WO3-decorated ZnO nanostructures for light-activated applications

Abstract

In the present work, a two-step vapor-phase route was implemented for the tailored design of ZnO–WO₃ nanoheterostructures supported on fluorine-doped tin oxide (FTO) substrates. Under optimized conditions, the sequential use of chemical vapor deposition (CVD) and radio frequency (RF)-sputtering for the deposition of zinc and tungsten oxides respectively, resulted in the growth of calyx-like ZnO nanostructures uniformly decorated by a conformal dispersion of low-sized WO₃ nanoparticles. The target materials were characterized by means of a multi-technique approach, with particular regard to their structural, compositional, morphological and optical properties. Finally, their photocatalytic performances were preliminarily tested in the abatement of NO_X gases (NO and NO₂). Due to the unique porous morphology of the ZnO nanodeposit and the high density of ZnO–WO₃ heterojunctions, WO₃-decorated ZnO revealed appealing De-NO_X characteristics in terms of both degradation efficiency and selectivity. Such features, along with the photoinduced superhydrophilicity and self-cleaning properties of the present nanomaterials, candidate them as promising functional platforms for applications in smart windows and building materials for environmental remediation.