Phytofabrication of TiO 2 NPs using Oils of Coriandrum Sativum (Apiaceae) Seeds and their Eco-Friendly Application

Abstract

Titanium dioxide nanoparticles were synthesized following the green and chemical method. The green method utilized coriander seed oil extract to produce the titanium dioxide nanoparticles through the respective role of reducing and stabilizing agent. The chemical method employed sodium hydroxide and followed high-temperature heat treatment synthesis. The extracts utilized were produced under hot extraction condition (~ 100 °C, pH 8.0) and via Soxhlet extraction as a solid-liquid extraction technique using 70% ethanol. Both extracts were dried in an oven at 50 °C for 3 h. The synthesized titanium dioxide nanoparticles were characterized by UV-visible spectroscopy, XRD and FTIR. The characterization results show that both synthesized nanoparticles had comparable optical and structural properties. Scanning Electron Microscopy (SEM) showed that the average particle size was ~32 nm from the extract utilizing the green synthesized methods and ~50 nm for the chemical synthesis method. The small particle size from green synthesized nanoparticles can be attributed to phytochemicals in coriander oil acting to limit agglomeration and regulate growth, while the chemical synthesis had high temperature that uncontrolled nucleation allowed for agglomeration. Photocatalytic degradation of methylene blue showed the green nature titanium dioxide nanoparticles performed better methylene blue degradation than the chemically synthesized. The improved degradation can be attributed to the greater surface area-to-volume ratio and greater number of active sites producing radical species. The results confirmed that green synthesized titanium dioxide maintains the crystalline phase, improves the morphological properties, offers a sustainable solution for synthesizing titanium dioxide, and provides an effective, green nanocatalyst for environmental remediation.