Study On The Synthesis Of Nobel Metal Nanoparticles Using Glow Discharge Plasma Reduction

Nobel metal nanoparticles have drawn great attention because of their unique optical, electronic, magnetic properties for catalytic, electronic, biomedical and aerospace applications. Glow discharge plasma, as one of the cold plasma, has the characteristics of high electron energy and low gas temperature. Glow discharge plasma reduction is an effective and green reduction method. Comparing with conventional chemical reduction, plasma reductions don't need any stabilizinf or reducing agent, according with therequirement of green chemistry.We use the step-by-step precipitation method to prepare AuPd bimetallic nanoparticles on the anodic aluminum oxide(AAO) surface using room-temperature electron reduction with argon glow discharge as electron source. Characterition of the AuPd-AAO, Au-AAO, Pd-AAO was performed using the XRD, XPS, TEM and UV-vis. The analysis shows that Au4+ and Pd2+ could be reduced to Au(0) and Pd(0) by glow discharge plasma at room-temperature; The sample AuPd-AAO is consisted of three kinds of nanoparticles, Au nanopartilces, Pd nanoparticles and AuPd alloyed nanoparticles; AuPd alloyed nanoparticles are spherical and the average size of the particles is 14 nm. Then, we prepared AuPd-AAO samples with different Au/Pd molar ratios using argon glow discharge as electron source. The analysis shows Pd-AAO samples with different Au/Pd molar ratios are also consisted of AuPd alloyed nanoparticles and the size of the alloyed AuPd nanoparticles reduces with the increasing Pd content. These results show alloyed AuPd nanoparticles can be prepared by glow discharge plasma.We treated H2PtCl6 and NaCl mechanical mixture glow discharge plasma and H2 redution, and got sample Pt-NaCl-P and Pt-NaCl-H. Characterition of the Pt-NaCl was conducted using the XRD?TEM?CO-DRIFT. The analysis shows, Pt4+ can be reduced to Pt nanoparticles by either plasma or H2 redution; for the sample Pt-NaCl-H,Pt nanoparticles were irregular shape and the average size of the particles is 22.3 nm;for the sample Pt-NaCl-P,Pt nanoparticles are spherical, the average size of the particles is 22.3 nm. The sample Pt-NaCl-P was dissolved in CH3 OH solution and ultrasonically dispersed for 30 min. Pt nanoparticles can be separated from NaCl. Then, we use the same approach to treat HAuCl4 and NaCl mixture.We can get Au nanoparticles with the average size is 22.29 nm.