carbon nanofibers cathode (NVP@CNF), and composite gel polymer fiber electrolytes (CGPFE) were successfully synthesized through electrospinning. MXene nanosheets improved the electrical conductivity of the SnSbS/T-M@CNF electrode and absorbed sodium sulfide, inhibiting the loss of S during the reaction. Consequently, the SnSbS/T-M@CNF free-standing electrode could be stably cycled for 1000 cycles at a current density of 1 A g −1 and maintained a reversible capacity of 397.6 mAh g −1 . Further, the NVP@CNF cathode and CGPFE quasi-solid electrolyte half-cells had an excellent cycle stability and rate performance. The flexible, free-standing SnSbS/T-M@CNF anode and NVP@CNF cathode were assembled into quasi-solid-state full cells to test their application value. The SnSbS/T-M@CNF||CGPFE||NVP@CNF full cell had a very low resistance and could easily power a 3 V LED chest lamp. After 500 cycles, it maintained a discharge capacity of 153 mAh g −1 under a current density of 0.5 A g −1 .
Shijian Wang,Shuaishuai Liu,Xuemei Li,Cong Li,Rui Zang,Zengming Man,Yuhan Wu,Pengxin Li,Guoxiu Wang
Graphical Heterostructured electrode : Composites of SnS 2 /Sb 2 S 3 heterostructures with reduced graphene oxide (rGO) nanosheets were synthesized by a facile one-pot hydrothermal method. The SnS 2 /Sb 2 S 3 heterostructures show fast Na + diffusion kinetics, and the SnS 2 /Sb 2 S 3 @rGO composites exhibit superior rate performance when used as anodes for sodium-ion batteries (see figure). Tin disulfide, as a promising high-capacity anode material for sodium-ion batteries, exhibits high theoretical capacity but poor practical electrochemical properties due to its low electrical conductivity. Constructing heterostructures has been considered to be an effective approach to enhance charge transfer and ion-diffusion kinetics. In this work, composites of SnS 2 /Sb 2 S 3 heterostructures with reduced graphene oxide nanosheets were synthesized by a facile one-pot hydrothermal method. When applied as anode material in sodium-ion batteries, the composite showed a high reversible capacity of 642 mA h g −1 at a current density of 0.2 A g −1 and good cyclic stability without capacity loss in 100 cycles. In particular, SnS 2 /Sb 2 S 3 heterostructures exhibited outstanding rate performance with capacities of 593 and 567 mA h g −1 at high current densities of 2 and 4 A g −1 , respectively, which could be ascribed to the dramatically improved Na + diffusion kinetics and electrical conductivity.