A magnetic organic–inorganic composite: Synthesis and characterization of magnetic 5-aminosalicylic acid intercalated layered double hydroxides

A core–shell structured magnetic layered organic–inorganic material involving 5-aminosalicylic acid (5-ASA) intercalated Zn–Al layered double hydroxides (LDHs) and magnesium ferrite (MgFe2O4) is assembled by a coprecipitation method. The powder X-ray diffraction results show the coexistence of the clear but weak diffractions of MgFe2O4 and ordered relatively stronger reflections of 5-ASA intercalated LDHs. The TEM image of magnetic 5-ASA intercalated LDHs reveals that the LDHs layer covers the MgFe2O4 particles or their aggregates with particle size of 50–80 nm. The vibration sample magnetization (VSM) measurements exhibit the increase in saturation magnetization of magnetic 5-ASA intercalated LDHs samples with increasing amount of magnetic core. The XPS analyses account for a majority of Zn, Al and O atoms on the surface of magnetic particles. It is suggested that the magnetic core MgFe2O4 was coated with LDHs layer probably through Zn–O–Mg and Al–O–Mg linkages, and a core–shell structured model is tentatively proposed.