https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Facile synthesis of cerium oxide nanoparticles decorated flower-like bismuth molybdate for enhanced photocatalytic activity toward organic pollutant degradation https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:35936 in-situ precipitation of CeO₂ nanoparticles (size: ~26 nm) on the surface of flower-like Bi₂MoO₆ superstructures (diameter: 2.1-3.5 µm) by a simple method. The as-prepared photocatalysts were systematically characterized by a range of techniques. The photocatalytic degradation of rhodamine B (RhB) dye, methyl orange (MO) dye and tetracycline (TC) antibiotic by this novel photocatalyst was investigated under visible-light irradiation. The CeO₂/Bi₂MoO₆ heterojunction with a CeO₂/Bi₂MoO₆ weight ratio of 0.05 (0.05Ce-Bi) exhibited the highest photocatalytic activity with the RhB degradation efficiency of 100% in 75 min, which was considerably higher than those of pristine CeO₂ (26.8%) and Bi₂MoO₆ (80.3%) as well as their physical mixtures (74.8%). The more efficient separation of electron-hole pairs was identified as the primary reason of the enhanced photocatalytic activity. Moreover, the synthesized material maintained satisfactory activity even after 6 recycling runs, indicating its high photocatalytic stability. Therefore, our finding offers a new avenue for development of stable and efficient heterojunction photocatalysts for environmental purification.]]> Wed 01 Jul 2020 10:18:43 AEST ]]> Facile synthesis of flower-like Ag₃VO₄/Bi₂WO₆ heterojunction with enhanced visible-light photocatalytic activity https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34102 in-situ anchoring Ag₃VO₄ nanoparticles (size: ~21 nm) on the surface of Bi₂WO₆ microflowers (diameter: 2.5-4.5 µm) by a facile deposition route. The photocatalytic activity of these heterojunctions were studied by decomposing cationic dye rhodamine B (RhB), anionic dye methyl orange (MO) and neutral para-chlorophenol (4-CP) under visible light irradiation (λ > 400 nm). Among all the tested catalysts, the heterojunction with a Ag₃VO₄/Bi₂WO₆ molar ratio of 0.15/1 displays the maximum activity with the RhB degradation rate constant of up to 0.0392 min-1, a 6.7 or 1.7 times more enhancement compared with the pure Bi₂WO₆ or Ag₃VO₄. It is found that the introduction of Ag₃VO₄ is in favor of suppressing the electron-hole pair recombination of Bi₂WO₆, leading to an enhanced photocatalytic activity with good stability. The photogenerated holes (h⁺) and superoxide radicals (O·₂¯) play critical roles during the photocatalytic process. Ag₃VO₄/Bi₂WO₆ will have great potential in applications for environmental remediation due to the facile preparation method and superior photocatalytic activity.]]> Thu 07 Feb 2019 14:26:20 AEDT ]]>