1. Key Laboratory of Systems Bioengineering of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China 2. School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China 3. Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China 4. Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
In recent years, much effort has been focused on the development of the photocatalysts with high performance under visible light irradiation. In this paper, three-dimensional porous La-doped SrTiO3 (LST) microspheres were prepared by a modified sol–gel method, in which the agarose gel/SrCO3 microsphere and La2O3 were employed as the template and the La resource, respectively. The as-prepared LST microspheres exhibit a porous structure with a diameter of about 10 µm and a surface pore size of about 100 nm. The La element was doped into the crystal lattice of SrTiO3 by the substitution of La3+ for Sr2+. Therefore, the absorption edge of LST samples shifts toward the visible light region, and their photocatalytic activity for the Cr(VI) reduction is enhanced under visible light. Among all LST samples, LST-0.5 (the La3+ doping content is 0.5 wt-%) exhibited the highest visible-light photocatalytic activity, which can reduce 84% Cr(VI) within 100 min. This LST materials may become a promising photocatalyst for the facile treatment of wastewater containing poisonous heavy metal ions.
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