Fe3O4@Carbon Microsphere Supported Ag–Au Bimetallic Nanocrystals with the Enhanced Catalytic Activity and Selectivity for the Reduction of Nitroaromatic Compounds

摘要: The heterostructure Ag–Au bimetallic nanocrystals supported on Fe3O4@carbon composite microspheres were synthesized by one facile and controllable approach, wherein the Ag attached prepared first served as reductant for galvanic replacement reaction with Au precursor (HAuCl4). Upon varying feeding amounts of precursor, compositions microsphere could be readily tuned resulting in a series different Au-to-Ag molar ratios. Subsequently, we thus investigated catalytic activity selectivity magnetic catalysts from two sides. First, 4-nitrophenol (4-NP) was applied model molecule to study effect ratios capabilities microspheres. It found that upon addition NaBH4 capability markedly enhanced when content increased. maximum ...