Highly crystalline PtCu nanotubes with three dimensional molecular accessible and restructured surface for efficient catalysis
Direct methanol fuel cells (DMFCs) as candidates for the dominant energy conversion devices basing on the higher energy densities of the liquid methanol show unique advantages over hydrogen-based fuel cells, such as cheap, easily storing and transportation. However, the fundamental challenges for electrochemical oxidation of methanol are the sluggish electro-oxidation kinetics and recovering of Pt surface to lower costs. Here, we report a mixed solvent strategy to prepare a highly active and durable class of electrocatalysts with connected single crystalline nanoparticles (NPs), forming open architecture. Each single crystalline NP along the PtCu nanotubes (NTs) can be considered as a high active unit with specific facet and assembles along one dimensional (1D) direction. The Pt1Cu1-AA NTs achieves a factor of 5.5 and 10.3 enhancement in mass activity (2252 mA mg-1) and specific activity (6.09 mA cm-2) for methanol oxidation reaction (MOR) relative to Pt/C catalysts, respectively. Moreover, after a long term stability tests, the activity of the NTs could be recovered via a simple potential cycling process (reactivation process) to the initial value or be better, thus this kind of catalysts would limit the costs to the initial investment and recovery and show potential possibility in real DMFC devices.