Heterojunction of FeOOH and TiO2for the Formation of Visible Light Photocatalyst

Abstract

FeOOH/<TEX>$TiO_2$</TEX>, a heterojunction structure between FeOOH and <TEX>$TiO_2$</TEX>, was prepared by covering the surface of the <TEX>$\sim$</TEX>100-nm-sized FeOOH particles with Degussa P25 by applying maleic acid as an organic linker. Under visible light irradiation (<TEX>${\lambda}{\geq}$</TEX> 420 nm), FeOOH/<TEX>$TiO_2$</TEX> showed a notable photocatalytic activity in removal of gaseous 2-propanol and evolution of <TEX>$CO_2$</TEX>. It was found that FeOOH reveals a profound absorption in the spectral range of 400 - 550 nm, and its valence band (VB) level is located relatively lower than that of <TEX>$TiO_2$</TEX>. The considerable photocatalytic efficiency of the FeOOH/<TEX>$TiO_2$</TEX> under visible light irradiation was therefore deduced to be caused by the hole transfer between the VB of FeOOH and <TEX>$TiO_2$</TEX>.