화학공학소재연구정보센터
Applied Surface Science, Vol.414, 277-291, 2017
Effects of phosphorus-doping on energy band-gap, structural, surface, and photocatalytic characteristics of emulsion-based sol-gel derived TiO2 nano-powder
Different amounts of phosphorus (P)-doped TiO2 (PDT) nano-powders (P = 0-10 wt.%) were synthesized by following a new emulsion-based sol-gel (EBSG) route and calcined at 400 degrees C-800 degrees C for 6h. These calcined PDT powders were then thoroughly characterized by means of XRD, XPS, SEM, FT-IR, FT-Raman, DRS, BET surface area, zeta-potential, cyclic-voltammetry and photocatalytic evaluation using methylene blue (MB) as a model-pollutant and established the effects of phosphorous doping on structural, surface, band-gap energy, and photocatalytic characteristics of TiO2 nano-powder formed in EBSG route. The characterization results suggest that the EBSG derived TiO2 nano-powder after calcination at 400 degrees C for 6 his in the form of anatase phase when it was doped with <8 wt.% P, and it is in the amorphous state when doped with >8 wt.% P. Furthermore, these EBSG derived PDT powders own high negative zeta-potentials, high specific surface areas (up to >250 m(2)/g), and suitable band-gap energies (<3.34 eV). Surprisingly, these PDT powders exhibit very high MB adsorption (up to 50%) from its aqueous 0.01 mM, 0.02 mM and 0.03 mM solutions during 30 min stirring in the dark, whereas, the commercial Degussa P-25 TiO2 nano-powder shows no adsorption. Among various photocatalysts investigated in this study, the 1 wt.% P-doped TiO2 nano-powder formed in EBSG route exhibited the highest photocatalytic activity for MB degradation reaction. (C) 2017 Elsevier B.V. All rights reserved.