Two new 1-D and 3-D Wells–Dawson structures assisted by alkali metals

Abstract

Two new Wells–Dawson based compounds containing alkali metals, [Ag(H₂biim)₂]₂·[Ag₅(H₂biim)₁₀Na₂(H₂O)₂(H_3/2P₂W₁₈O₆₂)₂]·12H₂O (1) and [Cd(H₂biim)₂ K(P₂W₁₈O₆₂)_1/2] (2) (H₂biim = 2,2′-biimidazole), have been synthesized under hydrothermal conditions. In 1, two-supporting Wells–Dawson anions are linked by a [Ag(H₂biim)₂]⁺ subunit to form a dimer. The adjacent dimers are further connected by Na⁺ through (POM)O-Na-O(POM) bonds to build a 1-D chain. In 2, adjacent anions are linked by two [Cd₂(H₂biim)₂]⁴⁺ subunits and a 1-D chain is formed. Furthermore, the anion in the chain is fused by six K⁺ ions and a 3-D framework is obtained. The alkali metals exhibit crucial influence on the conversion of dimensionality assisting anions and Ag-H₂biim subunits to construct 1-D and 3-D frameworks. The electrochemical and photocatalytic properties of 1 and 2 have been investigated.

Graphical Abstract

Keywords:

• Wells–Dawson polyoxometalate
• Alkali metals
• Hydrothermal synthesis
• Electrochemical property
• Photocatalytic properties

Funding

This work was supported by the National Natural Science Foundation of China [grant numbers 21101015, 21171025, and 21201021]; the Program for New Century Excellent Talents in University [NCET-09-0853]; the Program of Innovative Research Team in University of Liaoning Province [LT2012020]; Doctoral Initiation Project [grant number 20111147] of Liaoning Province and Talent-supporting Program Foundation of Education Office of Liaoning Province [LJQ2012097].