Characterizations of TiO2@Mn-Zn ferrite powders for magnetic photocatalyst prepared from used alkaline batteries and waste steel pickling liquor

Abstract We successfully prepared the TiO 2 @Mn-Zn ferrite composite powder for magnetic photocatalyst. The core Mn-Zn ferrite powder was synthesized by using steel pickling liquor and used alkaline batteries as the starting materials. The shell TiO 2 nanocrystal was prepared by sol–gel hydrolysis precipitation of titanium isopropoxide (Ti(OC 3 H 7 ) 4 ) on the Mn-Zn ferrite powder. The thickness of the titania shell was found to be approximately 2 nm. The core of Mn-Zn ferrite is of spherical or elliptical shape and the particle size of the core is in the range of 20–40 nm. The magnetic Mn-Zn ferrite nanopowder is uniformly encapsulated in a titania layer forming the core–shell structure of TiO 2 @Mn-Zn ferrite powder. The magnetic photocatalyst can be successfully used to treat dye waste waters.