Structure and properties of ZnO/ZnMn2O4 composite obtained by thermal decomposition of terephthalate precursor

Abstract

A biphasic [Mn(dipya)(H2O)4](tpht)/{[Zn(dipya)(tpht)]·H2O}n complex material, I, (dipya = 2,2’-dipyridylamine, tpht2– = dianion of terephthalatic acid) was synthesized by ligand exchange reaction and characterized by XRPD and FTIR spectroscopy. A ZnO/ZnMn2O4 composite, II, has been prepared via thermal decomposition of precursor I in an air atmosphere at 450 °C. XRPD, FTIR and FESEM analyses of II revealed the simultaneous presence of spherical nanoparticles of wurtzite ZnO and elongated nanoparticles of spinel ZnMn2O4. The specific surface area of II was determined by the BET method, whereas the volume and average size of the mesopores were calculated in accordance with the BJH method. The measurements of the mean size, polydispersity index and zeta potential showed colloidal instability of II. Two band gap values of 2.4 and 3.3 eV were determined using UV–Vis diffuse reflectance spectroscopy, while the measurements of photoluminescence revealed that II is active in the blue region of the visible spectrum. Testing of composite II as a pigmentary material showed that it can be used for the colouring of a ceramic glaze.