A facile and high-yield approach to synthesize one-dimensional CeO2 nanotubes with well-shaped hollow interior as a photocatalyst for degradation of toxic pollutants

A facile, template-free and high-yield synthesis of single-crystalline cerium dioxide nanotubes (CeO2-NT) has been reported via a casually-modified approach based on the hydrothermal treatment of Ce(OH)CO3 precursors with alkali solution in an aqueous phase. This simple modification in synthesis procedures not only improves the yield of CeO2-NT remarkably, but also gives rise to the formation of CeO2-NT featuring excellent nanotubular open-ended structure with a well-shaped hollow interior. The collection techniques of BET, UV/visible diffuse reflectance spectra (DRS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis have been employed to characterize the morphology and optical properties of the as-prepared CeO2-NT. Significantly, we demonstrate that CeO2-NT exhibits a markedly enhanced photocatalytic activity and stability as compared with its counterpart of CeO2 nanoparticles and commercial TiO2 (P25) toward the degradation of aromatic benzene, a well-known toxic pollutant that commonly occurs in urban ambient air and is of significant concern regarding environmental health because of its toxic, mutagenic, or carcinogenic properties. This represents a first example to demonstrate the advantage of CeO2 nanotubes as photocatalyst as compared to its counterpart of CeO2 nanoparticles, clearly suggesting the morphology/shape-dependent photocatalytic behaviour of CeO2 materials. Therefore, our current work not only offers a simple approach for fabrication of open-ended CeO2-NT with well-shaped hollow interior, but also demonstrates the promising potential of the applications of CeO2-NT, CeO2-NT-based and other metal oxide nanotube-based materials in the area of photocatalysis, which will inevitably enrich the intriguing chemistry of morphology/shape-dependent heterogeneous photocatalysis and thermal catalysis.