Synthesis of MnAl2O4 nanocrystallites by Pechini and sequential homogenous precipitation methods: characterization, product comparison, photocatalytic effect, and Taguchi optimization

Nanocrystalline manganese aluminate (MnAl₂O₄) has been synthesized by Pechini and sequential homogenous precipitation methods and the results have been compared. The Taguchi L₄ statistical design was utilized to optimize the production of MnAl₂O₄ nanoparticles by Pechini method. The MnAl₂O₄ nanocrystallites obtained by Pechini and sequential homogenous precipitation methods had the average particle size of 26.5 and 49.5 nm, respectively. The products were characterized with X-ray diffraction, laser light scattering, thermogravimetry analysis, Fourier transform infrared, UV–visible, energy dispersive X-ray, scanning electron microscope and inductively coupled plasma analyses. The photocatalytic activities of MnAl₂O₄ nanoparticles synthesized by two methods were investigated using aqueous solution of methylene blue under irradiation of visible light.