Facile synthesis of ZnO/Zn₂TiO₄ core/shell nanowires for photocatalytic oxidation of acetone

ZnO/Zn₂TiO₄ core/shell nanowires were synthesized for the first time based on a solid-solid reaction of ZnO nanowires with a conformal shell of TiO₂, which was deposited by a sol-gel method. The as-prepared samples were characterized by X-ray diffraction (XRD) analysis, transmission electron microscope (TEM) and environmental scanning electron microscope (ESEM). The surface photovoltage (SPV) spectra indicated that the as-synthesized ZnO/Zn₂TiO₄ core/shell nanowires exhibited more excellent photovoltaic activity than single ZnO nanowires. The enhanced photocatalytic activity of the ZnO/Zn₂TiO₄ core/shell nanowires was demonstrated by the degradation of acetone under UV light irradiation. As monitored by the in situ FTIR, a sequence of chemical steps could be extracted during the photocatalytic oxidation of gaseous acetone, which was firstly degraded into formate, and subsequently converted into CO and CO₂. CO₂ was partially converted to carbonate further. © 2010 Elsevier B.V.