Controllable synthesis of CaTi2O4(OH)2 nanoflakes by a facile template-free process and its properties

Serrated leaf-like CaTi2O4(OH)2 nanoflake crystals were synthesized via a template-free and surfactant-free hydrothermal process. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The growth process for CaTi2O4(OH)2 nanoflakes was dominated by a crystallization–dissolution–recrystallization growth mechanism. BET analysis showed that CaTi2O4(OH)2 nanoflakes had mesoporous structure with an average pore size of 8.7 nm, and a large surface area of 88.4 m2 g−1. Cyclic voltammetry and galvanostatic charge–discharge tests revealed that the electrode synthesized from CaTi2O4(OH)2 nanoflakes reached specific capacitances of 162 F g−1 at the discharge current of 2 mA cm−2, and also exhibited excellent electrochemical stability.