Abstract (EN):
Vertically aligned carbon nanotubes (VA-CNTs) of 2.3 mu m in height were produced by thermal chemical vapor deposition (TCVD) on Si/SiO2 substrates. These carbon arrays were coated with zinc oxide (ZnO) via atomic layer deposition (ALD) technique. Conformal, uniform and very thin films (max. 26 nm) around the CNTs were obtained after 200 ALD cycles. The photocatalytic performance of these nanocomposite materials was tested in the degradation of rhodamine B, a harmful dye present in food and textile wastewaters. The optimal degradation performance is already obtained after 100 ALD cycles on VA-CNTs, which provide 77 % of RhB degradation after 420 min of irradiation. The photocatalytic results suggested a remarkable synergistic effect between the CNT and ZnO phases. The stability of ZnO/CNTs nanocomposites after being used as photocatalysts was demonstrated by Raman spectroscopy, as the CNTs structure stayed intact and the ZnO remained coupled to the CNTs. Thus, a main advantage of the present approach is the immobilization of the photocatalyst material on a solid support, avoiding further complex nanomaterial separation from the treated water stream.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
8