CNTs-TiO 2¯l ms with di®erent morphology were fabricated on stainless steel substrates through chemical vapor hydrolysis deposition (CVHD) process and sol-gel process, respectively. Their morphology was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The photocatalytic properties of the¯lms were tested in the degradation of methyl orange by UV light irradiation. The results revealed that TiO 2 nanoparticles could form a continuous layer on the surface of CNTs through CVHD process. While for sol-gel process, most TiO 2 nanoparticles were isolated and only a small amount of TiO 2 nanoparticles attached on the surface of CNTs. And the photocatalytic property of TiO 2 /CNTs¯lm synthesized through CVHD process was better than that of TiO 2 /CNTs¯lms synthesized through sol-gel process. Electrochemical impedance spectroscopy (EIS) analysis illuminated that TiO 2 /CNTs synthesized through CVHD process displayed a smaller resistance than the sample which was synthesized through sol-gel process and certi¯ed that the close combination between TiO 2 and CNTs could minimize recombination of photogenerated electrons and holes, and thus promote the photocatalytic property.

High-performance carbon nanotubes-supported Pt catalysts (Pt/CNTs) catalysts were prepared on the basis of Pt precursors reduced by hydrogen plasma (Pt/CNTs-HP) generated by microwave. The other two Pt/CNTs catalysts prepared by hydrogen (Pt/CNTs-H) and NaBH 4 (Pt/CNTs-N) reduction were also involved for comparison. The practical composition of the catalysts was characterized with energy dispersive analysis of X-ray (EDAX). It was shown from transmission electron microscopy (TEM) and X-ray di®raction (XRD) that the Pt nanoparticles in Pt/CNTs-HP were uniformly dispersed on CNTs with smaller particle size around 2 nm and narrower size distribution as compared with the other two catalysts. Additionally, X-ray photoelectron spectrum (XPS) analysis indicated higher amount of zero-valence states of Pt in Pt/CNTs-HP caused by hydrogen plasma treatment. The electrooxidation of liquid methanol on these catalysts was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and chronoamperometry. The long-time durability is very comparable to all the three catalysts. Remarkably, the Pt/CNTs-HP possessed the highest electrocatalytic activity, suggesting that the hydrogen plasma reduction approach can be a promising reduction method for preparing high-performance Pt-based electrocatalysts.

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