State Key Laboratory of Silicon Materials, & Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, PR China.
ACS Appl Mater Interfaces. 2012 Sep 26;4(9):4800-6. doi: 10.1021/am3011516. Epub 2012 Aug 23.
Various semiconductors have been studied as photocatalysts for photocatalytic degradation of pollutants in aqueous solutions. As one of the promising visible-light-driven semiconductor photocatalysts, α-Fe(2)O(3) has advantages of low cost and stability. However, its application is inhibited by the poor separation of photogenerated electron-hole pair. In this work, hybrid structures were prepared to improve the performance of α-Fe(2)O(3). CdS nanoparticles were overgrown on the preformed single-crystalline α-Fe(2)O(3) nanorods by a simple and mild one-step wet-chemical method, resulting in α-Fe(2)O(3)/CdS cornlike nanocomposites. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy showed the α-Fe(2)O(3)/CdS core/shell heterostructure of the nanocomposite with high crystallinity. Furthermore, the cornlike nanocomposites exhibited superior photocatalytic performances under visible light irradiation over the pure α-Fe(2)O(3) nanorods and CdS nanoparticles. The photocatalytic activity of the composites is superior to the previously-reported pure α-Fe(2)O(3) nanomaterials, and the performance is comparable to both the commercial TiO(2) (P25) which is used under UV irradiation and the newly developed α-Fe(2)O(3)/SnO(2) photocatalyst under visible light irradiation. The enhanced performance is associated with the larger surface area of the cornlike structure, the crystalline nature of the materials and the synergy in light absorption and charge separation between α-Fe(2)O(3) and CdS. As such, our α-Fe(2)O(3)/CdS cornlike nanocomposites may be promising to be used as visible-light-driven high-performance photocatalyst.
各种半导体已被研究作为光催化剂用于光催化降解水溶液中的污染物。α-Fe(2)O(3)作为一种有前途的可见光驱动半导体光催化剂,具有成本低和稳定性好的优点。然而,其应用受到光生电子-空穴对分离效果差的限制。在这项工作中,制备了混合结构以提高 α-Fe(2)O(3)的性能。通过简单温和的一步湿化学法,在预先形成的单晶 α-Fe(2)O(3)纳米棒上生长了 CdS 纳米粒子,得到了 α-Fe(2)O(3)/CdS 玉米状纳米复合材料。X 射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和拉曼光谱表明该纳米复合材料具有高结晶度的 α-Fe(2)O(3)/CdS 核/壳异质结构。此外,玉米状纳米复合材料在可见光照射下表现出比纯 α-Fe(2)O(3)纳米棒和 CdS 纳米粒子更高的光催化性能。该复合材料的光催化活性优于之前报道的纯 α-Fe(2)O(3)纳米材料,且与商用 TiO(2)(P25)(在 UV 照射下使用)和新开发的 α-Fe(2)O(3)/SnO(2)光催化剂(在可见光照射下使用)相当。性能的提高与玉米状结构的较大表面积、材料的结晶性质以及 α-Fe(2)O(3)和 CdS 之间的光吸收和电荷分离协同作用有关。因此,我们的 α-Fe(2)O(3)/CdS 玉米状纳米复合材料有望成为可见光驱动的高性能光催化剂。