Balázs Réti

Photocatalytic hollow TiO 2 and ZnO nanospheres prepared by atomic layer deposition

Carbon nanospheres (CNSs) were prepared by hydrothermal synthesis, and coated with TiO2 and ZnO nanofilms by atomic layer deposition. Subsequently, through burning out the carbon core templates hollow metal oxide nanospheres were obtained. The substrates, the carbon-metal oxide composites and the hollow nanospheres were characterized with TG/DTA-MS, FTIR, Raman, XRD, SEM-EDX, TEM-SAED and their photocatalytic activity was also investigated. The results indicate that CNSs are not beneficial for photocatalysis, but the crystalline hollow metal oxide nanospheres have considerable photocatalytic activity.

Core-shell carbon nanosphere-TiO2 composite and hollow TiO2 nanospheres prepared by atomic layer deposition

Core-shell carbon-TiO2 composite and hollow TiO2 nanospheres were prepared using carbon nanospheres as hard-templates, coating them with TiO2 using atomic layer deposition, and subsequent burning out of the carbon cores. The bare carbon, the composite carbon-TiO2 and the hollow TiO2 nanospheres were characterized with TG/DTA-MS, FTIR, XRD and SEM-EDX.

Preparing SnO2/MWCNT Nanocomposite Catalysts via High Energy Ball Milling

Ball milling method was used to fabricate successfully tin dioxide (SnO₂)/multi-walled carbon nanotubes nanocomposite materials using SnCl₂ ×2H₂O as precursor together with soda and salt as admixture. The as-prepared materials were characterized by transmission electron microscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, Raman microscopy, and X-ray diffraction techniques. Observations revealed that applying both soda and salt are advantageous for increasing dispersity of tin dioxide nanoparticles on the surface of carbon nanotubes. These multi-walled carbon nanotube-based composites are promising candidates as thick film gas sensors or catalysts. Results indicate that SnO₂/MWCNT composites can be achieved under solvent free dry conditions, too.

Modification of mechanical properties of polymers by SiO2 - MgO coated multiwalled carbon nanotubes

Multiwalled carbon nanotubes (MWCNTs) feature excellent mechanical properties and for this reason these nanomaterials are suitable candidate for a reinforcement material in the polymer composites. To take full advantage of their outstanding properties, homogeneous distribution needs to be improved in the polymer matrix. In the following study multi-walled carbon nanotubes were coated with SiO2-MgO nanoparticles - to improve the interfacial bonding between the MWCNTs and the matrix - and dispersed in two different polymers. The influence of the coated MWCNTs on mechanical properties was investigated by dynamic mechanical analysis (DMA), and tensile test. We have observed experimentally that mutual chemical connection between the inorganic layer on the MWCNTs and polymer matrix can enhance the properties of the polymers.