Solvothermal synthesis of Li-Al layered double hydroxides and their electrochemical performance

In this paper, for the first time, Li/Al layered double hydroxides (LDHs) were synthesized by a facile and environment-friendly solvothermal approach. X-ray diffraction patterns show that the as-prepared products belong to the hexagonal phase. Well-defined LDHs particles with spiral-shape (1-2 mu m), hexagonal (2-3 mu m) and petal-like structures (10-15 mu m) have been successfully fabricated by adjusting the content of water/ethanol in the synthesis process. A possible growth mechanism was proposed for the formation of these structures. Their electrochemical performances were investigated by cyclic voltammetry, galvanostatic charge/discharge test and electrochemical impedance spectroscopy. The hexagonal Li/Al LDHs calcined at 450 degrees C exhibit the specific capacitance of 848 F g(-1) at a current density of 1.25 A g(-1). The high specific capacitance and remarkable rate capacity of Li/Al LDHs are promising for applications in capacitors and low-cost aqueous lithium ion batteries. (C) 2012 Elsevier B.V. All rights reserved.