Abstract

A novel visible light active and magnetically separable nanophotocatalyst, Ni_0.5Zn_0.5Fe₂O₄/Zn_0.95Ni_0.05O (denoted as NZF@Z), with varying amount of Ni_0.5Zn_0.5Fe₂O₄, has been synthesized by egg albumen assisted sol gel technique. The structural, optical, magnetic, and photocatalytic properties have been studied by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), fourier transform infrared spectroscopy (FTIR), UV–visible (UV–Vis) spectroscopy, and vibrating sample magnetometry (VSM) techniques. Powder XRD, TEM, FTIR and energy dispersive spectroscopic (EDS) analyses confirm coexistence of Ni_0.5Zn_0.5Fe₂O₄ and Zn_0.95Ni_0.05O phases in the catalyst. Crystallite sizes of Ni_0.5Zn_0.5Fe₂O₄ and Zn_0.95Ni_0.05O in pure phases and nanocomposites, estimated from Debye–Scherrer equation, are found to be around 15–25 nm. The estimated particle sizes from TEM and FESEM data are ∼(22 ± 6) nm. The calculated energy band gaps, obtained by Tauc relation from UV–Vis absorption spectra, of Zn_0.95Ni_0.05O, 15%NZF@Z, 40%NZF@Z and 60%NZF@Z are 2.95, 2.72, 2.64, and 2.54 eV respectively. Magnetic measurements (field (H) dependent magnetization (M)) show all samples to be super-paramagnetic in nature and saturation magnetizations (M_s) decrease with decreasing ferrite content in the nanocomposites. These novel nanocomposites show excellent photocatalytic activities on Rhodamin Dye.