In this work, we present the growth and optical characterization of carbon nanotube/TiO2 anatase nanocomposites. The composites are obtained by doping a bulk of anatase nanometric grains with different weight percenta...In this work, we present the growth and optical characterization of carbon nanotube/TiO2 anatase nanocomposites. The composites are obtained by doping a bulk of anatase nanometric grains with different weight percentages of carbon nanotube (from 0.1% to 50%). We observe that only for tube concentrations between 0.1% and 2%, the growth process shows the formation of a matrix where carbon nanotubes are uniformed and dispersed in a bulk of TiO2 grains. Moreover, the X-ray photoelectron spectroscopy and surface morphology analysis (conducted from AFM images) indicated that the CNT absorption is a simple physisorption without chemical bonds formations between tube and dioxide. Finally, absorption in all the visible range has the increase of about 60% at very low concentration (2%) of carbon nanotubes.展开更多
In this work, we present a study of growth and characterization of nanocomposites, based on multiwalled carbon nanotubes and metal nanoparticles (Al, Ag, Au, Co, Cu, Fe, Ni and Ti). We observe a very different behavio...In this work, we present a study of growth and characterization of nanocomposites, based on multiwalled carbon nanotubes and metal nanoparticles (Al, Ag, Au, Co, Cu, Fe, Ni and Ti). We observe a very different behavior between noble and transitions metals. All the nanocomposites are characterized by a network of carbon nanotubes with randomly insertion of spherical metal particles with dimensions of about 100 nm (clearly visible in SEM images). In particular, in transition metal nanocomposites, each tube on sheet surface is covered by particles of about 40 - 50 nm and for all metals the XPS measurements indicate the absence of chemical bonds and the simply physisorption of nanoparticle on carbon nanotube buckypaper. Furthermore, the nanocomposites show very different properties respect to pure carbon nanotubes: they are hydrophobic, their roughness is about 50% smaller than carbon nanotube and they exhibit a strong visible photoluminescence, which is absent in pure nanotube.展开更多
文摘In this work, we present the growth and optical characterization of carbon nanotube/TiO2 anatase nanocomposites. The composites are obtained by doping a bulk of anatase nanometric grains with different weight percentages of carbon nanotube (from 0.1% to 50%). We observe that only for tube concentrations between 0.1% and 2%, the growth process shows the formation of a matrix where carbon nanotubes are uniformed and dispersed in a bulk of TiO2 grains. Moreover, the X-ray photoelectron spectroscopy and surface morphology analysis (conducted from AFM images) indicated that the CNT absorption is a simple physisorption without chemical bonds formations between tube and dioxide. Finally, absorption in all the visible range has the increase of about 60% at very low concentration (2%) of carbon nanotubes.
文摘In this work, we present a study of growth and characterization of nanocomposites, based on multiwalled carbon nanotubes and metal nanoparticles (Al, Ag, Au, Co, Cu, Fe, Ni and Ti). We observe a very different behavior between noble and transitions metals. All the nanocomposites are characterized by a network of carbon nanotubes with randomly insertion of spherical metal particles with dimensions of about 100 nm (clearly visible in SEM images). In particular, in transition metal nanocomposites, each tube on sheet surface is covered by particles of about 40 - 50 nm and for all metals the XPS measurements indicate the absence of chemical bonds and the simply physisorption of nanoparticle on carbon nanotube buckypaper. Furthermore, the nanocomposites show very different properties respect to pure carbon nanotubes: they are hydrophobic, their roughness is about 50% smaller than carbon nanotube and they exhibit a strong visible photoluminescence, which is absent in pure nanotube.
