Solution combustion synthesis of CaFe2O4 nanocrystal as a magnetically separable photocatalyst

• CaFe2O4 nanocrystals were prepared by a solution combustion synthesis method.
• CaFe2O4 showed high photo-activity in the degradation of methylene blue.
• The CaFe2O4 nanocrystals can be easily separated by the application of a magnet.

Magnetic CaFe2O4 photocatalyst was successfully synthesized via a solution combustion synthesis (SCS) method, using glycine as the fuel. The as-prepared CaFe2O4 nanoparticles had an average size of 100 nm and broad photo-absorption range. Its band gap calculated from the adsorption edge was fixed at 1.82 eV, which suggested that it could be excited by visible-light. The photo-degradation of methylene blue (MB) under visible light, demonstrated that the CaFe2O4 nanocrystals exhibited high photocatalytic activity. The enhanced photocatalytic activity could be attributed to the small particle size of the CaFe2O4 nanocrystals. Moreover, the product could be easily recycled from the solution by applying an external magnetic field.