Study on effects of tungstophosphate structures on electrochemically induced luminescence switching behaviors of the composite films consisting of tris(1,10-phenanthroline) ruthenium

Abstract

For exploration of the effects of tungstophosphate structures on electrochemically induced fluorescence switchable behaviors, four composite films consisting of tris(1,10-phenanthroline) ruthenium (Ruphen) and tungstophosphates with different structures (PW: [PW₁₂O₄₀]³⁻ (PW₁₂), [P₂W₁₈O₆₂]⁶⁻ (P₂W₁₈), [NaP₅W₃₀O₁₁₀]¹⁴⁻ (P₅W₃₀), and [H₇P₈W₄₈O₁₈₄]³³⁻ (P₈W₄₈)) were prepared by the layer-by-layer self-assembly method under identical conditions. The composite films were characterized by cyclic voltammetry, UV-vis spectroscopy, X-ray photoelectron spectroscopy, fluorescence spectroscopy and atomic force microscopy. In situ fluorescence spectroelectrochemical measurements display that the fluorescence quenching efficiencies of the four composite films under electrochemical stimulation depend on the tungstophosphate structures, demonstrating that the desired electrochemically induced fluorescent switchable materials can be optimized by the choice of different polyoxometalates.