A robust photocatalyst using silver quantum clusters grafted in titanium dioxide nanotubes

Abstract

Enhanced photocatalytic activity resulting from the direct electron transfer from noble metal nanoparticles coupled with semiconductor nanostructures is well reported. However, studies on the photocatalytic activity of semiconductor nanostructures coupled with noble metal clusters that exhibit fascinating chemical, optical, and electronic properties are still limited. In this context, we herein report the fabrication of silver quantum clusters grafted on titanium dioxide nanotubes (AgQCs-TNT) towards the photodegradation of ibuprofen and photoreduction of hexavalent chromium ions under visible light irradiation. The structural, chemical, morphological, and optical properties of the as-synthesized samples were studied through X-ray diffraction, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and UV-visible diffuse reflectance spectroscopy. Interestingly, AgQCs-TNT exhibited excellent photocatalytic efficiency in the degradation of ibuprofen and the reduction of hexavalent chromium ions under visible light irradiation in comparison to their pristine counterparts. Role of scavengers and plausible mechanisms pertaining to the improved photocatalytic activity of AgQCs-TNT due to the synergy between the pristine counterparts are discussed.