Di-ureasil ormolytes doped with Mg2+ ions: Part 1: Morphological, thermal and electrochemical properties

Poly(oxyethylene) (POE)/siloxane-based materials incorporating magnesium triflate (Mg(CF3SO3)2) were synthesized by the sol–gel process. The host Class II hybrid matrix (di-ureasil) employed is composed of a siliceous framework to which short POE chains are covalently bonded through urea linkages. Ormolytes with salt composition n (molar ratio of oxyethylene moieties per Mg2+ ion) ranging from ∞ to 1 were investigated. The nanohybrid with n = 20, which is thermally stable up to 360 °C, exhibits the highest conductivity (e.g., approximately 4.0 × 10− 6 and 6.7 × 10− 5 S cm− 1 at 35 and 104 °C, respectively). The redox stability domain of this material spans from − 3.0 to + 2.0 V vs. Mg/Mg2+.