Metal ion-mediated structure and properties of α-Fe2O3 nanoparticles

To assess the relationship between metal ion-mediated microstructures and the macro-performance, Cu- and Zn-doped alpha-Fe2O3 nanoparticles were prepared via a solvothermal method. The morphologies of the as-synthesized nanoparticles were investigated by scanning electron microscopy and transmission electron microscopy. The results revealed that the sizes and morphologies could be regulated by doping with divalent cations. The structures of the as-synthesized nanoparticles were characterized by X-ray diffraction and Raman spectroscopy, indicating that Cu2+ and Zn2+ ions had diffused into the lattice of alpha-Fe2O3 matrix. The magnetization behaviors of these nanoparticles were measured to analyze the effect of doping on alpha-Fe2O3. Furthermore, the catalytic activities of Cu- and Zn-doped alpha-Fe2O3 nanoparticles demonstrated that the high-temperature decomposition temperature of ammonium perchlorate could be lowered by 115 degrees C and 107 degrees C, respectively, compared to that of ammonium perchlorate without catalyst. The enhanced catalytic activity could be attributed to the defect structure induced by doping with divalent cations.