A Simple Preparation Process of Pure Mn3-xCoxO4 (x = 1, 1.5 and 2) Desert Rose-Like Nanoparticles and Their Optical Properties

Abstract

Monodisperse CoMn₂O₄, Co_1.5Mn_1.5O₄ and Co₂MnO₄ nanoparticles were prepared by a rapid and low cost method. The organic and complex dispersing agent free synthesis of stable colloidal suspensions containing pure nanoparticles of spinel oxides was optimized at low temperature (T<100 °C). The key point of the synthesis is the fast introduction of the precursor solution into a much larger volume of alkaline solution buffered with LiOH. XRD, SEM-FEG and HRTEM performed on desert rose-like nanoparticles showed that nanoparticles are crystallized and of uniform shape/size distributions. Thermogravimetric analyses give an insight into the sample composition of nanopowders in relation with semiconductor ceramic counterparts. The UV-Vis absorption spectra of these pure spinel oxide nanoparticles in solution are discussed.