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This report presents detailed studies on the morphology, thermal stability, and electrical spectroscopy of 11 aluminum-containing hybrid inorganic-organic polymer electrolytes with the general formula ͕Al͓O͑CH 2 CH 2 O) 8.7 ] /(LiClO 4 ) z ͖ n , where 1.85 р р 2.24 and 0 р z р 1.06. Scanning electron microscopy showed a solid-plastic appearance and a smooth texture on the surface of the bulk materials. Thermogravimetric investigations indicated that the hybrid polymer electrolytes are thermally stable up to ϳ260°C. Furthermore, a detailed study of the mechanism of ion conduction in these systems was carried out by impedance spectroscopy in the 20 Hz to 1 MHz range and at temperatures varying from 18 to 80°C. It was demonstrated that the ͕Al͓O͑CH 2 CH 2 O) 8.7 ] /(LiClO 4 ) z ͖ n materials conduct ionically by a charge-transfer mechanism mainly regulated by segmental motion and fast ion-hopping processes between equivalent coordination sites distributed along polyether chains. The ''anion trapping'' ability of the aluminum atoms toward perchlorate contributes greatly to the conductivity performance of the ͕Al͓O͑CH 2 CH 2 O) 8.7 ] /(LiClO 4 ) z ͖ n networks. Finally, the best conductivity observed in these materials is 1.66 ϫ 10 Ϫ5 S cm Ϫ1 at 25°C.

Eleven new aluminum-based organically modified ceramics as polymer electrolytes were prepared and characterized. The hybrid inorganic-organic networks with the general formula ͕Al͓O͑CH 2 CH 2 O) 8.7 ] /(LiClO 4 ) z ͖ n , where 1.85 р р 2.24 and 0 р z р 1.06, were prepared by a polycondensation reaction starting from aluminum isopropoxide and poly͑ethylene glycol͒ (PEG400)/(LiClO 4 ) y liquid polymer electrolytes with 0 р y р 0.49. Detailed compositional data, Fourier transform infrared ͑FTIR͒, and FT-Raman investigations allowed us to propose a structural hypothesis for this class of materials and to characterize the interactions between ions and binding sites in the host networks. These materials present a glassy rubbery consistency and consist of Al atoms bonded together by PEG400 bridges. Medium FTIR and FT-Raman studies of the polymers showed that the polyether moieties exhibit a TGT ͑T trans, G gauche͒ conformation with helical geometry and detected the presence of Li ϩ ¯ClO 4 Ϫ ¯Al͓O͑CH 2 CH 2 O) 8.7 ] 3 neutral species at c Li 1/2 у 0.4 ͑mol kg Ϫ1 ͒ 1/2 . We verified that in bulk ͕Al͓O͑CH 2 CH 2 O) 8.7 ] /(LiClO 4 ) z ͖ n complexes the acid aluminum cross-linking sites exhibit the anion trapping phenomenon toward perchlorate anions.