A simple method for preparation of superparamagnetic porous silica

A simple method was described for the preparation of porous silica with superparamagnetic properties. The mesopores of as-prepared composite silica were dispersed with magnetic nanoparticles. The prepared samples were characterized by XRD, TEM, BET and vibrating sample magnetometry (VSM). Results showed that such magnetic composite material exhibited large surface areas (377.4 m2/g), high pore volumes (0.65 cm3/g) and large pore size (7.05 nm). Furthermore, it exhibited another advantage (recyclability) because it can be magnetically separated by an external magnetic field. In the preparation, it was easily to synthesize porous silica with tunable magnetic properties by changing the ratio of the different precursors. Therefore, the composite would be a good choice for catalytic supports.