Improved photocatalytic activity of TiO2 produced by an alcohothermal approach through in-situ decomposition of NH4HCO3

Abstract High crystallinity of TiO 2 was prepared by a modified alcohothermal method, in which titanium isopropoxide was used as the titania precursor, absolute ethanol as the reaction medium, and NH 4 HCO 3 as the raw materials for release of water, ammonia and carbon dioxides via in-situ decomposition. The X-ray powder diffraction (XRD) and transmission electron microscope (TEM) measurements showed that water and ammonia from the in-situ decomposition of NH 4 HCO 3 played an important role in conducting the size, shape, crystallinity and microstructure of TiO 2 . The photoluminescence spectroscopy and photocurrent measurements indicated that enhanced crystallinity could hinder the recombination and promote the separation of electron-hole pairs in TiO 2 , which contribute to the improvement of photocatalytic activity. Methyl orange photodegradation under UV light confirmed that high crystallinity of TiO 2 did present a high photocatalytic activity due to the effective separation of photoinduced charges.