Mixed-Valent Mn-16-Containing Heteropolyanions: Tuning of Oxidation State and Associated Physicochemical Properties

Haider A; Ibrahim M; Bassil BS; Carey AM; Viet AN; Xing XL; Ayass WW; Minambres JF; Liu RJ; Zhang GJ; Keita B; Mereacre V; Powell AK; Balinski K; N'Diaye AT; Kupper K; Chen HY; Stimming U; Kortz U

Inorganic Chemistry, Vol.55, No.6, 2755-2764, 2016

DOI10.1021/acs.inorgchem.5b02503 Export Citation

Mixed-Valent Mn-16-Containing Heteropolyanions: Tuning of Oxidation State and Associated Physicochemical Properties

Haider A, Ibrahim M, Bassil BS, Carey AM, Viet AN, Xing XL, Ayass WW, Minambres JF, Liu RJ, Zhang GJ, Keita B, Mereacre V, Powell AK, Balinski K, N'Diaye AT, Kupper K, Chen HY, Stimming U, Kortz U

The two 16-manganese-containing, Keggin-based 36-tungsto-4-silicates [(Mn10Mn6O6)-Mn-III-O-II(OH)(6)(PO4)(4)(A-alpha-SiW9O34)(4)](28-) (1) and [(Mn4Mn12II)-Mn-III(OH)(12)(PO4)(4)(A-alpha-SiW9O34)(4)](28-) (2) have been prepared by reaction of the trilacunary Keggin precursor [A-alpha-SiW9O34](10-) with either Mn(OOCCH3)(3)center dot 2H(2)O (for 1) or MnCl2 center dot 4H2O (for 2), in aqueous phosphate solution at pH 9. Polyanions 1 and 2 comprise mixed-valent, cationic {(MnMnI6O6)-Mn-III-I-II(OH)(6)}(24+) and {(Mn10Mn6O6)-Mn-III-O-II(OH)(6)(PO4)(4) cores, respectively, encapsulated by four phosphate groups and four {SiW9} units in a tetrahedral fashion. Both polyanions were structurally and compositionally Characterized by single-crystal XRD, IR, therrnogravimetric analysis, and X-ray absorption,, spectroscopy. Furthermore, studies were performed probing, the magnetic, electrochemical, oxidation catalytic, and Li-ion battery performance of 1 and 2.