https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 Facile synthesis of cerium oxide nanoparticles decorated flower-like bismuth molybdate for enhanced photocatalytic activity toward organic pollutant degradation https://nova.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 ]]> Synthesis of n-type TaON microspheres decorated by p-type Ag₂O with enhanced visible light photocatalytic activity https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:34836 in situ growth of Ag₂O nanoparticles (size: ~12 nm) on their surfaces was realized by a simple deposition method. All Ag₂O/TaON heterojunctions were much more active than pristine TaON or a mechanical mixture of Ag₂O and TaON in the degradation of organic pollutants (cationic dye rhodamine B, anionic dye methyl orange and neutral para-chlorophenol) under visible light (λ > 400 nm). Significantly, the highest photocatalytic activity was observed in the heterojunction with a Ag/Ta molar ratio of 0.1/1 (0.1Ag-Ta). The RhB degradation rate constant using 0.1Ag-Ta is approximately 9.7 and 3.1 times higher than those obtained by using TaON microspheres, and the mechanical mixture, respectively. The superior photocatalytic performance of Ag₂O/TaON is ascribed to the hierarchical superstructure and efficient charge separation. The mainly involved active species (holes and superoxide radicals) were identified via radical trapping experiments and electron paramagnetic resonance spectroscopy. The results demonstrate that Ag₂O/TaON is a potential VLD photocatalyst for wastewater treatment.]]> Thu 16 May 2019 14:08:57 AEST ]]> Facile synthesis of flower-like Ag₃VO₄/Bi₂WO₆ heterojunction with enhanced visible-light photocatalytic activity https://nova.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 ]]> A novel heterostructure of BiOI nanosheets anchored onto MWCNTs with excellent visible-light photocatalytic activity https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:29921 Fri 24 Aug 2018 09:00:42 AEST ]]>