Conference: E-MRS ICAM IUMRS 2011 Spring Meeting
February 8, 2013
Date: 9- 13 may 2011
Place: Nice, France
Speakers IMDEA Energía: Teresa González de Chávez Capilla
More information: http://bit.ly/ePXT8a
Oral Presentation: Synthesis of TiO2/V2O5 core/shell nanocrystals for supercapacitors
The integration of renewable energy sources to the electrical grid and the implementation of electric transport require new energy storage devices with much higher energy densities. This challenge is particularly important for supercapacitors, which typically have very high power densities but energy densities much lower than most batteries. Several approaches are being pursued nowadays in order to increase the energy density of current supercapacitors, and nanomaterials are expected to become crucial in future devices. Additional benefits are expected when complex structures with complementary properties are combined. We have developed a new sol-gel synthetic strategy in order to obtain TiO2/V2O5 nanocrystals which have been characterized with HRTEM, XPS, XRD, and ICP. Amorphous titania nanoparticles were prepared by low temperature sol-gel processing of TiCl4-derived solutions in dodecylamine. Then the required amount of VCl4-derived precursor was added to the TiO2 suspension, followed by solvothermal processing in oleic acid at 250 oC. Results show the small TiO2 nanocrystal size (about 4 nm) with narrow dispersion and the crystalline nature of the materials obtained, as well as the presence of VOx on the shell of the nanocrystals. This particular combination of materials has been designed as a new concept of oxide/oxide materials for supercapacitors, and performances are improved by one order of magnitude after 1000 cycles compared to each one of the two oxides.
