Synthesis, structure, thermal, magnetic, dielectric properties of Ce3+ doped M-type SrFe12O19 and electrochemical determination of L-cysteine

Abstract

• Nanostructured Sr (1-x) Ce x Fe 12 O 19 nanoferrites were prepared by auto combustion method with dual fuel (Urea and glycine). • The dielectric properties of all the samples have been measured using LCR meter at room temperature and electrochemical studies was using by cyclic voltammetry at RT. • The XRD patterns and IR spectra confirmed the formation of hexagonal structure. • The dielectric parameters decreases while AC conductivity increases with frequency. At a particular frequency, the dielectric constant, dielectric loss real part and imaginary part of impedance increases, attain maximum, then begins to decrease with increase in composition. • The SrHF’s/GCE electrode showed impressive results including increased sensitivity, limit of detection, higher concentration range, stability, and reproducibility properties. Cerium substituted SrFe 12 O 19 with the nano composition of Sr (1-x) Ce x Fe 12 O 19 ( x = 0.00, 0.01, 0.05 and 0.09) have been prepared using auto-combustion technique with dual fuel. The PXRD images confirmed a single-phase hexagonal crystalline structure similar to a magnetoplumbhite for all samples. Fourier transform infra-red spectroscopy (FT-IR), field emission-scanning electron spectroscopy (FE-SEM), elemental mapping (EDS) were used to examine for the structure and morphology of the samples. The temperature dependent hexagonal phase formation and percentage weight loss was studied by thermogravimetric and differential thermal analysis (TG-DTA). Vibrating sample magnetometer (VSM) analysis confirmed that M-SrHF’s are hard magnetic in nature and super paramagnetic, these are measured at room temperature. It was found that, with the increase of the dopant Ce 3+ in strontium ferrites, the values of saturation magnetization (M S ), remanence magnetization (Mr), coercivity (H C ) and magnetic parameters of strontium ferrites decrease. The electrochemical behavior of the SrHF’s electrode and the electro-oxidation of L-cysteine was investigated using of cyclic voltammetry (CV). The best voltammetric response has been observed for a SrHF’s electrode in buffer solution at pH of 7.0 with an acquisition and scan rate of 50 mV s − 1 . The dielectric properties are measured in LCR meter and described based on the Maxwell–Wagner’s two layer model. The electron hopping between Sr 2+ and Sr 3+ , as well as Fe 3+ and Fe 2+ ions on B-sites, drives the conduction mechanism in these ferrites, these nano hexaferrites which shows its suitability in various technological applications.