Hollow Iron Oxide Nanoparticles for Application in Lithium Ion Batteries

• Published in: Nano letters 2012-05, Vol.12 (5), p.2429-2435
• Main Authors: Koo, Bonil, Xiong, Hui, Slater, Michael D, Prakapenka, Vitali B, Balasubramanian, Mahalingam, Podsiadlo, Paul, Johnson, Christopher S, Rajh, Tijana, Shevchenko, Elena V
• Format: Article
• Language: English
• Subjects: Applied sciences; Cations; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Cycles; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; Fading; Intercalation; Iron oxides; Lithium; Lithium-ion batteries; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Nanocrystalline materials; Nanoparticles; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Physics; Specific phase transitions; Structural transitions in nanoscale materials; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Vacancies
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl3004286

Material design in terms of their morphologies other than solid nanoparticles can lead to more advanced properties. At the example of iron oxide, we explored the electrochemical properties of hollow nanoparticles with an application as a cathode and anode. Such nanoparticles contain very high concentration of cation vacancies that can be efficiently utilized for reversible Li ion intercalation without structural change. Cycling in high voltage range results in high capacity (∼132 mAh/g at 2.5 V), 99.7% Coulombic efficiency, superior rate performance (133 mAh/g at 3000 mA/g) and excellent stability (no fading at fast rate during more than 500 cycles). Cation vacancies in hollow iron oxide nanoparticles are also found to be responsible for the enhanced capacity in the conversion reactions. We monitored in situ structural transformation of hollow iron oxide nanoparticles by synchrotron X-ray absorption and diffraction techniques that provided us clear understanding of the lithium intercalation processes during electrochemical cycling.