Green Synthesis of TiO₂ Using Impatiens rothii Hook.f. Leaf Extract for Efficient Removal of Methylene Blue Dye

Abstract

In this work, TiO2 nanoparticles (NPs) were effectively synthesized by a green method using the Impatiens rothii Hook.f. leaf (IL) extract as a capping and reducing agent. The as-synthesized TiO2 NPs were characterized by different characterization methods such as the Brunauer–Emmett–Teller (BET) analysis, high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), diffused reflectance spectroscopy (DRS), and X-ray diffraction (XRD) and Raman spectroscopy. The specific surface area from BET analysis was found to be 65 m2/g. The average crystallite size from XRD analysis and average particle size from SEM analysis were found to be ∼11 and ∼25 nm, respectively. The Raman spectroscopy and XRD results showed that the biosynthesized (IL–TiO2) nanoparticles were purely anatase phase. XPS analysis illustrated the formation of Titania with an oxidation state of +4. The DRS study showcased that a blue-shifted intense absorption peak of IL–TiO2 (3.39 eV) compared to the bulk material reported in the literature (3.2 eV). HRTEM micrograph showed the presence of grain boundary with d spacings of 0.352, 0.245, and 0.190, which correspond to the lattice planes of (101), (004), and (200), respectively. From the EDX analysis, the weight percents of titanium and oxygen were found to be 54.33 and 45.67%, respectively. The photoinduced degradation of methylene blue (MB) dye was investigated in the presence of biosynthesized IL-TiO2 NPs photocatalyst. The effect of parameters like catalyst dosage (30 mg/L), initial concentration of MB (15 ppm), pH (10.5), and contact time (100 min) on the removal efficiency was optimized. The maximum photodegradation efficiency under the optimized conditions was found to be 98%.

Characterization of titanium dioxide nanomaterials synthesized from leaf extract of Pogostemon cablin Benth and their potential antifungal activity

“…The average particle size calculated from the TEM analysis is more than the average crystalline size obtained from XRD data using Scherrer equation, possibly because of aggregation and agglomeration effect. After getting attached, two or more than two particles give this effect [22]. The Selected Area Electron Diffraction (SAED) pattern of both the TiO 2 chemically synthesized and green synthesized confirmed that the nanoparticles vibration [19,45].…”

“…Many studies have reported that due to the many phytochemicals (phenolics, terpenoids, etc), plant extract can act as a reducing and stabilizing agent by converting metal salt into nano form [16,17]. There are many studies reported synthesis of metallic nanoparticles using plants extract of jasmine flower [18], papaya [19], Piper nigrum, Coriandrum sativum, Syzygium aromaticum [20], rosemary, ginger [21], Impatiens rothii [22], Terenna asiatica [23], Garcinia mangostana [24], Iranian propolis [25], mango [26].…”