Simple Ethanol Impregnation Treatment Can Enhance Photocatalytic Activity of TiO₂ Nanoparticles under Visible-Light Irradiation

Doping with impurities as well as introducing oxygen vacancies has been recognized as an important means to enhance photocatalytic activity of TiO₂ under visible-light irradiation. Here we report that simple ethanol impregnation followed with mild heat treatment (150–400 °C) can color TiO₂ nanoparticles and enhance visible-light photocatalytic activity of the material. The coloration and photocatalytic activity for β-naphthol and rhodamine B (RhB) degradation were observed to be dependent on heat-treatment temperature, and the highest activity as well as the most coloration was obtained at temperatures around 200 to 250 °C. Comprehensive analyses based on X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) investigations as well as first-principle density functional calculation suggest that the simple ethanol impregnation treatment leads to the generation of oxygen vacancy on TiO₂ surface which should be responsible for the coloration and enhanced photocatalytic activity

Urine formaldehyde level is inversely correlated to mini mental state examination scores in senile dementia

It is widely known that exogenous formaldehyde exposure induces human cognitive impairment and animal memory loss; and recent studies show that formaldehyde at pathological levels induces A beta deposition and misfolding of tau protein to form globular amyloid-like aggregates. Endogenous formaldehyde may be a marker for progressive senile dementia