Yang Shuo, Wang Lijing, Yan Yongsheng, Yang Lili, Li Xin, Lu Ziyang, Zhai Hongju, Han Donglai, Huo Pengwei
School of Chemistry & Chemical Engineering, Jiangsu University, Zhenjiang, 212013, P.R. China.
Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, P.R. China.
Sci Rep. 2019 Nov 14;9(1):16863. doi: 10.1038/s41598-019-53212-3.
A new paradigm for photocatalysts based on two different hierarchically structured honeycomb and porous cylindrical Au-ZnO heterostructures was successfully developed via a straightforward and cost-effective hydrothermal method under different preparation conditions, which can be promising for industrial applications. The photocatalytic performance of all as-prepared samples under the illumination of sunlight was evaluated by the photocatalytic degradation of rhodamine B (RhB) and malachite green (MG) aqueous solutions. The results show that the photocatalytic degradation efficiency of RhB and MG was 55.3% and 40.7% for ZnO, 95.3% and 93.4% for the porous cylindrical Au-ZnO heterostructure, and 98.6% and 99.5% for the honeycomb Au-ZnO heterostructure, respectively. Compared with those from the ZnO, the results herein demonstrate an excellent reduction in the photoluminescence and improvement in the photocatalysis for the Au-ZnO hybrids with different morphologies. These results were attributed not only to the greatly improved sunlight utilization efficiency due to the surface plasmon resonance (SPR) absorption of Au nanoparticles in the visible region coupled with the UV light utilization by the ZnO nanostructures and multi-reflections of the incident light in the pore structures of their interior cavities but also to the high charge separation efficiency and low Schottky barrier generated by the combination of Au nanoparticles and ZnO micromaterials. Moreover, the honeycomb Au-ZnO heterostructure had a high Au content, surface area and surface oxygen vacancy (O), which enabled photocatalytic properties that were higher than those of the porous cylindrical Au-ZnO heterostructures. In addition, two different formation mechanisms for the morphology and possible photocatalytic mechanisms are proposed in this paper.
通过一种简单且经济高效的水热法，在不同制备条件下成功开发出一种基于两种不同层次结构的蜂窝状和多孔圆柱状金-氧化锌异质结构的光催化剂新范式，这对于工业应用可能具有广阔前景。通过罗丹明B（RhB）和孔雀石绿（MG）水溶液的光催化降解，评估了所有制备样品在太阳光照射下的光催化性能。结果表明，对于氧化锌，RhB和MG的光催化降解效率分别为55.3%和40.7%；对于多孔圆柱状金-氧化锌异质结构，分别为95.3%和93.4%；对于蜂窝状金-氧化锌异质结构，分别为98.6%和99.5%。与氧化锌的结果相比，本文结果表明不同形态的金-氧化锌杂化物的光致发光显著降低，光催化性能得到改善。这些结果不仅归因于金纳米颗粒在可见光区域的表面等离子体共振（SPR）吸收与氧化锌纳米结构对紫外光的利用以及入射光在其内部腔室孔结构中的多次反射，从而大大提高了太阳光利用效率，还归因于金纳米颗粒与氧化锌微材料结合产生的高电荷分离效率和低肖特基势垒。此外，蜂窝状金-氧化锌异质结构具有高金含量、表面积和表面氧空位（O），其光催化性能高于多孔圆柱状金-氧化锌异质结构。此外，本文还提出了两种不同的形态形成机制和可能的光催化机制。
