A rapid co-precipitation and non-isothermal decomposition kinetics of new binary Mn 0.5Co 0.5(H 2PO 4) 2·2H 2O

Abstract

New binary metal dihydrogenphosphate dihydrate Mn 05Co 0.5(H 2PO 4) 2·2H 2O was synthesized by a rapid and simple co-precipitation method using phosphoric acid, manganese and cobalt carbonate at ambient temperature. The thermal stability of Mn 05Co 0.5(H 2PO 4) 2·2H 2O was studied by means of the non-isothermal kinetics (Kissinger method). The synthesized Mn 05Co 0.5(H 2PO 4) 2·2H 2O showed the complex thermal transformations and its final decomposition product was a new binary metal cyclotetraphosphate, MnCoP 4O 12. The XRD, SEM, UV–vis–near IR and FTIR results of the synthesized Mn 05Co 0.5(H 2PO 4) 2·2H 2O and the decomposed MnCoP 4O 12 appear to be very similar to that of M(H 2PO 4) 2·2H 2O and M 2P 4O 12 (M = Mn and Co), which indicate the monoclinic phase with space group P2 1/ n and C2/ c, respectively. The dominant feature of the synthesized Mn 05Co 0.5(H 2PO 4) 2·2H 2O and the decomposed MnCoP 4O 12 are compared with M(H 2PO 4) 2·2H 2O and M 2P 4O 12 (M = Co and Mn), respectively.