Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-Dong, Nam-Gu, Pohang, Gyungbuk, Korea.
Nanoscale. 2012 Mar 21;4(6):2066-71. doi: 10.1039/c2nr11869f. Epub 2012 Feb 16.
We report the synthesis of porous ZnO-ZnSe nanocomposites for use in visible light photocatalysis. Porous ZnO nanostructures were synthesized by a microwave-assisted hydrothermal reaction then converted into porous ZnO-ZnSe nanocomposites by a microwave-assisted dissolution-recrystallization process using an aqueous solution containing selenium ions. ZnO and ZnSe nanocrystallites of the nanocomposites were well-mixed (rather than forming simple core-shell (ZnO-ZnSe) structures), particularly, in the outer regions. Both ZnO and ZnSe were present at the surface and exposed to the environment. The porous ZnO-ZnSe nanocomposites showed absorption bands in the visible region as well as in the UV region. The porous ZnO-ZnSe nanocomposites had much higher activities than the porous ZnO nanostructures. Control experiments using cutoff filters revealed that the main photocatalytic activity of the synthesized nanostructures arose from photo-excitation of the semiconductor (ZnO or ZnSe) via absorption of light of an energy equal to or exceeding the band gap energy.
我们报告了多孔 ZnO-ZnSe 纳米复合材料的合成，用于可见光光催化。通过微波辅助水热反应合成多孔 ZnO 纳米结构，然后通过微波辅助溶解-再结晶过程，使用含有硒离子的水溶液将其转化为多孔 ZnO-ZnSe 纳米复合材料。纳米复合材料中的 ZnO 和 ZnSe 纳米晶很好地混合（而不是形成简单的核壳（ZnO-ZnSe）结构），特别是在外部区域。ZnO 和 ZnSe 都存在于表面并暴露于环境中。多孔 ZnO-ZnSe 纳米复合材料在可见区域和紫外区域都显示出吸收带。多孔 ZnO-ZnSe 纳米复合材料的活性比多孔 ZnO 纳米结构高得多。使用截止滤光片进行的对照实验表明，所合成的纳米结构的主要光催化活性源于半导体（ZnO 或 ZnSe）通过吸收等于或超过带隙能的光的光激发。
