Structural, magnetic, dielectric, and antimicrobial investigations of enhanced Zn-doped Ni nano chromites

Low temperature citrate gel route is employed for the synthesis of nano structured zinc substituted nickel chromites by using spinel formula of Ni 1-x Zn x Cr 2 O 4 where x is taken as 0.0 to 1.0 by 0.2 variation. The synthesized nano chromites structural parameters have been characterized by applying instrumental techniques like XRD, the powder XRD spectrum confirmed the single-phase FCC structure with the Fd3M space group, and the material's average crystalline size was found to be in the 9–20 nm range. Shape and size of the prepared samples have been investigated by using FESEM analysis, EDS spectrum gives the elemental analysis and quantitative data of as prepared chromites according to the stoichiometric ratios. Anti-microbial (anti-bacterial and anti- fungal) activity was studied upon bacterial pathogens of staphylococcus, bacillus, E. coli and klebsiella, fungal pathogens of candida, aspergillus among the three samples labeled as Ni-1, Ni-3 and Ni-6, ZnCr 2 O 4 (Ni-6) shown more activity towards both bacterial and fungal pathogens. Dielectric parameters like dielectric constant, AC conductance and dielectric loss tangent (tan δ) of the prepared chromites with concentrations of x = 0.0, 0.4, 0.8 and 1.0 were calculated by using LCR meter at high temperatures with the applied frequency of 10 Hz-1 MHz and the magnetic properties of Ni Zn chromites were analyzed at room temperature using a vibrating sample magnetometer (VSM). The results show a decrease in magnetic coercivity with increasing Zn content. The results strongly suggest that Zn-doped nickel chromites have significant medical, electrical and magnetic applications. Zone of inhibition of Ni Zn chromites against bacterial agents. Room temperature magnetic hysteresis loops of Ni 1-x Zn x Cr 2 O 4 (x = 0.0, 0.4, 0.8 & 1.0).