Ultrasmall Sn Nanoparticles Embedded in Carbon as High‐Performance Anode for Sodium‐Ion Batteries

Abstract

Designed as a high‐capacity, high‐rate, and long‐cycle life anode for sodium‐ion batteries, ultrasmall Sn nanoparticles (≈8 nm) homogeneously embedded in spherical carbon network (denoted as 8‐Sn@C) is prepared using an aerosol spray pyrolysis method. Instrumental analyses show that 8‐Sn@C nanocomposite with 46 wt% Sn and a BET surface area of 150.43 m2 g−1 delivers an initial reversible capacity of ≈493.6 mA h g−1 at the current density of 200 mA g−1, a high‐rate capacity of 349 mA h g−1 even at 4000 mA g−1, and a stable capacity of ≈415 mA h g−1 after 500 cycles at 1000 mA g−1. The remarkable electrochemical performance of 8‐Sn@C is owing to the synergetic effects between the well‐dispersed ultrasmall Sn nanoparticles and the conductive carbon network. This unique structure of very‐fine Sn nanoparticles embedded in the porous carbon network can effectively suppress the volume fluctuation and particle aggregation of tin during prolonged sodiation/desodiation process, thus solving the major problems of pulverization, loss of electrical contact and low utilization rate facing Sn anode.

Electrospun NaVPO4F/C Nanofibers as Self‐Standing Cathode Material for Ultralong Cycle Life Na‐Ion Batteries

“…It is worth mentioning that our group also carried out some related works about anode materials for SIBs. [6][7][8][9][10] However, the lack of suitable cathode materials is still a major obstacle to the commercial application of SIBs. Hence, it is still an arduous challenge to find appropriate cathode materials with high power capability, long cycle life, and good safety.…”

“…[31,32,34] Hence, it is significant to enhance the kinetics of Na-ion transfer in NaVPO 4 F. In order to achieve this goal, strategies mainly include decreasing the crystallite size and altering morphology of the material. [7,22,35,36] As far as we know, electrospinning is a versatile technique to prepare various 1D carbon-containing composites and produce flexible membrane, [6,8,[37][38][39] which encourages us to fabricate NaVPO 4 F with novel morphology combined the method of electrospinning to improve its electrochemical performance.Herein, we first synthesized 1D NaVPO 4 F/C nanostructure via an electrospinning method. Such a structure combines a variety of advantages for battery electrodes: (I) the small nanoparticles (≈6 nm) shorten the length of Na-ion transport; (II) NaVPO 4 F has received a great deal of attention as cathode material for Na-ion batteries due to its high theoretical capacity (143 mA h g −1 ), high voltage platform, and structural stability.…”

SnS/C nanocomposites for high-performance sodium ion battery anodes

“…8,14 Instead, other alloy-type materials such as Sn-, Sb-, and Ge-based materials have been examined in detail as high-capacity anodes for SIBs. [15][16][17][18][19][20][21][22][23][24][25] In addition, it has been reported that various transition metal oxides, suldes and selenides can store sodium ions reversibly through intercalation and/or conversion reactions.…”

Edge Engineering of MoS2 Nanoribbons as High Performance Electrode Material for Na‐ion Battery: A First‐Principle Study

“…Plenty of studies have been focused on the anodes based on conversion mechanism, such as metal oxides/sulfides (Fe 2 O 3 , CoS 2 , FeS 2 ) [3][4][5] and alloy compounds (P, Sn, Ge, Sb and their alloying complexes). [6][7][8][9] However, these anodes suffer from severe structure destruction and volume expansion during the Na-ion insertion and extraction, leading to poor cycling performance. As a comparison, layered intercalation mechanism anodes such as graphite, [10,11] Na 2 Ti 3 O 7 [12,13] and P2-Na 0.66 - [Li 0.22 Ti 0.78 ]O 2 [14] display better cycling performance but with low specific capacity.…”