Sodiation vs. lithiation phase transformations in a high rate – high stability SnO₂ in carbon nanocomposite

Abstract

An SnO2-carbon nanocomposite was created by a self-assembly method. This showed promising electrochemical performance as both a Na and Li ion battery anode, with among the best cyclability and rate capability when tested against Na.

Carbon Encapsulated Tin Oxide Nanocomposites: An Efficient Anode for High Performance Sodium-Ion Batteries

“…These results are in agreement with those reported recently. 24,33 As displayed in Figure 10e, in S-EG, agglomeration of particle start to occurs because thin carbon coating is unable to accommodate the volume change. On the contrary, particle with size bellow 10nm and evenly distributed in the carbon matrix can maintain the pristine structure during insertion and desertion of Na-ion (Figure 10 f) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 To better understand the electrochemical behavior of all the synthesized carbon encapsulated tin oxide samples under the various current rates, we also investigated their C-rate performances as shown in Figure 11.…”

“…[36][37] It is presumed that the reduction peak at potential (0.4V) could correspond to the formation of SEI layer on the electrode surface and alloying of metallic Sn into α-NaSn. 24 On the other hand, the reduction peak at lower potential shell with Sn as core formed during the conversion reaction can also be a factor that impede the Sn alloying process. 26 In addition, a solid SEI layer formed on the surface of electrode can also reduce the sodiation rates and hence the discharge capacities.…”

“…The observed charge storage mechanism for the SnO 2 /C composite in the present case is in well agreement with the phase transition mechanism given for the SnO 2 /C composite in limited number of previous reports. 24,25 To support the XRD results, TEM analysis of the SnO2/C electrodes after full discharge and charge was carried and the results were summarized in the Figure 10. (Figure 10 a-c).…”

“…16 Nevertheless, the tin oxide can achieve high specific capacities by acting as a conversion type as well as alloying material to store Na. [21][22][23][24][25][26] Therefore, it could be a potential anode material for Na-ion storage.…”

Alloy‐Based Anode Materials toward Advanced Sodium‐Ion Batteries

“…Gu et al studied the sodiation and desodiation processes of SnO 2 nanowires anode using in situ transmission electron microscopy (TEM), finding that the sodiation speed was ≈1/20th of that of lithiation for SnO 2 , which was in good agreement with the density functional theory (DFT) calculation result that Na + diffusion barrier is larger than that of Li + in SnO 2 . [95] Patra et al employed supercritical CO 2 (SCCO 2 ) fluid to prepare SnO 2 nanoparticles (1 nm in diameter), which were then uniformly dispersed on graphene nanosheets (GNSs) and carbon nanotubes (CNTs). In contrast, full lithiation product Li 22 Sn 5 was easily achieved in LIBs.…”