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Metastable h-MoO 3 hexagonal prisms have been fabricated through a simple green ultrasonic-assisted chemical route. After calcination at 440 C for 2 h, the thermodynamically stable a-MoO 3 nanoplate-based rods have been achieved through a process of in situ phase transformation. The as-synthesised products have been characterised by powder X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectrum, UVÀvis diffuse reflection spectroscopy and photoluminescence spectroscopy. The phase transformation from metastable h-MoO 3 to stable a-MoO 3 is observed at 419 C according to the differential scanning calorimetry results. The possible growth mechanism of MoO 3 crystals has been proposed based on the experimental results. The prepared two kinds of MoO 3 samples both display higher photocatalytic performance for degrading rhodamine B compared to that of commercial MoO 3 . In the present system, a-MoO 3 nanoplate-based rods exhibit slightly higher degradation activity than h-MoO 3 hexagonal prisms, which is possibly due to its smaller band gap energy, smaller scale of nanoplate, better adsorption capacity and lower recombination of photogenerated electrons and holes.

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Arrayed β‐Bi2O3 nanotubes (NTs) were synthesized for the first time through a rational “self‐sacrificing template” route, simply by oxidizing the precursor metallic bismuth NT arrays in air at 200−220 °C for 14−18 h. XRD, TEM, and HRTEM characterizations show that the prepared β‐Bi2O3 samples are all phase pure and the β‐Bi2O3 NTs have uniform diameters of approximately 3−6 nm and lengths up to several micrometers. The optical absorption and photoluminescence (PL) characteristics of the prepared samples were investigated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

A room-temperature aqueous-chemical route has been developed to synthesize a high proportion (above 80%) of bamboo-raft-like bismuth nanotube arrays using bismuth chloride and metallic zinc powder as reagents. The prepared Bi nanotubes have uniform diameters of approximately 3−5 nm and lengths from several hundred nanometers to several mi-

Hollow CuS architectures have been fabricated via a template-free and green sonochemical process displaying superior Fenton-like catalytic activities.