Synergizing hexagonal ferrite with transition metals in core-shell-shell nanostructures (SrFe@Dop@M) as dualistic probe for detoxification and electrochemical detection of pharmaceutical drugs

Abstract

A novel hexagonal ferrite-based core-shell-shell nanostructures (SrFe@Dop@M, M = Cr, Mn, Fe, Co, Ni, Cu and Zn) were designed for dual application of simultaneous electrochemical detection and photocatalytic degradation of pharmaceutical drugs. The phase analysis and topographical investigations of synthesized nanostructures were examined via PXRD, FE-SEM and HR-TEM techniques. XPS was employed to investigate the elemental composition and their corresponding electronic states. The electron transfer rate of synthesized nanostructures was estimated by EIS and CV studies. The comparative photocatalytic evaluation of SrFe, SrFe@Dop and SrFe@Dop@M was performed towards degradation of levofloxacin and sulfamethoxazole. SrFe@Dop@Mn was observed to portray best photocatalytic performance of around 3 times than that of bare SrFe and SrFe@Dop, attributable to its lowest energy band gap value and highest electron transfer rate. The SrFe@Dop@Mn glassy carbon electrode (GCE) was further employed as an electrochemical sensor towards detection of levofloxacin in waste water samples, providing impressive linear range from 55.2 nM to 772.8 nM and limit of detection as low as 0.037 nM. The real sample (tap water, lake water, river water and urine sample) analysis was evaluated to realize the practical applicability of modified sensor.