Mt-supported ZnO/TiO_2 nanocomposite for agricultural antibacterial agent involving enhanced antibacterial activity and increased wettability

摘要

Nano-scale antibacterial agents have attracted enthusiastic attention due to their size-dependent qualities, effective antibacterial activity, and unique physiochemical properties, which showed great application potential in plant protection and nutrition. In this work, Mt-supported ZnO/TiO2 nanocomposite was prepared through sol-gel assisted impregnation method, and its antibacterial activity against gram-positive bacteria (S. aureus) and the wettability on cucumber leaves was investigated. The results suggested that the pillaring of Mt by TiO2 increased BET specific surface area, improved Zn-dispersion, enhanced adsorption capacity, forming an exfoliation structure of TiO2 pillared Mt nanocomposite. Besides, Mt-supported ZnO/TiO2 nanocomposite showed an obvious increase of antibacterial activity and wetting property over pure ZnO and Mt-supported ZnO composite due to the doping of zinc oxide by carbon atoms and the increase of exposed active sites caused by the effective dispersion of ZnO. In addition, the optimal performance was achieved for 15.04% Zn element content with the diameter of the inhibition zone was 48.53 +/- 0.1 mm and the contact angle was 82.5 +/- 0.2 degrees attributed to the increased BET surface area (72.33 m2/g) and metal oxide interaction between TiO2 and Zn2+. The relatively low cost, green and environment friendly, high antibacterial activity, and wettability of Mt-supported ZnO/TiO2 nanocomposite offers new avenues for the antibacterial agent in the field of agriculture and crop protection.