Synthesis of Equimolar Pd-Ru Alloy Nanoparticles Incorporated Mesoporous Alumina Films: A High Performance Reusable Film Catalyst

We report the synthesis of equimolar Pd-Ru alloy nanoparticles (NPs) incorporated mesoporous alumina films (Pd-Ru/MAF) by the sol-gel route. The synthetic strategy involves homogeneous mixing of the Pd2+ and Ru3+ ions in the alumina sol containing P123 micelles. Dip-coated films, prepared on ordinary glass substrates, were thermally reduced at a relatively lower temperature (500 degrees C) to generate equimolar Pd-Ru/MAF with a nominal molar composition of Pd:Ru:AlO1.5=2:2:96. Electron microscopy studies revealed uniformly distributed Pd-Ru alloy NPs in a mesoporous alumina-alumina sphere composite film matrix. The P123/alumina nanocomposite acted as an excellent breeding medium to form Pd-Ru (similar to 1:1) alloy NPs despite the poor miscibility of the two metals. Pd-Ru/MAF showed excellent catalytic performances with highest normalized rate constant values (5.43 X 10(14) min(-1) mol(-2)) and possessed good reusability compared to the corresponding monometallic analogues in the reduction of aqueous 4-nitrophenol in the presence of NaBH4 at 25 degrees C.