Fluorescence Properties of the Lanthanide Supported onto Titanate Nanosheets

Abstract

Metal oxide nanosheets are increasingly used as catalysts, hard coatings and transparent thin films. Among these materials, TNSs (Titanate Nanosheets) synthesized in liquid phase enjoy particular attention due to their water dispersibility, photocatalytic activity, unique morphology and ease of synthesis. Importantly, the photo-induced redox reaction between TNSs and metal oxides affords potentially fluorescent metal-supported TNSs with enhanced photocatalytic activity, e.g., Ln/TNSs (Lanthaide-supported TNSs). Herein, TNSs doped with arbitrary amounts of group 5 elements (M-TNSs: M = V, Nb and Ta) were prepared to investigate the fluorescent excitation spectra of Ln/M-TNSs and thus shed light on the mechanism of photodeposition and determine the origin of Ln/TNS fluorescence. As a result, photodepositiom was shown to involve phot-induced redox reaction between TNSs and lanthanide oxides, and the fluorescence intensity of Ln/TNSs and Ln/M-TNSs was demonstrated to be determined by the overlap of TNS and Ln 3+ excitation energies.