Highly ordered hierarchical Pt and PtNi nanowire arrays were prepared using CdS hierarchical nanowire arrays (HNWAs) as sacrificial templates and demonstrated high electrochemical active surface areas. For the resulting Pt HNWAs sample, the peak current for methanol oxidation at +0.74 V was almost 1 order of magnitude higher than that of Pt solid nanowire arrays prepared in a similar manner but without the use of CdS template, and the addition of a Ni cocatalyst effectively enhanced the tolerance against CO poisoning. The results demonstrated that highly ordered Pt and PtNi HNWAs may be exploited as promising anode catalysts in the application of direct methanol fuel cells.

To enhance the microbial fuel cell (MFC) for wastewater treatment and chemical oxygen demand degradation, TiO 2 nanotubes arrays (TNA) are successfully synthesized on Ti foil substrate by the anodization process in HF and NH 4 F solution, respectively (hereafter, denoted as TNA‐HF and TNA‐NF). The differences between the two kinds of TNA are revealed based on their morphologies and spectroscopic characterizations. It should be highlighted that 3D TNA‐NF with an appropriate dimension can make a positive contribution to the high photocatalytic activity. In comparison with the TNA‐HF, the 3D TNA‐NF sample exhibits a significant enhancement in current generation as the MFC anode. In particular, the TNA‐NF performs nearly 1.23 times higher than the TNA‐HF, and near twofold higher than the carbon felt. It is found that the two kinds of TiO 2 ‐based anodes have different conductivities and corrosion potentials, which are responsible for the difference in their current generation performances. Based on the experimental results, excellent stability, reliability, and low cost, TNA‐NF can be considered a promising and scalable MFC bioanode material.

AuPt nanoparticles clusters (NPCs) were electrodeposited on multiwalled carbon nanotubes (MWCNTs). The as-prepared AuPt NPCs@MWCNTs nanocomposites exhibited considerably enhanced electrocatalytic activity than Pt NPs@MWCNTs for methanol oxidation in acid medium. In comparison with Pt NPs@MWCNTs, a remarkable resistance to CO poisoning and a higher If/Ib value (the ratio of the forward scan oxidation peak current (If) and reverse scan oxidation peak current (Ib)) was achieved by AuPt NPCs@MWCNTs electrocatalyst, which is attributable to the unique NPCs nanostructure with enlarged electrochemical active surface areas. These results demonstrated the potential of AuPt NPCs@MWCNTs, which can be considered as an efficient electrocatalyst for methanol oxidation in direct methanol fuel cells.

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