Lithium storage performance of {010}-faceted and [111]-faceted anatase TiO2 nanocrystals

Abstract

As a popular anode material for lithium-ion batteries, anatase TiO2 nanoparticles with exposed {001} facets usually exhibit exceptional lithium storage performance owing to more accessible sites and fast migration of lithium ions along the good crystalline channels. However, there are few researches on the lithium storage capability of TiO2 nanocrystals with other high-energy facets owing to lack of effective synthesis method for controlling crystal facets. Herein, anatase TiO2 nanocrystals with exposed {010}- and [111]-facets are successfully prepared by using the delaminated tetratitanate nanoribbons as precursors. The electrochemical properties of these TiO2 nanocrystals with high-energy surfaces and the comparison with commercial TiO2 nanoparticles (P25) are studied. It is found that the cycle and rate performance of TiO2 nanocrystals is highly improved by reducing the particle size of nanocrystals. Moreover, TiO2 nanocrystals with exposed {010}- and [111]-facets exhibit better lithium storage capacities in comparison with P25 without a specific facet though P25 has smaller particle size than these TiO2 nanocrystals, indicating that the exposed facets of TiO2 nanocrystals have an important impact on their lithium storage capacity. Therefore, the synthesis design of high-performance TiO2 materials applied in the next-generation secondary batteries should both consider the particle size and the exposed facets of nanocrystals.