Solvent‐Free Synthesis of Uniform MOF Shell‐Derived Carbon Confined SnO2/Co Nanocubes for Highly Reversible Lithium Storage

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2017-10, Vol.13 (37), p.n/a
• Main Authors: He, Qiu, Liu, Jinshuai, Li, Zhaohuai, Li, Qi, Xu, Lin, Zhang, Baoxuan, Meng, Jiashen, Wu, Yuzhu, Mai, Liqiang
• Format: Article
• Language: English
• Subjects: carbon‐confined nanocubes; Chemical synthesis; Heat treatment; Lithium-ion batteries; lithium‐ion battery; Low cost; Metal oxides; MOF shell; Nanotechnology; Rechargeable batteries; SnO2; Solvents; solvent‐free synthesis; Storage batteries; Synergistic effect; Tin dioxide; Tin oxides
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.201701504

Tin dioxide (SnO2) has attracted much attention in lithium‐ion batteries (LIBs) due to its abundant source, low cost, and high theoretical capacity. However, the large volume variation, irreversible conversion reaction limit its further practical application in next‐generation LIBs. Here, a novel solvent‐free approach to construct uniform metal–organic framework (MOF) shell‐derived carbon confined SnO2/Co (SnO2/Co@C) nanocubes via a two‐step heat treatment is developed. In particular, MOF‐coated CoSnO3 hollow nanocubes are for the first time synthesized as the intermediate product by an extremely simple thermal solid‐phase reaction, which is further developed as a general strategy to successfully obtain other uniform MOF‐coated metal oxides. The as‐synthesized SnO2/Co@C nanocubes, when tested as LIB anodes, exhibit a highly reversible discharge capacity of 800 mAh g−1 after 100 cycles at 200 mA g−1 and excellent cycling stability with a retained capacity of 400 mAh g−1 after 1800 cycles at 5 A g−1. The experimental analyses demonstrate that these excellent performances are mainly ascribed to the delicate structure and a synergistic effect between Co and SnO2. This facile synthetic approach will greatly contribute to the development of functional metal oxide‐based and MOF‐assisted nanostructures in many frontier applications. A facile solvent‐free method is developed to synthesize uniform carbon‐confined SnO2/Co nanocubes, which exhibit excellent anodic performance in lithium‐ion batteries owing to the delicately constructed nanostructure. An introduced new conception to obtain uniform metal–organic framework (MOF) shells for metal oxides will greatly promote the development of high‐efficiency electrodes and the application of MOFs in energy storage.