9‑Cobalt(II)-Containing 27-Tungsto-3-germanate(IV): Synthesis, Structure, Computational Modeling, and Heterogeneous Water Oxidation Catalysis

• Published in: Inorganic chemistry 2019-09, Vol.58 (17), p.11308-11316
• Main Authors: Haider, Ali, Bassil, Bassem S, Soriano-López, Joaquín, Qasim, Hafiz M, Sáenz de Pipaón, Cristina, Ibrahim, Masooma, Dutta, Daipayan, Koo, Yong-Sun, Carbó, Jorge J, Poblet, Josep M, Galán-Mascarós, José Ramón, Kortz, Ulrich
• Format: Article
• Language: English
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/acs.inorgchem.9b01495

The 9-cobalt­(II)-containing trimeric, cyclic polyanion [Co9(OH)3(H2O)6(PO4)2(B-α-GeW9O34)3]21– (1) was synthesized in an aqueous phosphate solution at pH 8 and isolated as a hydrated mixed sodium–cesium salt. Polyanion 1 was structurally and compositionally characterized in the solid state by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, as well as thermogravimetric and elemental analyses. The magnetic and electrochemical properties of 1 were also studied and compared with those of its phosphorus analogue, [Co9(OH)3(H2O)6(HPO4)2(B-α-PW9O34)3]16– (Co 9 -P). The electrochemical water oxidation activity of the cesium salt of 1 under heterogeneous conditions was also studied and shown to be superior to that of Co 9 -P. The experimental results were supported by computational studies.