Nanotubos de TiO2 auto-organizados como material de electrodo para microbaterías de ión litio

II Encuentro sobre nanociencia y nanotecnología de investigadores y tecnólogos de la Universidad de Córdoba. NANOUC

High Li+ and Na+ Conductivity in New Hybrid Solid Electrolytes based on the Porous MIL-121 Metal Organic Framework

Solid-state electrolytes (SSEs) can leapfrog the development of all-solid-state batteries (ASSBs), enabling them to power electric vehicles and to store renewable energy from intermittent sources. Here, a new hybrid Li+ and Na+ conducting SSE based on the MIL-121 metal-organic framework (MOF) structure is reported. Following synthesis and activation of the MOF, the free carboxylic units along the 1D pores are functionalized with Li+ or Na+ ions by ion exchange. Ion dynamics are investigated by broadband impedance spectroscopy and by Li-7 and Na-23 NMR spin-lattice relaxation. A crossover at 50 degrees C (Li+) and at 10 degrees C (Na+) from correlated to almost uncorrelated motion at higher temperature is observed, which is in line with Ngai\u27s coupling model. Alternatively, in accordance to the jump relaxation model of Funke, at low temperature only a fraction of the jump processes are successful as lattice rearrangement in the direct vicinity of Li+ (Na+) is slow. H-1 NMR unambiguously shows that Li+ is the main charge carrier. Conductivities reach 0.1 mS cm(-1) (298 K, Na+) while the activation energies are 0.28 eV (Li+) and 0.36 eV (Na+). The findings pave the way towards development of easily tunable and rationally adjustable high-performance MOF-based hybrid SSEs for ASSBs

Nano-hilos de Sn y SnO crecidos sobre láminas de nano-tubos de TiO2 como electrodos de batería de ion-Li

III Encuentro sobre Nanociencia y Nanotecnología de Investigadores y Tecnólogos Andaluce

Nanostructured Ceramics: Ionic Transport and Electrochemical Activity

Ceramics with nm-sized dimensions are widely used in various applications such as batteries, fuel cells or sensors. Their oftentimes superior electrochemical properties as well as their capabilities to easily conduct ions are, however, not completely understood. Depending on the method chosen to prepare the materials, nanostructured ceramics may be equipped with a large area fraction of interfacial regions that exhibit structural disorder. Elucidating the relationship between microscopic disorder and ion dynamics as well as electrochemical performance is necessary to develop new functionalized materials. Here, we highlight some of the very recent studies on ion transport and electrochemical properties of nanostructured ceramics. Emphasis is put on TiO2 in the form of nanorods, nanotubes or being present as mesoporous material. Further examples deal with nanocrystalline peroxides such as Li2O2 or nanostructured oxides (Li2TiO3, LiAlO2, LiTaO3, Li2CO3 and Li2B4O7). These materials served as model systems to explore the influence of ball-milling on overall ionic transport