Polydopamine-coated tungsten oxide (PDA@WO3) nanomateri-al is synthesized by the polymerization of dopamine around the surface of WO3 to form the perfect yolk-shell structures, and the optoelectronic properties and photocatalytic performance in the wide pH range are studied. After coating of PDA around the WO3 surface, as-obtained PDA@WO3 possesses better light absorption, lower band gap, stronger photocurrent response, and lower resistance than pristine WO3. As a result, the improved photocatalytic ability of PDA@WO3 nanocompo-sites, by optimizing the amount of dopamine, is achieved. Compared with pristine WO3, PDA@WO3 exhibits better photocatalytic activity, and the degradation rate of methyl blue reaches 80.2% (pH = 5.4) and 94.5% (pH = 7.2) after 150 min. Combined band energy with trapping experiments of the active substance, photocatalytic activity and degradation mechanism are discussed. Originated from the π electron conjugation system of PDA and yolk-shell structure of PDA@WO3, the mobility of photogenerated electrons increase and the recombination of electrons-holes reduce that result in improvement of the photocatalytic performance of pristine WO3, implying surface-modified metal oxide with yolk-shell is a potential photocatalytic material for degradation in wide pH range.
展开▼
