3D ZnO sunstar rose nanoflowers morphology with surfactant-assisted reflux exhibit excellent optical properties and photocatalytic activity against hazardous organic dyes

Abstract

Sunstar rose ZnO nanoflowers morphology was synthesized using the surfactant-assisted reflux technique. The synthesized 3D ZnO nanoflowers were subjected to various characterization techniques (X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV–Vis diffuse reflectance spectroscopy (UV-DRS), Photoluminescence (PL) spectroscopy, Raman spectra, thermogravimetry analysis (TGA), differential thermal analysis (DTA), X-ray photoelectron spectrometer (XPS), N2 adsorption-desorption isotherms (BET), field emission scanning electron microscopy (FESEM), energy dispersive X-rays analysis (EDAX) and high resolution transmission electron microscopy (HRTEM)). The sunstar rose morphology was achieved under reflux conditions; the heating throughout the material uniformly allowed the nanoflowers to grow along the c-axis due to the temperature, and surfactant also plays a significant role in the shape of the flowers, as confirmed by FESEM and HRTEM analysis. Further, the synthesized 3D ZnO nanoflowers were utilized the photocatalytic activity was investigated for the degradation of hazardous organic dyes like cationic (Methylene blue (MB)) and anionic (Indigo Carmine (IC)) under sunlight. Overall, it was observed that the degradation of MB and IC was found to be 99.5 (50 min) and 98% (60 min), respectively. ZnO nanoflowers are an efficient photocatalyst for MB compared to IC, as MB degrades faster than IC, which takes less time for degradation.Moreover, shown through photocatalytic processes that synthesized ZnO nanoflowers were highly recyclable, suggesting their potential application in environmental remediation. After the fourth cycle, the effective degradation of MB and IC was 78 and 70%, respectively. The radical quenching test shows that ZnO exhibits charge migration, which may account for its high photoactivity.