Non-fluorinated synthesis of anatase TiO2 with dominant {001} facets: influence of faceted structures on formaldehyde sensitivity

Abstract

Titanium dioxide (TiO₂), the most widely investigated metal oxide due to its extraordinary surface, electronic and catalytic properties, is better manifested with exposed {001} facets. This article delineates the room temperature synthesis of TiO₂ with 90% exposed {001} facets without using any fluorine containing precursor or hazardous material. Cetyltrimethylammonium bromide (CTAB) is explored as a capping agent to suppress the growth of the thermodynamically stable (101) plane. The {001} faceted nanosheets are decorated with gold nanoparticles of mean diameter 10 nm. The materials are characterized using XRD, TEM, XPS, as well as UV-vis, Raman and photoluminescence spectroscopy. The surface reactivities of different facets of TiO₂ are substantiated in the light of formaldehyde (HCHO) oxidation. The synergistic effect between the reactive {001} facet of TiO₂ and gold nanoparticles towards the photocatalysis of HCHO is also investigated and corroborated using mass spectroscopy.