Polymorphous ZnO Nanostructures: Zn Polar Surface-Guided Size and Shape Evolution Mechanism and Enhanced Photocatalytic Activity
Polymorphous ZnO Nanostructures: Zn Polar Surface-Guided Size and Shape Evolution Mechanism and Enhanced Photocatalytic Activity
复制标题
多晶型 ZnO 纳米结构：Zn 极性表面引导的尺寸和形状演化机制以及增强的光催化活性
DOI：
10.1002/cctc.201700135
复制
发表时间：
2017
期刊：
影响因子：
4.5
通讯作者：
Tong Guoxiu
中科院分区：
文献类型：
--
作者：
Zhao Yanting;Cui Tingting;Wu Tong;Jin Chen;Qiao Ru;Qian Yao;Tong Guoxiu
本研究提出了一种简单的低温化学蚀刻方法，用于选择性制备单分散的六方单晶ZnO纳米结构。从纳米片（NPs）到纳米密封（NS）、纳米碗（NB）和纳米环（NR）的形态演化是由带正电荷的（0 0 0 1）Zn极性表面引发的，并由最小能量原理驱动。通过考察ZnO的极性面、比表面积、能带、缺陷、光学性质以及对罗丹明B降解的催化活性，确定了ZnO的形貌、尺寸和功能之间的关系。 由于增强的光捕获和等离子体共振增强的吸收，ZnO NB和ZnO NR表现出改善的光催化性能。对于小尺寸和低温下形成的ZnO纳米带，表面复合对表观速率常数k起着关键作用。在高反应温度下形成的ZnO NB的光催化活性随着尺寸的增加而降低，因为表面积减小。
This study proposes a simple, low‐temperature chemical etching method for selective preparation of monodispersed, hexagonal, single‐crystal ZnO nanostructures. The morphological evolution from nanoplates (NPs) to nanoseals (NSs), nanobowls (NBs), and nanorings (NRs) is initiated by positively charged (0 0 0 1) Zn polar surface and driven by the principle of minimum energy. The relationship among the morphology, dimensions, and function of ZnO was determined by investigating polar planes, surface areas, energy bands, defects, optical properties, and catalytic activity for rhodamine B degradation. The ZnO NBs and ZnO NRs exhibit improved photocatalytic performance because of enhanced light harvesting and plasmonic resonance enhanced absorption. Surface recombination plays a key role in the apparent rate constantkfor ZnO NBs with small size and those formed at low reaction temperatures. The photocatalytic activity of ZnO NBs formed at high reaction temperatures decreases with increasing size because of the decreased surface area.