Solar-light-driven photocatalytic performance of Cr and Co doped Sr1-xCoxFe12-yCryO19 and effect of doping on optical, structural and dielectric properties

Abstract

A series of Co2+ and Cr3+ doped strontium hexaferrite (Sr1-xCoxFe12-yCryO19) nanoparticles were synthesized via micro-emulsion technique. Effect of Co and Cr ions doping was estimated using structural, dielectric, photocatalytic and optical properties of Sr1-xCoxFe12-yCryO19. The Sr1-xCoxFe12-yCryO19 were characterized employing X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR), (Scanning electron microscopy) SEM and UV–Vis spectroscopy. The XRD analysis confirmed formation of hexagonal M-type ferrites with average crystallite size of 38 nm. Dielectric properties analysis revealed that the of Sr1-xCoxFe12-yCryO19 has high dielectric constant, low dielectric and tangent loss versus SrFe12O19. The band gap energy decreased with the Co2+ and Cr3+ contents due to incorporation of sub band gaps and reduction of particle size. The photocatalytic activity (PCA) of Sr1-xCoxFe12-yCryO19 was evaluated by degrading the Rhodamine B (RhB) dye under solar light irradiation. The Sr1-xCoxFe12-yCryO19 degraded up to 87.6% of dye in 45 min of solar light irradiation with rate constant of 0.03834 min−1. Results revealed that Co2+ and Cr3+ doping tuned the optical properties and Sr1-xCoxFe12-yCryO19 has potential to harvest the solar light for photocatalytic applications. The high electrical conductivity and tuned band gap make such materials as feasible to utilize them efficiently in photovoltaic cells, SOFCs and as an encouraging photocatalyst for water remediation.