Sb₂O₃@Sb nanoparticles impregnated in N-doped carbon microcages for ultralong life and high-rate sodium ion batteries

Abstract

Antimony-based materials have been considered as highly competitive anodes for sodium-ion batteries (SIBs) because of their high theoretical capacity. However, the poor rate capability and fast capacity fading originated from...

Confining MoSe2 Nanosheets into N-Doped Hollow Porous Carbon Microspheres for Fast-Charged and Long-Life Potassium-Ion Storage

“…Spraying this solution under 200 °C could obtain hollow microspheres in which KCl cubes were evenly embedded into the polymer shell and inner surface (Figure S1a,b) The hollow structure was mainly due to the temperature gradient between the inside and outside of microspheres. 29 Second, after carbonizing polymer, (NH 4 ) 6 Mo 7 O 24 •4H 2 O tended to transform itself into intermediate Mo 2 N, which in situ maintained in the carbon shell containing a lot of holes that originated from driving KCl crystal away (written as Mo 2 N@C) (Figure S1c−f). The hollow and porous structure can effectively accelerate the penetration of electrolyte and shorten the diffusion path of electrons/ions.…”

“…Galvanostatic intermittent titration technique (GITT) was also used to calculate the potassium-ion diffusion coefficient (D) of MoSe 2 @N-HCS and its control samples during the discharge/charge processes (Figure 4b). The values of D were calculated according to the following formula (eq 1): 19,29,43…”

“…Among them, C 4 H 4 O 6 K 2 ·1/2H 2 O also played the role of making internal pores of MoSe 2 @N-HCS, C 6 H 17 N 3 O 7 could also be used as a nitrogen source, and CMC was conducive to spheroidization due to its viscosity. Spraying this solution under 200 °C could obtain hollow microspheres in which KCl cubes were evenly embedded into the polymer shell and inner surface (Figure S1a,b) The hollow structure was mainly due to the temperature gradient between the inside and outside of microspheres . Second, after carbonizing polymer, (NH 4 ) 6 Mo 7 O 24 ·4H 2 O tended to transform itself into intermediate Mo 2 N, which in situ maintained in the carbon shell containing a lot of holes that originated from driving KCl crystal away (written as Mo 2 N@C) (Figure S1c–f).…”

“…Galvanostatic intermittent titration technique (GITT) was also used to calculate the potassium-ion diffusion coefficient ( D ) of MoSe 2 @N-HCS and its control samples during the discharge/charge processes (Figure b). The values of D were calculated according to the following formula (eq ): ,, where τ, Δ E s and Δ E τ are the current pulse time and balance voltage change caused by current pulse and voltage variation during constant current pulse (Figure S7a), respectively. The calculated results showed that the average ion diffusion coefficients of MoSe 2 @N-HCS were 3.8 × 10 –9 and 6.6 × 10 –9 cm 2 s –1 in the discharge and charge states, respectively, which were larger than those of MoSe 2 @N-HCS-no-PDA, MoSe 2 @HCS, commercial MoSe 2 , and N-HCS (Figure c,d and Table S3).…”

Engineering Nanostructured Antimony-Based Anode Materials for Sodium Ion Batteries

“…Apart from the aforementioned routines, high-energy ball milling has also been intensively used to realize well-dispersive distribution or formation of intermetallic alloying compounds [40][41][42]. Besides, the spraying method is an effective method for synthesizing 0D nanostructures, for example, pitaya-like Sb@C microspheres are prepared successfully by facile aerosol spray drying synthesis [43].…”