Urea-based hydrothermal growth, optical and photocatalytic properties of single-crystalline In(OH)3 nanocubes

Nearly monodisperse single-crystalline In(OH)(3) nanocubes were successfully synthesized using In(NO(3))(3) x 4.5 H(2)O as indium source in the presence of urea and cetyltrimethyl ammonium bromide (CTAB) by a two-step hydrothermal process: the stock solution was heated at 70 degrees C for 24 h and then at 120 degrees C for 12 h. The structure and morphology of the resultant In(OH)(3) samples were determined by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results revealed that most of as-synthesized In(OH)(3) nanocubes were uniform in size, with the average edge length of approximately 700 nm. The influences of the reaction temperature, the reaction time, the mineralizer, and the surfactant on the morphology of the obtained products were discussed in detail. Room-temperature photoluminescence (PL) spectrum of the In(OH)(3) nanocubes showed a peculiar strong emission peak centered at 480 nm. Furthermore, the photocatalytic properties of the In(OH)(3) nanocubes were tested. It was found that In(OH)(3) exhibited not only higher activity for benzene removal, but also better H(2) evolution from water than the commercial Degussa P25 TiO(2).