Preparation and Characterization of Poly(ionic Liquids)/Pt Nanoparticle Hybrids
|Keywords||Ionic Liquid Pt nanoparticles Graphited carbon material Methanol Catalysts|
Ionic liquids (ILs) are organic salts with melting points at or near room temperature. They are attracting much interest in manyfields of chemistry and industry because of their chemical stability, thermal stability, nonvolatility and high ionic conductivity. These properties of ILs qualify them as alternatives to traditional organic solvents, and ILs have already found use in organic/inorganic synthesis, catalysis, electrosynthesis, and polymer synthesis. ILs can provide highly polar environments for materials synthesis. The synthesis of novel nanostructures in ILs has recently been gradually realized.Due to their good stability, the quantum size effect,the surface and optics effect,and the special affinity for biology molecules, noble metal nanoparticles have shown promising application in the fields of catalysis, optics, electronics and biology sensor, etc. How to prepare even dispersed Pt nanoparticles catalyst with small particle size and improve the catalytic activity and use the environment-friendly solvent (e. g., H2O2 and aqueous solution) in the reactions are still important and challenging. Take the above ideas into account, we synthesized a serious of nanoparticle hybridsbased on ionic liquids, the main contents are as follows:1. The well dispersed PIL nanoparticles with the diameter of about 200 nm were synthesized by mini-emulsion polymerization, and the morphology was characterized .2. We synthesized the PIL-Pt and PIL-Au nanoparticle hybrids which Pt and Au nanoparticles were well dispersed on the surface, and the structure and morphology were characterized, respectively. The catalytic performances of PIL-Pt nanoparticle hybrids were evaluated for both the electrocatalytic oxidation of methanol and oxidation of benzyl alcohol. The results are as follows: the PIL-Pt nanoparticle hybrids show better electrocatalytic activity (115 mAmg-1 for PIL, while 21mAmg-1 for pure Pt) and stability than pure Pt nanoparticles; the PIL-Pt nanoparticle hybrids are effective(conversion:92%, selectivity:100%) and easily reusable catalysts for the selective oxidation of benzyl alcohol to the corresponding carboxylic acids in aqueous reaction media.3. A serious graphited carbon (GC) at different temperature by a functional ionic liquid [Si-mim][Cl], characterized the structure and morphology. Furthermore, a serious GC-Pt nanoparticle hybrids were prepared, and the catalytic performances of GC-Pt nanoparticle hybrids were evaluated for the electrocatalytic oxidation of methanol. The results are as follows: the GC-Pt-700 nanoparticle hybrids show the best electrocatalytic activity (400 mAmg-1).