Effect of CeO2 content in morphology and optoelectronic properties of TiO2-CeO2 nanoparticles in visible light organic degradation
Effect of CeO2 content in morphology and optoelectronic properties of TiO2-CeO2 nanoparticles in visible light organic degradation
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DOI：
10.1016/j.mssp.2018.10.017
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发表时间：
2019-02-01
影响因子：
4.1
通讯作者：
Alvarez-Lainez, Monica
中科院分区：
文献类型：
--
作者：
Carolina Cano-Franco, Julieth;Alvarez-Lainez, Monica
TiO 2是一种半导体材料，由于其带隙能量，被广泛应用于有机污染物的光催化降解。然而，其吸收范围仅限于紫外辐射，其小于太阳光的10%。为了增加TiO 2纳米颗粒上的吸附面积，使用改进的溶胶-凝胶方法来产生更小的颗粒尺寸，并将吸收范围扩展到可见光谱，合成具有不同CeO 2含量的TiO 2纳米颗粒，以在它们之间产生半导体异质结。这些TiO 2-CeO 2纳米粒子的晶体学，形态学和光电特性进行了研究，并区分两个晶相：TiO 2和CeO 2的萤石。CeO 2含量的增加产生的微晶尺寸在6.5 nm和12.0 nm之间。TiO 2-CeO 2纳米粒子显示出的形态学特性，如小的粒径，非均匀的表面和高的BET比表面积相比，裸露的商业TiO 2。这些特征涉及CeO 2在TiO 2纳米颗粒表面的积极作用，因此TiO 2-CeO 2纳米颗粒表现出由有效带隙减小和电磁光谱红移引起的增强的光电性能。亚甲基蓝降解实验表明，TiO 2-CeO 2纳米粒子在可见光下具有较高的光催化活性。
TiO2 is a semiconductor widely used in photocatalytic degradation of organic pollutants due to its band gap energy. However, its absorption range is restricted only to UV radiation that is less than 10% of solar light With the aim of increasing the adsorption area on TiO2 nanoparticles a modified sol-gel method was used to produce a smaller particle size, and to extend the absorption range to the visible spectrum, TiO2 nanoparticles were synthesized with different CeO2 contents to generate semiconductor heterojunction between them. The crystallographic, morphological, and optoelectronic characteristics of these TiO2-CeO2 nanoparticles were studied, and two crystalline phases were differentiated: anatase for TiO2 and fluorite for CeO2. An increase in the CeO2 content produced crystallite sizes between 6.5 nm and 12.0 nm. TiO2-CeO2 nanoparticles showed morphological properties such as small particle size, heterogeneous surface and high BET surface area compared to bare commercial TiO2. These features involve a positive effect of CeO2 in TiO2 nanoparticles surface, thus TiO2-CeO2 nanoparticles exhibit enhanced optoelectronic properties caused by a decrease in the effective band gap and red-shift in the electromagnetic spectrum. In addition, methylene blue degradation showed that TiO2-CeO2 nano-particles are suitable for high photocatalytic activity application under visible light.