Structure and catalytic activity of magnetic composite photocatalyst SrFe12O19/SrTiO3

Abstract

SrFe12O19/SrTiO3 photocatalyst was synthesized with solgel method. The as-prepared composite catalyst was characterized by XRD, IR, SEM, BET, UV–vis and VSM. It was revealed that the specific surface area of SrFe12O19/SrTiO3 was larger than that of pure SrTiO3. The maximum absorption wavelength (λmax) of the composite was 550 nm, which located in visible light region. The saturation magnetizations (Ms), remanent magnetization (Mr) and coercivity (Hc) of the magnetic composite were 19.8emu/g, 10.5emu/g and 2500G, respectively. The activity of the catalysts was evaluated by photodegradation of methylene blue (MB), and the degradation ratio with 25% SrFe12O19/SrTiO3 was 98.6% at 2 h under the visible light illumination, while the degradation ratio with pure SrTiO3 was 30% at the same condition. The results indicated that 25% SrFe12O19/SrTiO3 held excellent photocatalytic activity as well as strong magnetization, which was beneficial to separate and recover completely. The recycling test confirmed that the magnetic composite catalyst was capable of using repeatedly, and the photocatalytic activity was above 80% after 5 cycles.