Tailoring CuO-Fe₂O₃ nanocomposites via mechanochemical synthesis and calcination for efficient photocatalytic fluorescein removal

Abstract

The Copper Oxide-Iron Oxide Nanocomposites (CuO-Fe2O3 NCs) were fabricated via simple grinding process using mortar and pestle and were then subjected for calcination at 300, 600, and 900 °C for 3 h. Various physicochemical techniques including X-ray diffraction (XRD), energy dispersive X-rays (EDX), Fourier Transform Infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS) and N2 adsorption were employed to analyze the physicochemical properties of CuO-Fe2O3 NCs. It has been observed that the calcination temperature greatly affected the sample crystallinity, morphological features, band gap energy, chemical composition and surface area of the CuO-Fe2O3 NCs. The particles size and crystallinity of the samples increases with increasing calcination temperature whereas as the surface area has an inverse relation with calcination temperature. To degrade fluorescein, the fabricated NCs were utilized as photocatalyst under solar light irradiation. The temperature induced structural and optical variations had strong impact on the photocatalytic behavior of the samples and the activity was seen to decrease with increasing calcination temperature. The highest activity (88.95 %) was recorded for uncalcined sample. Moreover, the effect of initial dye concentration, catalyst dose, and pH along with recycling stability of the catalysts was studied.

Keywords

• Mechanochemical
• Nanocomposite
• Photocatalysis
• Sustainable