Synthesis of {AlMo<sub>14</sub>O<sub>44</sub>}‑Based\nSupramolecular Structures with High Proton Conductivity

Polyoxometalates (POMs) are esteemed\nfor their remarkable stability\nand exceptionally high proton conductivity, rendering them ripe for\nextensive exploration owing to their research significance. Herein,\nwe synthesized two bimolybdenum-capped {AlMo<sup>VI</sup><sub>8</sub>Mo<sup>V</sup><sub>6</sub>O<sub>44</sub>} cluster-based coordination\npolymers through a solvothermal method. Single-crystal X-ray diffraction\nanalysis elucidates that H[(H<sub>2</sub>bimb)<sub>3</sub>(AlMo<sup>VI</sup><sub>8</sub>Mo<sup>V</sup><sub>6</sub>O<sub>44</sub>)] [bimb\n= 1,4-bis(imidazole-1-ylmethyl)benzene, compound <b>1</b>] is\nthe POMs-organic supramolecular structure. The introduction of zinc\nions into the reaction environment facilitated the connection of initially\ndispersed ligands, which yielded the well-ordered structure H<sub>3</sub>[Zn<sub>2</sub>(bimb)<sub>4</sub>(AlMo<sup>VI</sup><sub>8</sub>Mo<sup>V</sup><sub>6</sub>O<sub>44</sub>)]·4H<sub>2</sub>O (compound <b>2</b>) with a layer distance of 11.8 Å. The proton conductivities\n(σ) of two compounds were measured under conditions of 85 °C\nand 98% relative humidity (RH), resulting in values of 3.89 ×\n10<sup>–2</sup> and 4.76 × 10<sup>–2</sup> S·cm<sup>–1</sup>, respectively. This study presents a novel approach\nto fabricating POMs as proton conductors through structural design\nand manufacturing adjustments.