Platinum (Pt) is the most promising catalyst for hydrogen oxidation and oxygen reduction. However, the residual surface-stabilizing agents capped on Pt-based nanomaterials via traditional chemical approaches will significantly reduce their catalytic activity. Herein, a new one-step strategy for the facile synthesis of surfactant-free Pt nanospheres with clean surface structures is developed by laser ablation of Pt target in distilled water. The distinctive advantage is that the pure water-dispersed Pt nanospheres can be obtained without any extra purification procedures, and the obtained catalyst exhibits enhanced electrocatalytic activity compared with Pt nanospheres capped with polyvinyl pyrrolidone or cetyl trimethyl ammonium bromide, which are most regular stabilizers or surfactants in traditional nanoparticles synthesis method. Importantly, the mass-normalized cyclic voltammetry (CV) curves for the methanol oxidation reaction show that the measured value of peak current is nearly 610 and 1050 times higher than that of Pt/PVP and Pt/CTAB samples. Moreover,the chronoamperometric (CA) measurements reveals that the steady-state current density is about 1.28 mA/cm2, while which of Pt/PVP and Pt/CTAB are 1.07 and 0.017 μA/cm2, respectively. It is no doubt that the application of laser beam as an environmental friendly tool for sculpting pure functional metal-based nanomaterials is a breakthrough in the additive problems that arise from standard chemical fabrication.
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