Conductive Inorganic–Organic Hybrid Layered Crystals Composed of Keggin‐Type Polyoxotungstates and a Heterocyclic Surfactant

Keggin‐type polyoxotungstate hybrid layered crystals are successfully synthesized in a single phase by using a heterocyclic surfactant. Heteropolyoxotungstate anions of [XW12O40]n– (XW12, X = P, Si; n = 3, 4) are hybridized with the dodecylpyridazinium (C12pda) cation. Single‐crystal X‐ray diffraction analyses reveal that all of the countercations of XW12 are replaced by C12pda cations. The layered structures consist of XW12 inorganic layers and C12pda organic layers, stacked alternately. In the PW12 hybrid crystal (1), the PW12 anions form a bilayer structure, comprising a one‐dimensional infinite chain of PW12 connected through short contacts. The SiW12 hybrid crystal (2) contains SiW12 monolayers isolated by heterocyclic moieties of the C12pda cations. The conductivity of 1, under an anhydrous atmosphere, is estimated to be 2.5 × 10–8 S cm–1 at 373 K, while the hybrid crystal 2 exhibits a maximum conductivity of 1.1 × 10–4 S cm–1 at 453 K. Keggin‐type polyoxotungstates, [PW12O40]3– (PW12) and [SiW12O40]4– (SiW12), are hybridized with the heterocyclic dodecylpyridazinium (C12pda) cation to obtain conductive layered crystals in a single phase. The conductivities are estimated to have a maximum value of 1.1 × 10–4 S cm–1 for the SiW12 hybrid crystal.