Radiolytic synthesis of BaSO4 microspheres

The solid BaSO4 microspheres, mainly consisting of quasi-spherical nanoparticles, were successfully synthesized by precipitating Ba2+ ions with SO42− ions, which were generated from the reduction of K2S2O8 in the presence of EDTA under N2 atmosphere by γ-irradiation. It was found that the controlled release of SO42− played an important role in the formation of the microspheres.