Preparation of High Catalytic Platinum Hollow Nanospheres and Their Electrocatalytic Performance for Methanol Oxidation

Pt hollow nanospheres with a particle diameter of 110 nm and a shell thickness of about 5 nm were synthesized in bulk using selenium colloids with a particle diameter of 100 nm as a template. Transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), energy dispersive X-ray spectrocopy (EDX), and scanning electron microscopy (SEM) were used to determine their morphologies and structures. The electrocatalytic activity of the Pt hollow nanospheres modifying glassy carbon electrode toward methanol oxidation was measured by using methanol as the probe molecule. We show that the multiporous Pt hollow nanospheres composited of atomic clusters have a uniform particle size, good dispersity, a stable structure, a big surface area and good mass transfer performance. Cyclic voltammetry (CV) showed that when the current density of methanol oxidation was 0.10 mA.cm(-2) and upon positive scanning the methanol oxidation potential of the Pt hollow nanospheres was around 110 and 64 mV negative than that of the Pt solid nanoparticles and Pt black, respectively. Upon negative scanning the former species was about 51 and 13 mV negative than that of the latter two species, respectively. After 800 segments cyclic voltammetry scanning, upon positive scanning the peak current density of methanol oxidation on the Pt hollow nanospheres was found to be 13 and 15 times as high as that of the Pt solid nanoparticles and Pt black, respectively. Upon negative scanning the former species was about 19 and 38 times as high as that of the two latter species. Our experimental results show that the Pt hollow nanospheres have good electrocatalytic activity and stability toward methanol oxidation.