Dense Sandwich‐like Na₂Ti₃O₇@rGO Composite with Superior Performance for Sodium Storage

Abstract

Sodium titanate (Na 2 Ti 3 O 7 ) has been considered as a promising anode in sodium-ion batteries (SIBs) because of its low working voltage, high energy density and low cost. However, low electronic and ionic conductivity become the major obstacles to affect the improvement of its electrochemical performance.Here, based on the high specific surface area and high conductivity of reduced graphene oxides (rGO), a dense sandwich-like structure was built through a facile hydrothermal route. The Na 2 Ti 3 O 7 @rGO (NTO@rGO) composites have a stable two-dimensional conductive network framework and the Na 2 Ti 3 O 7 particles grow in situ on the surface of the rGO nanosheets, greatly improving the utilization of rGO by reducing the introduction of rGO. Moreover, when the NTO@rGO was used as an anode for SIBs, it showed an excellent cycle stability and rate performance with 137 mAh g À 1 at 100 mA g À 1 after 500 cycles and 92 mA g À 1 at 2 A g À 1 , respectively.

A high-rate capability and energy density sodium ion full cell enabled by F-doped Na2Ti3O7 hollow spheres

“…Clearly, the electrochemical properties of F-NTO HSs, both in cycle life and rate performances, were much superior to those obtained in other NTO involving works (with detailed performances compared in Table S2†). 18–23,28,31,32,47,52–61 The above analysis further demonstrated the advantages of the F-NTO HS electrode upon cycling, even at an extraordinary high rate, implying its feasibility as a high capacity anode with good kinetics behavior for SIBs. Moreover, excellent electrochemical performances could be found for the NVP@C|F-NTO HS full cell.…”

“…14 Moreover, it showed the lowest Na intercalation potential compared with other reported insertion-type oxides (0.3 vs. Na/Na + ), [15][16][17] which contributed to higher working voltage and energy density for practical application. 18 Notwithstanding, the NTO anode was still challenged by the following disadvantages: 19,20 (i) the collapse of NTO layers due to the huge volume change upon Na + insertion/ extraction nally led to fast capacity decay; 21 (ii) low electronic conductivity (induced by the wide bandgap of 3.7 eV) and poor Na + diffusion kinetics (3.5 Â 10 −12 cm 2 s −1 ) resulted in sluggish e − /Na + transportation.…”

An expanded sandwich-like heterostructure with thin FeP nanosheets@graphene via charge-driven self-assembly as high-performance anodes for sodium ion battery

“…It has already been demonstrated that incorporating 2D active materials into 2D material interlayers such as graphene and MXene as spacers could effectively prevent the natural restacking of 2D active materials. This approach resulted in enhanced electrochemical performances for MnO 2 nanosheets/graphene, 19 Sb nanosheets/graphene, 20 Na 2 Ti 3 O 7 nanosheets/graphene, 21 phosphorene nanosheets/MXene, 22 and MoS 2 nanosheets/graphene. 23 Because of the superior electrical conductivity afforded by the carbon matrices, which ensures excellent electron transfer in the charge/discharge operation, the electrochemical performance in terms of specific capacity has been greatly increased.…”

Preparation of Porous Zn0.76Co0.24S Yolk‐Shell Microspheres with Enhanced Electrochemical Performance for Sodium Ion Batteries

“…Nonetheless, with the large‐scale application of LIBs, the increasing shortage of lithium resources has restricted their development. Therefore, the scientific intention has been attracted to sodium‐ion batteries (SIBs) because of their low cost and sodium‐rich resources [11–12] . Nevertheless, the radius of lithium ions is smaller than that of sodium ions, which causes that the commercial electrode materials for LIBs, such as graphite materials, are not suitable for SIBs [13–14] .…”

“…Therefore, the scientific intention has been attracted to sodium-ion batteries (SIBs) because of their low cost and sodium-rich resources. [11][12] Nevertheless, the radius of lithium ions is smaller than that of sodium ions, which causes that the commercial electrode materials for LIBs, such as graphite materials, are not suitable for SIBs. [13][14] Electrode materials largely determine the electro-chemical performance of batteries.…”