Compounds and solid solutions of cobalt, copper phosphates

Journal Article · Sun Nov 01 04:00:00 EST 1998 · Journal of the American Ceramic Society

DOI:https://doi.org/10.1111/j.1151-2916.1998.tb02699.x· OSTI ID:289491

Bamberger, C E; Specht, E D; Anovitz, L M ^[1]

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1. Oak Ridge National Lab., TN (United States)

Cobalt phosphates have been synthesized and their thermal behavior examined. The formation of compounds and solid solutions among cobalt and copper phosphates is studied by X-ray diffraction. Unlimited solubility exists between the pyrophosphates Co{sub 2}P{sub 2}O{sub 7} and Cu{sub 2}P{sub 2}O{sub 7}, the orthophosphates Co{sub 3}(PO{sub 4}){sub 2} and Cu{sub 3}(PO{sub 4}){sub 2}, and Co{sub 3}(PO{sub 4}){sub 2} and Cu{sub 2}P{sub 2}O{sub 7}. X-ray diffraction indicates that the structures of cobalt and copper pyrophosphate solid solutions vary gradually from one end member to the other. The structures of orthophosphate solid solutions vary in a more complex manner: the change is gradual from Co{sub 3}(PO{sub 4}){sub 2} to Co{sub 2}Cu(PO{sub 4}){sub 2}. At Co{sub 1.5}Cu{sub 1.5}(PO{sub 4}){sub 2}, a new structure (L) occurs. At 950 C, CoCu{sub 2}(PO{sub 4}){sub 2} also exhibits this structure, which is similar to that of graftonite, Fe{sub 3}(PO{sub 4}){sub 2}. CoCu{sub 2}(PO{sub 4}){sub 2} is dimorphic, changing reversibly at 1000 C to a triclinic structure (H) related to that of Cu{sub 3}(PO{sub 4}){sub 2}. From CoCu{sub 2}(PO{sub 4}){sub 2} (H) to Cu{sub 3}(PO{sub 4}){sub 2}, the structure appears to vary gradually. A new phosphate, Cu{sup +}Cu{sup 2+}Co{sub 3}(PO{sub 4}){sub 3}, has also been synthesized.

• Sponsoring Organization: USDOE
• OSTI ID: 289491
• Journal Information: Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 11 Vol. 81; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COBALT PHOSPHATES
COPPER PHOSPHATES
MOLECULAR STRUCTURE
SOLID SOLUTIONS
STOICHIOMETRY
SYNTHESIS
X-RAY DIFFRACTION