Syntheses, Structural Characterization, and Catalytic Properties of Di- and Trinickel Polyoxometalates

The syntheses, structural characterization, and catalytic properties of two different nickel-containing polyoxometalates (POMs) are presented. The dinickel-containing sandwich-type POM [Ni₂(P₂W₁₅O₅₆)₂]^20– (<b>Ni</b>_<b>2</b>) exhibits an unusual αααα geometry. The trinickel-containing Wells–Dawson POM [Ni₃(OH)₃(H₂O)₃P₂W₁₆O₅₉]^9– (<b>Ni</b>_<b>3</b>) shows a unique structure where the [α-P₂W₁₅O₅₆]^12– ligand is capped by a triangular Ni₃O₁₃ unit and a WO₆ octahedron. <b>Ni</b>_<b>3</b> shows a high catalytic activity for visible-light-driven hydrogen evolution, while the activity for <b>Ni</b>_<b>2</b> is minimal. An analysis of the structures of multinickel-containing POMs and their hydrogen evolution activity is given

Syntheses, Structural Characterization, and Catalytic Properties of Di- and Trinickel Polyoxometalates

The syntheses, structural characterization, and catalytic properties of two different nickel-containing polyoxometalates (POMs) are presented. The dinickel-containing sandwich-type POM [Ni₂(P₂W₁₅O₅₆)₂]^20– (<b>Ni</b>_<b>2</b>) exhibits an unusual αααα geometry. The trinickel-containing Wells–Dawson POM [Ni₃(OH)₃(H₂O)₃P₂W₁₆O₅₉]^9– (<b>Ni</b>_<b>3</b>) shows a unique structure where the [α-P₂W₁₅O₅₆]^12– ligand is capped by a triangular Ni₃O₁₃ unit and a WO₆ octahedron. <b>Ni</b>_<b>3</b> shows a high catalytic activity for visible-light-driven hydrogen evolution, while the activity for <b>Ni</b>_<b>2</b> is minimal. An analysis of the structures of multinickel-containing POMs and their hydrogen evolution activity is given