Ultrasmall SnO2 Nanocrystals: Hot-bubbling Synthesis, Encapsulation in Carbon Layers and Applications in High Capacity Li-Ion Storage

Abstract

Ultrasmall SnO2 nanocrystals as anode materials for lithium-ion batteries (LIBs) have been synthesized by bubbling an oxidizing gas into hot surfactant solutions containing Sn-oleate complexes. Annealing of the particles in N2 carbonifies the densely packed surface capping ligands resulting in carbon encapsulated SnO2 nanoparticles (SnO2/C). Carbon encapsulation can effectively buffer the volume changes during the lithiation/delithiation process. The assembled SnO2/C thus deliver extraordinarily high reversible capacity of 908 mA·h·g−1 at 0.5 C as well as excellent cycling performance in the LIBs. This method demonstrates the great potential of SnO2/C nanoparticles for the design of high power LIBs.

One-pot synthesis of core–shell-structured tin oxide–carbon composite powders by spray pyrolysis for use as anode materials in Li-ion batteries

“…The CV curve for the first discharging process showed two broad reduction peaks at 0.15 and 0.65 V. The broad reduction peaks were due to the poor crystalline structure of the SnO x -carbon composite powders. The broad reduction peak observed at 0.65 V was associated with the formation of metallic Sn nanograins and amorphous Li 2 O through the reduction of SnO 2 and SnO [28,29]. The highly crystalline SnO 2 powders had a sharp reduction peak around 0.9 V in the first discharging process, as shown in Fig.…”

“…S7. The reduction peak at 0.12V was attributed to the formation of Li x Sn alloys [29]. The strong broad oxidation peak at approximately 0.5 V in the first charging process was attributed to Li dealloying from Li x Sn [28].…”

High rate capability and cyclic stability of hierarchically porous Tin oxide (IV)–carbon nanofibers as anode in lithium ion batteries

“…2). The anodic peaks observed in the first cycle at 0.13, 0.54 and 1.26 V corresponding to Li extraction, de-alloying of Li x Sn and the partially formation of SnO x , respectively, as reported in the literature (Ding et al 2014). In subsequent cycles, the peak at 0.76 V is separated into two peaks (about 0.62 and 0.92 V), that can be ascribed to the formation of the solid electrolyte interphase (SEI) and the tin oxide reduction to metallic tin.…”

“…During the first cathodic scan an irreversible reduction peak with a maximum at 0.76 V is seen which is attributed to the reduction of SnO 2 to metallic Sn and the formation of the solid electrolyte interphase (SEI) layer in the first cycle Eq. (1) (Ding et al 2014;Reddy et al 2013aReddy et al , 2015Yim et al 2011;Zhu et al 2011).…”

“…We have cycled SnO 2 -carbon nanofibers in the voltage range 0.01-1.2 V. So some extent of partial conversion reaction (Sn-SnO) could be anticipated (Ding et al 2014;Reddy et al 2013aReddy et al , 2015Yim et al 2011;Zhu et al 2011).…”