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Electrolytes based on a poly(!-caprolactone) (PCL)/siloxane organic/inorganic host framework doped with lithium triflate (LiCF 3 SO 3 ) were synthesized through the sol-gel process. In this biohybrid matrix short PCL chains are covalently bonded via urethane linkages to the siliceous network. Samples with salt composition n (molar ratio of PCL repeat units per Li + ion) ranging from " to 0.5 were investigated. All the ormolyte materials analyzed are amorphous. Xerogels with n > 0.5 are thermally stable up to about 300 ºC. The most conducting ormolyte of the series is that with n = 0.5 (1.6x10 -7 and 3.2x10 -5 # -1 cm -1 at 25 and 100 ºC, respectively).

Poly(oxyethylene) (POE)/siloxane-based materials incorporating magnesium triflate (Mg(CF 3 SO 3) 2) were synthesized by the sol-gel process. The host Class II hybrid matrix (diureasil) 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 Mg 2+ ion) ranging from ! to 1 were investigated. The nanohybrid with n = 20, which is thermally stable up to 360 ºC, exhibits the highest conductivity (e.g., approximately 4.0x10-6 and 6.7x10-5 "-1 cm-1 at 35 and 104 ºC, respectively). The redox stability domain of this material spans from-3.0 to +2.0 V versus Mg/Mg 2+ .

Here we summarize some results on the use of TiO nanostructures as anode materials for more efficient Li-ion (LIBs) and Na-ion (NIBs) batteries. LIBs are the leader to power portable electronic devices, and represent in the short-term the most adequate technology to power electrical vehicles, while NIBs hold promise for large storage of energy generated from renewable sources. Specifically, TiO an abundant, low cost, chemically stable and environmentally safe oxide represents in LIBs an alternative to graphite for applications in which safety is mandatory. For NIBs, TiO anodes (or more precisely negative electrodes) work at low voltage, assuring acceptable energy density values. Finally, assembling different TiO polymorphs in the form of nanostructures decreases diffusion distances, increases the number of contacts and offering additional sites for Na storage, helping to improve power efficiency. More specifically, in this contribution we highlighted our work on TiO anatase mesocrystals of colloidal size. These sophisticate materials; showing excellent textural properties, have remarkable electrochemical performance as anodes for Li/Na-ion batteries, with conventional alkyl carbonates electrolytes and safe electrolytes based on ionic liquids.