Synthesis of radially aligned nano-rutile modified with Au and Ni for the photodegradation of methyl orange

Resin-gel incorporation of high concentrations of W6+ and Zn2+ into TiO2-anatase crystal to form quaternary mixed-metal oxides: effect on the a lattice parameter and photodegradation efficiency

“…The photoactivity of TiO 2 has been shown to be reliant on its surface and crystal properties; these include morphology, surface area, polymorphic phase, lattice defects, the extent of crystallinity, particle size, the presence of uncoordinated surface sites and exposed crystal facets among other things. [2][3][4][5][6][7] For instance, Thuy-Duong and co-workers demonstrated the photodegradation of methylene blue had a strong dependency on the TiO 2 morphology; TiO 2 in the shape of a ower containing rutile nano-prisms adhered by anatase nanoparticles showed the best photodegradation efficiency whereas the material with a hierarchical cauliower morphology had the least photoactivity. 8 In another study, He et al demonstrated how the morphology of TiO 2 , its crystal size, and calcination progress affected the photodegradation of gaseous benzene.…”

“…21,22 Dziike et al reported that the photocatalytic activity of TiO 2 was increased by loading Ni nanoparticles onto it and attributed the increase in activity to the separation of the active charge carriers. 3 This occurs because the Fermi level of TiO 2 is higher than that of most of the metal nanoparticles commonly used for this purpose, so the electrons migrate from TiO 2 to the metal nanoparticles resulting in a space charge layer at the boundaries between TiO 2 and the metal nanoparticles. The electric eld created drives the electrons to the inside and the holes are drawn to the interfacial region of TiO 2 .…”

“…3,16,[24][25][26][27] Additionally, when noble metals are dispersed on the surface of TiO 2 a plasmonic composite can be formed that allows the material to be able to absorb visible light by surface plasmon resonance (SPR). 3,16,[28][29][30] Other 33,34 Here, the enhanced activity was due to the electron band positions of WO 3 and TiO 2 having been favorably positioned for charge separation. The photoactivity of TiO 2 /WO 3 composites have also been measured under visible radiation, as the bandgap of WO 3 is narrower (2.8 eV), and was shown to be superior to that of individual WO 3 and TiO 2 under visible light.…”

Recovery of waste gold for the synthesis of gold nanoparticles supported on radially aligned nanorutile: the growth of carbon nanomaterials

“…In this regard, we have endeavoured to recover gold from waste tailings. Apart from its use in jewellery, gold is a very useful material, particularly in its nano form, in biological systems, 2,3 heterogeneous catalysis, 4,5 plasmonics, 6,7 analytical sensors 8-10 and devices'. 11,12 In heterogeneous catalysis, gold nanoparticles are more useful when supported on other materials in a way that increases (i) the surface area of the active, (ii) stability and (iii) dispersion of the particles over a large surface area.…”

Synthesis and characterization of polyaniline, polypyrrole and zero-valent iron-based materials for the adsorptive and oxidative removal of bisphenol-A from aqueous solution

“…31,32 This is because Fe 0 activates oxidants such as hydrogen peroxide (H 2 O 2 ) and persulphate (S 2 O 8 2À ) to form highly reactive (oxidizing) radicals such as hydroxyl (HOc), sulfate (SO 4 c À ) and superoxide (O 2 c À ) radical species which are known to be highly effective for degrading organic contaminants. 31,32 Other materials which undergo AOPs and have been exploited for water remediation include titanium dioxide and its derivatives, 33,34 Liu et al also demonstrated the removal of over 75% of BPA within 12 hours using a zero valent aluminum-acid system. 31 The high efficiencies of AOPs in the removal of BPA from water have motivated the synthesis of a dual nanocomposite, where it was postulated that polypyrrole-polyaniline would adsorb BPA and Fe 0 would degrade BPA into less-toxic degradation products.…”