One-Pot and Surfactant-Free Synthesis of Ultrafine PtSn Nanoparticles Supported on Onion-Like Nanocarbons Toward Efficient Methanol and Ethylene Glycol Oxidation Reactions.

New synthetic method toward carbon supported catalysts with improved performance is of great importance in direct alcohol fuel cells (DAFCs). Herein, onion-like nanocarbons (OLNCs) were fabricated by using cheap and readily available candle as the raw material. And a facile one-pot and surfactant-free solvothermal approach was developed for the fabrication of PtSn nanoparticles supported on the OLNCs. Transmission electron microscopy (TEM) images showed the highly crystalline PtSn nanoparticles with size of similar to 2-5 nm were evenly deposited on the surface of the OLNCs. The obtained PtSn/OLNCs nanocomposites with Pt loading of about 10.1% exhibited excellent electrocatalytic activity toward both methanol oxidation reactions (MOR) and ethylene glycol oxidation reactions (EGOR). The current density of PtSn/OLNCs is 2.6 and 2.7 times of the commercial 20 wt% Pt/C toward the MOR and EGOR, respectively, suggesting the great application potential of the PtSn/OLNCs catalyst in DAFCs. The highly electrocatalytic activity of the PtSn/OLNCs may arise from the ultra-small size of the PtSn NPs as well as the large surface area and good electric conductivity of the OLNCs support. This study not only provides an example of the cost-effective fabrication and application of the OLNCs based catalysts and also sheds a new light on the application of the PtSn/OLNCs catalyst in DAFS.