New Porous Visible Light Active Photocatalysts of MO_x-Titanate (M = Cr, Ni) Nanohybrids

Abstract:

We have synthesized for the first time efficient visible light active photocatalysts of porous MOx-Ti1.83O4 (M = Ni, Cr) heterostructure through an exfoliation-restacking route. XRD, SEM, TEM, and XAS results reveal that the titanate nanosheets and the nanosized metal oxide particles are well ordered in layer-by-layer way. N2 adsorption-desorption isotherm and diffuse UV-vis spectroscopic analyses demonstrate that the present nanohybrids have a large surface area (~190-240 m2/g) and a narrow bandgap (~1.6-2.4 eV), which are ascribable to the formation of porous structure and a coupling of the wide bandgap titanate and the narrow bandgap metal oxide species, respectively. These nanohybrids show an enhanced photocatalytic activity to effectively decompose organic compounds under the irradiation of visible light. The present results highlight that the exfoliation-restacking route can provide a very powerful way of developing novel heterostructured materials with efficient visible light driven photocatalytic activity.

• Periodical: Advances in Science and Technology (Volume 45)
• Pages: 779-786
• DOI: https://doi.org/10.4028/www.scientific.net/AST.45.779
• Online since: October 2006
• Authors: S.J. Hwang, T.W. Kim
• Keywords: Bandgap Engineering, Exfoliation-Restacking, Heterostructure, Nanohybrid, Visible Active Photocatalysts

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