Gd-doped Ni–Zn ferrite nanoparticles: an approach to enhance photocatalytic efficiency through property tuning

Abstract

This work thoroughly investigated the adaptability of Gd-incorporated spinel Ni–Zn ferrite nanoparticles in hyperthermia and photocatalytic applications. The chemical co-precipitation method was utilized to fabricate these ferrite nanoparticles containing different weight percentages of Gd dopants, and tuned physical properties, including microstructural, optical, and magnetic were examined. The formation of spinel cubic crystal structure and phase-purity of prepared samples was confirmed by analyzing the x-ray diffractograms. Both the developed microstrain due to doping and mean crystallite sizes were estimated using the Williamson-Hall (W–H) graph. With the aid of HRTEM images, the morphology, average size of nanoparticles and regularity in shape were studied carefully. Mean particle diameters of entire ferrite samples were observed to reduce with the increase of Gd ions in the host structure. A blue shift in the optical indirect band gaps with the increase of Gd content was noticed for synthesized ferrite samples. All the Raman active modes of spinel structure were found in deconvoluted Raman spectra. Because of the paramagnetic behavior of Gd ions, there was a dilution of magnetic properties observed at room temperature. A careful investigation revealed that the doped ferrite samples were suitable for hyperthermia application as the generated heat was suitable to burst cancer cells in a biological medium. Because of the increase in specific surface area and magnitude of negative zeta potential for doped ferrite nanoparticles, these samples showed excellent efficiency in degrading toxic cationic rhodamine B (RhB) dye. The highest Gd-doped ferrite containing the smallest nanoparticles was capable enough to degrade 94.6% RhB dye in 2.5 h. With increasing Gd content in nanosized spinel Ni–Zn ferrites, the efficiency of dye degradation was found to increase significantly. Therefore, Gd-substituted Ni–Zn ferrite nanoparticles are efficient nanomaterials to be utilized in both photocatalytic and hyperthermia applications.

Graphical abstract