Partic. vol. 14 pp. 24-32 (June 2014)
doi: 10.1016/j.partic.2013.04.002

In situ synthesis of CNTs/Fe–Ni/TiO2 nanocomposite by fluidized bed chemical vapor deposition and the synergistic effect in photocatalysis

Lei Ma, Aiping Chen^*, Jindong Lu, Zhe Zhang, Hongbo He, Chunzhong Li

apchen@ecust.edu.cn

Abstract

Carbon nanotube (CNTs)/Fe–Ni/TiO₂ nanocomposite photocatalysts have been synthesized by an in situ fluidized bed chemical vapor deposition (FBCVD) method. The composite photocatalysts were characterized by XRD, Raman spectroscopy, BET, FESEM, TEM, UV–vis spectroscopy, and XPS. The results showed that the CNTs were grown in situ on the surface of TiO₂. Fe(III) in TiO₂ showed no chemical changes in the growth of CNTs. Ni(II) was partly reduced to metal Ni in the FBCVD process, and the metal Ni acted as a catalyst for the growth of CNTs. The photocatalytic activities of CNTs/Fe–Ni/TiO₂ decreased with the rise of the FBCVD reaction temperature. For the sample synthesized at low FBCVD temperature (500 °C), more than 90% and nearly 50% of methylene blue were removed under UV irradiation in 180 min and under visible light irradiation in 300 min, respectively. The probable mechanism of synergistic enhancement of photocatalysis on the CNTs/Fe–Ni/TiO₂ nanocomposite is proposed.

Graphical abstract

Keywords

CNTs/Fe–Ni/TiO₂; In situ FBCVD method; Photocatalytic degradation; Synergistic effect