Controlled Assembly of a Dawson-like Antimoniotungstate-Supported Trefoil-type Trimer with Good Proton Conductivity Performance

Abstract

With the excellent properties of POM in the field of proton conductivity, the preparation of POM-based proton-conductive materials has burst into life. Herein, an unprecedented Sb-templated all-inorganic trimer Na 8 H 18.64 [(SbW 14 O 52 ) 3 (Sb 2 W 6.12 Ru 5.88 O 18 )]•85H 2 O (1), which is based on tetravacant Dawson-like [SbW 14 O 52 ] 17− blocks and exhibits a trefoil type with D 3 symmetry, has been successfully designed and synthesized by the assembly of simple materials with a one-pot hydrothermal method under acidic conditions. Also, compound 1 is systematically characterized by singlecrystal X-ray diffraction, PXRD, ESI-MS, IR spectroscopy, UV−vis, elemental analysis, and TGA. Crystal structure data analysis demonstrates that compound 1 is constructed by a hexagonal prismatic heterometallic {Sb 2 W 6.12 Ru 5.88 O 18 } core and three equivalent {SbW 14 } units bridged through μ 2 -O atoms in periphery. Subsequently, further property experiments show that compound 1 exhibits high proton conductivity with a conductivity value (σ) of 3.07 × 10 −2 S cm −1 at 75 °C and 80% relative humidity (RH). The activation energy of compound 1 evaluated by the Arrhenius plots is 0.22 eV, which indicates that the Grotthuss mechanism is dominant during the process of proton transfer.