Fabrication of highly sensitive 4-Nitrophenol sensor and photocatalytic performance of multifunctional Ba0.5Sr0.5CoxHfxFe12-2xO19 Ferrite

In this approach, Ba0.5Sr0.5Fe12-2x(CoHf)xO19 ferrite samples have been successfully prepared using the conventional solid-state method, and single hexagonal crystal structure of the M-type hexaferrite phase have been formed according to the space group No. 194 (P63/mmc). The cation distribution in Ba0.5Sr0.5Fe12-2x(CoHf)xO19 has been defined. The bandgap energies of ferrite compositions are found to be 2.86, 2.83, 2.85, 2.89, 2.89, and 2.89 eV for different concentrations x = 0, 0.2, 0.4, 0.6, 0.8 and 1, respectively. The photocatalytic efficiencies were evaluated by degradation of an aqueous solution of Acridine Orange (AO) dye [0.03 mM] under visible light. Interestingly, the Ba0.5Sr0.5CoxHfxFe12-2xO19 at x = 0.4 exhibited the highest degradation rate of AO which was about 3.6 times larger than Ba0.5Sr0.5CoxHfxFe12-2xO19 at x = 0. The findings showed a slight decrease in the photocatalytic performance of compositions x = 0.0 after five cycles, indicating a stable photo-catalyst behavior. Additionally, a highly sensitive and selective electrochemical sensor on a glassy carbon electrode (GCE) for the detection of 4-nitrophenol (4-NP) has been fabricated with the similar Ba0.5Sr0.5CoxHfxFe12-2xO19 (x = 0.4) composition. The electrochemical linear responses of the 4-NP chemical sensor were studied over the concentration range (0.1 nM–0.01 mM), known as a linear dynamic range (LDR). The obtained slope from the calibration curve was applied in the calculation of the sensitivity (16.9114 μAμM−1cm−2), and detection limit (96.11 ± 4.81 pM) of the proposed 4-NP electrochemical sensor with Ba0.5Sr0.5CoxHfxFe12-2xO19 (x = 0.4) fabricated Nafion coated GCE. The Ba0.5Sr0.5CoxHfxFe12-2xO19 (x = 0.4)/Nafion/GCE sensor parameters were found to be reliable in performance of response time and repeatability in comparison to previous reports. Finally, the prepared Ba0.5Sr0.5CoxHfxFe12-2xO19 (x = 0.4) material is introduced in a new route by the photocatalytic and electrochemical approaches to remove colored and carcinogenic chemicals from the environmental and healthcare fields in a broad scale.