Well-organized assembly of ZnO hollow cages and their derived Ag/ZnO composites with enhanced photocatalytic property

• Published in: Materials characterization 2020-02, Vol.160, p.110125, Article 110125
• Main Authors: Cao, HuaMin, Liu, Zhao, Liu, Tingzhi, Duo, Shuwang, Huang, Lin, Yi, Siqin, Cai, Linlin
• Format: Article
• Language: English
• Subjects: Ag/ZnO composite; Formation mechanism; Photocatalytic activity; Well-organized ZnO hollow cage
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2020.110125

Unique and controllable well-organized ZnO hollow cages were formed for the first time by smart assembly using novel combination of L-TA and EA, which can produce a strong synergistic effect in hydrothermal process. Meanwhile, the conformation of L-TA and D-TA shows that these ZnO cages have special spatial assembly order. The photocatalytic activity of Ag/ZnO is remarkably larger than that of pristine ZnO (S2) under UV or simulated sunlight irradiation. The MB rate constant k values of Ag/ZnO composites are larger than those of P25 under UV light illumination. Under simulated sunlight irradiation, S2-10% Ag/ZnO degrades 80% of RhB in 135 min. The PL, photocurrent and EIS results indicate enhanced photocatalytic performance due to the interfacial formation between Ag and ZnO, which facilitates the separation and transfer of photoinduced carriers and enhances the photocatalytic activity of Ag/ZnO composites. This work provided a new way to design and construct well-organized ZnO hollow cages and their derived Ag/ZnO photocatalysts. 1.Unique well-organized ZnO hollow cages can be designed, constructed and formed with synergistic effect of novel combination of L−TA and EA for the first time. The assembly of WO-ZnO-HCs exhibits regular arrangement along the edge of hexagonal bottom (the center is empty), and has special spatial stacking order. Then Ag/WO-ZnO-HC composites were further constructed for the enhancement for photocatalytic activity.2.PL, photocurrent and EIS results show that the formation of heterostructured Ag/WO-ZnO-HCs obviously facilitates the separation and transfer of photoinduced electron-hole pairs, which leads to enhanced photocatalytic performance than that of pristine ZnO under UV and simulated solar light irradiation simultaneously.3.The dyes of CR, MB, MO, and RhB were photodegraded quickly under the UV light illumination, especially MB rate constant K of Ag/WO-ZnO-HCs is larger than that of commercial P25.4.WO-ZnO-HCs assembly mechanism were proposed in detailed. [Display omitted] •Unique well-organized ZnO hollow cages were stably formed via novel combination of L-TA and EA.•Formation of Ag/ZnO composites obviously facilitate the separation and transfer of the photoinduced electron-hole pairs.•Photocatalytic activity of Ag/ZnO composites is remarkably larger than that of pristine ZnO.•MB photodegradation rate constant of Ag/ZnO composites is larger than that of commercial P25 under illumination of UV light.•Assembly and photocatalyt