Green TiO2–ZnO nanocomposite stimulator for the growth of Solanum lycopersicum in aquaculture

The current study is focused on the green synthesis of TiO2–ZnO nanocomposite using Allium sativum leaf extract as a capping and reducing agent. It describes a unique application of green synthesized TiO2–ZnO nanocomposite in the soil-less water culture system that exhibits a significant influence on the germination and growth of Solanum lycopersicum plant. Here, Hogland nutrient solution was employed as a substitute for soil in the water culture system, which is used as the nutrient medium. Different concentrations of green synthesized TiO2–ZnO nanocomposites (10, 20, 30, 50, 100, 200, and 300 mg/L) compared to the control system were applied to investigate the growth of S. lycopersicum. The experimental investigation shows that a particular minimum concentration of the TiO2–ZnO nanocomposites (20 mg/L) in the Hogland nutrient solution shows the overall effective germination and growth for the S. lycopersicum. The synthesized sample was characterized with several spectroscopic and microscopic techniques: XRD, FESEM, EDS, XPS, TEM, BET, Raman, FTIR, and UV–Visible spectroscopy. The XRD pattern ensures the composition of anatase TiO2 and ZnO in the nanocomposite. The calculated average crystallite size 4.58 nm is comparable to the particle sizes (4–13 nm) as indicated by HR-TEM. FESEM displays the spherical shapes of nanostructures. EDS and XPS indicate the Ti, Zn, O as elemental compositions of the nanocomposite. The BET exhibits mesoporous nanostructures with a larger specific surface area of 133.824 m2/g. A larger surface area indicates greater adsorption of nutrients, can act as nutrient carriers, thus stimulates nutrient transportation and influences plants’ growth.