Solar light-based photocatalytic removal of CV and RhB dyes using Bi and Al doped SrFe12O19 NPs and antibacterial properties

The SrBixAlxFe12-2xO19 (x = 0.0–1.0) nano-hexaferrites were prepared via facile micro-emulsion method and ferroelectric, dielectric, magnetic, photocatalytic and antibacterial properties were investigated based on doping contacts. The XRD analysis confirmed the hexagonal single-phase material with P63/mmc space group. P-E loops indicated the higher polarization and coercivity values for doped materials. VSM results showed that maximum and remnant magnetizations were quite high for undoped material while coercivity was low than doped hexaferrite. Optical band gap was reduced to 1.63 eV from 2 eV (pristine) for highly doped composition. PL intensity showed a sharp decline with doping, which indicated the better inhibition of charge carriers on doping. The photo-catalytic activity of pristine and the doped SrBixAlxFe12-2xO19 was investigated using Crystal Violet and Rhodamine B dyes under solar irradiation. SrAlxBixFe12-2xO19 (x = 1.0) exhibited improved catalytic efficiency and up to 83 and 86 (%) removal of CV and RhB dyes with rate constant of 0.047 and 0.048 (min−1), respectively. Highly doped ferrite also showed enhanced bactericidal action against S. aureus and E. coli strains. Superior mineralization of textile dyes and good antimicrobial activity of Bi and Al doped strontium nano-hexaferrites make such material as crucial candidate for solar light responsive photocatalytic and antimicrobial applications.