Co-construction of sulfur vacancies and carbon confinement in V₅S₈/CNFs to induce an ultra-stable performance for half/full sodium-ion and potassium-ion batteries

Abstract

To construct anode materials for sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs) with high energy, and long lifespan is significant and still challenging. Here, sulfur-defective vanadium sulfide/carbon fibers composite (D-V5S8/CNFs)...

Stabilizing V2O3 in carbon nanofiber flexible films for ultrastable potassium storage

“…So far, a variety of materials have been explored and used as anodes for potassium-ion batteries, such as carbon-based materials, [19][20][21][22] alloys, 23,24 organic materials, 25,26 transition metal sulfides [27][28][29][30][31][32] /oxides, [33][34][35][36][37] and so on. Compared with other materials, vanadium oxide (V 2 O 3 ) shows great potential for energy storage due to the open tunnel structure of 3D V-V frameworks, low cost and multi-electron transfers.…”

Structure Engineering of BiSbSx Nanocrystals Embedded within Sulfurized Polyacrylonitrile Fibers for High Performance of Potassium‐Ion Batteries

“…The K + diffusion coefficient in the BiSbS x @SPAN‐450 anodes was analysed by using the constant current intermittent titration technique (GITT) (Figure 5c and d). This technique was conducted at a quasi‐equilibrium current of 50 mA g −1 with a current pulse duration of 0.25 h, followed by relaxation for 3 h. As depicted in Figure 5d, the diffusion coefficient in the discharge process slightly decreases and then increases progressively in subsequent cycles, which is related to the enhancement of the conductivity credit for potassium‐ion intercalation [12] . In contrast, the decrease in the diffusion coefficient during the charging process confirms that the diffusion resistance and path length for the potassium ions are increased during the deintercalation process [65,66] …”

“…This technique was conducted at a quasi-equilibrium current of 50 mA g À 1 with a current pulse duration of 0.25 h, followed by relaxation for 3 h. As depicted in Figure 5d, the diffusion coefficient in the discharge process slightly decreases and then increases progressively in subsequent cycles, which is related to the enhancement of the conductivity credit for potassium-ion intercalation. [12] In contrast, the decrease in the diffusion coefficient during the charging process confirms that the diffusion resistance and path length for the potassium ions are increased during the deintercalation process. [65,66] To further elucidate the excellent long-term cycling stability of the BiSbS x @SPAN-450 electrode, it was cycled 100 cycles at 0.1 A g À 1 in the discharge-to-0.01 V stage for SEM and TEM measurements (Figure 6a).…”

“…In the past few years, many workable strategies have been proven to enhance the potassium storage performance of anodes, such as making use of Sn 4 P 3 , V 5 S 8 , SnS 2 , P, Bi, Sb, and Sn, combined with conversion reactions and/or alloy reactions, which can offer a high capacity for PIBs [10–19] . Bi 2 S 3 and Sb 2 S 3 are considered excellent anode materials due to their excellent theoretical volumetric capacities (625 mAh g −1 for Bi 2 S 3 and 946 mAh g −1 for Sb 2 S 3 ) and their laminar structure.…”

“…In the past few years, many workable strategies have been proven to enhance the potassium storage performance of anodes, such as making use of Sn 4 P 3 , V 5 S 8 , SnS 2 , P, Bi, Sb, and Sn, combined with conversion reactions and/or alloy reactions, which can offer a high capacity for PIBs. [10][11][12][13][14][15][16][17][18][19] Bi 2 S 3 and Sb 2 S 3 are considered excellent anode materials due to their excellent theoretical volumetric capacities (625 mAh g À 1 for Bi 2 S 3 and 946 mAh g À 1 for Sb 2 S 3 ) and their laminar structure. However, similar to other conversion and alloy reaction type anodes, Bi 2 S 3 and Sb 2 S 3 are accompanied by large volume changes and structural destruction in the charge/discharge process, leading to low capacity retention and cycling performance.…”