Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-Dong, Nam-Gu, Pohang, Gyungbuk, Korea 790-784.
Langmuir. 2011 Aug 16;27(16):10243-50. doi: 10.1021/la201755w. Epub 2011 Jul 14.
We report a method for synthesizing three distinct type II 3D ZnO/ZnSe heterostructures through simple solution-based surface modification reactions in which polycrystalline ZnSe nanoparticles formed on the surfaces of single-crystalline ZnO building blocks of 3D superstructures. The experimental results suggested a possible formation mechanism for these heterostructures. The formation of the ZnO/ZnSe heterostructures was assumed to result from a dissolution-recrystallization mechanism. The optical properties of the 3D ZnO/ZnSe heterostructures were probed by UV-vis diffuse reflectance spectroscopy. The 3D ZnO/ZnSe heterostructures exhibited absorption in the visible spectral region. The visible photocatalytic activities of 3D ZnO/ZnSe heterostructures were much higher than those of the 3D pure ZnO structures. The activities of the 3D ZnO/ZnSe heterostructures varied according to the structures under visible light. The morphologies and exposed crystal faces of pure ZnO building blocks prior to surface modification had a significant effect on the visible light photocatalytic processes of ZnO/ZnSe heterostructures after surface modification.
我们报告了一种通过简单的基于溶液的表面改性反应合成三种不同类型的 II 型 3D ZnO/ZnSe 异质结构的方法，其中多晶 ZnSe 纳米粒子形成在单晶 ZnO 3D 超结构构建块的表面上。实验结果提出了这些异质结构的可能形成机制。ZnO/ZnSe 异质结构的形成被认为是由溶解-再结晶机制引起的。通过紫外-可见漫反射光谱研究了 3D ZnO/ZnSe 异质结构的光学性质。3D ZnO/ZnSe 异质结构在可见光谱区域表现出吸收。3D ZnO/ZnSe 异质结构的可见光光催化活性明显高于 3D 纯 ZnO 结构。3D ZnO/ZnSe 异质结构的活性根据可见光下的结构而变化。在表面改性之前，纯 ZnO 构建块的形貌和暴露的晶面对表面改性后 ZnO/ZnSe 异质结构的可见光光催化过程有显著影响。
