Monodisperse Antimony Nanocrystals for High-Rate Li-ion and Na-ion Battery Anodes: Nano versus Bulk

• Published in: Nano letters 2014-03, Vol.14 (3), p.1255-1262
• Main Authors: He, Meng, Kravchyk, Kostiantyn, Walter, Marc, Kovalenko, Maksym V
• Format: Article
• Language: English
• Subjects: Anodes; Antimony; Charge; Charge density; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Current density; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Nanocrystalline materials; Nanocrystals; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Physics; Storage capacity; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl404165c

We report colloidal synthesis of antimony (Sb) nanocrystals with mean size tunable in the 10–20 nm range and with narrow size distributions of 7–11%. In comparison to microcrystalline Sb, 10 and 20 nm Sb nanocrystals exhibit enhanced rate-capability and higher cycling stability as anode materials in rechargeable Li-ion and Na-ion batteries. All three particle sizes of Sb possess high and similar Li-ion and Na-ion charge storage capacities of 580–640 mAh g–1 at moderate charging/discharging current densities of 0.5–1C (1C-rate is 660 mA g–1). At all C-rates (0.5–20C, e.g. current densities of 0.33–13.2 Ag1–), capacities of 20 nm Sb particles are systematically better than for both 10 nm and bulk Sb. At 20C-rates, retention of charge storage capacities by 10 and 20 nm Sb nanocrystals can reach 78–85% of the low-rate value, indicating that rate capability of Sb nanostructures can be comparable to the best Li-ion intercalation anodes and is so far unprecedented for Na-ion storage.