Cr-doped TiO2 ( Cr-TiO2 ) microspheres with a high percentage of exposed ( 001 ) facet were pre-pared by a one-step hydrothermal treatment. The morphology, crystal structure and photo-absorption property of the obtained samples were characterized by field emission scanning electron microscopy ( FESEM ), trans-mission electron microscopy(TEM), X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS), etc. The results demonstrated that Cr3+ ion and CrO3 cluster coexisted in the catalysts. Cr3+ was incorporated into the crystal lattice of anatase TiO2, which resulted in the Cr3+→Ti4+ charge transfer so that Cr-TiO2 had strong absorption in the visible region. The corrosive effect of generated HF was weakened by doping small amount of Cr, which benefited for the formation of smooth exposed (001) facets in the Cr-TiO2 samples. The visible-light-driven photocatalytic properties of the samples were studied by the degradation of Acid Red 88 dye. The Cr-TiO2 microsphere with high exposure of (001) facet exhibited much higher efficiency than the traditional Cr-TiO2 without exposed ( 001 ) facet. Such doped TiO2 catalysts with definite surface micro-structure will be helpful for preparing TiO2-based photocatalysts suitable for practical applications.%采用一步水热法制备了具有高裸露率(001)晶面的锐钛矿相Cr掺杂TiO2( Cr-TiO2)微球，利用场发射扫描电子显微镜( FESEM)、透射电子显微镜( TEM)、X射线衍射仪( XRD)和X射线光电子能谱仪( XPS)等对样品进行了表征.结果表明，掺杂的Cr元素以Cr3+离子和CrO3团簇2种形式存在， Cr3+离子进入TiO2晶格，形成Cr3+→Ti4+电荷转移跃迁， Cr-TiO2在可见光区具有强烈吸收.少量的Cr掺杂有利于形成平整的高活性(001)晶面.以可见光降解酸性红染料作为探针反应研究了Cr-TiO2的催化活性.结果表明，具有(001)晶面的Cr-TiO2的催化效率明显优于普通的Cr-TiO2.
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