Mechanochemical effects on formation and properties of zinc - manganese pyrophosphates

Abstract

The mixtures of ammonium dihydrogenphosphate, zinc carbonate, and manganese carbonate with the molar ratios of P/(Zn+Mn) = 1/1 and Mn/Zn = 0/100, 0.5/99.5, 1/99, 2/98, 20/80 were ground with planetary-mill. The thermal behavior of milled samples was investigated with differential thermal analyses, X-ray diffraction, and Fourier transform infrared spectroscopy. In addition, thermal products were estimated from scanning electron micrograph, particle size distribution, specific surface area, and fluorescence spectra. By mechanochemical treatment, the substitution reaction to NH₄ZnPO₄ took place without heating. Because the mechanical treatment before heating improved the sintering of phosphate, the specific surface area became small. The fluorescent peak appeared in the spectra of materials at lower temperature by milling.