Study of Phase Relationships within the MgO‐CuO‐Cu2O‐P2O5 System

Abstract

The formation of the known compound Cu + Cu 2+ Mg 3 (PO 4 ) 3 by alternate reactions and its thermal stability were studied. The formation of solid solutions of the types Mg 2−x Cu x P 2 O 7 and Mg 3−x Cu x (PO 4 ) 2 was reexamined, mainly to aid in the identification of the products of decomposition of Cu + Cu 2+ Mg 3 (PO 4 ) 3 . X-ray diffractometry patterns of Mg 2−x Cu x P 2 O 7 varied gradually in the range 0 ≤ x ≤ 2, which indicates complete miscibility.

Orthophosphates and Diphosphates Containing Zinc and Copper and Zinc and Cobalt

“…The ␦and ␥-phases seem to be the ones with the most-limited ranges of stability. 3 The existence of Cu + Cu 2+ PO 4 and Cu + Cu 2+ M 3 (PO 4 ) 3 , in which M ‫ס‬ Mg or Co, led us to attempt to synthesize Cu + ZnPO 4 and Cu + Cu 2+ Zn 3 (PO 4 ) 3 using reactions that were similar to those that were used previously with the other metal ions: 6,8,9 e.g., Zn 2 P 2 O 7 + Cu 2 O, 3Zn 2 P 2 O 7 + Cu 2 O + 2CuO, 2Zn 3 (PO 4 ) 2 + Cu 3 (PO 4 ) 2 + Cu 0 , and 2Zn 3 (PO 4 ) 2 + Cu 2 P 2 O 7 + Cu 2 O at 880°-1025°C. None of the reactions were successful in producing the desired compounds; instead, mixtures were obtained in which known Cu 2+ -and zinc-containing phases, together with Cu 0 and Cu 2 O, were predominant.…”