| AVS 60th International Symposium and Exhibition | |
| Plasma Science and Technology | Thursday Sessions |
| Session PS+AS+NS+SS-ThM |
| Session: | Plasma Synthesis of Nanostructures |
| Presenter: | M.A. Bratescu, Nagoya University, Japan |
| Authors: | M.A. Bratescu, Nagoya University, Japan N. Saito, Nagoya University, Japan |
| Correspondent: | Click to Email |
In our group, Solution Plasma Processing (SPP) is a useful and simple method for metal NPs (nanoparticles) synthesis [1, 2]. In the present work, we demonstrate a special merit of the SPP method for the fabrication of bimetallic NPs using a combination of the reduction reaction of the metal (M) ion to the neutral state, while simultaneously eroding the electrodes during the discharge, which generates the second metal in the structure of the bimetallic NPs [3].
The gold bimetallic NPs were synthesized by alloying gold with various types of metals, which are divided in four categories: (i) divalent sp metals, Zn and Cd, (ii) trivalent sp metals, Ga and In, (iii) 3d metals Fe, Co, Ni, and Cu, and (iv) 4d metals Pd and Ag. We used SPP between two gold electrodes immersed in a nitrate solution of the corresponding metal M. We studied the optical properties of the gold nanoalloys, as well as their crystallinity, composition, size and morphology, and we have evaluated the interaction of various gold bimetallic NPs with free radicals for possible consideration as catalysts. SPP characterization has been done using electrical and optical probes. We found that the properties of the gold bimetallic NPs are connected with the category to which the metal belongs. We analyzed that the amount of the intermetallic compound in the composition of the gold bimetallic NPs depends on the electrochemical potential and the electron density of the Wigner-Seitz cell. The obtained gold bimetallic NPs using one step in Solution Plasma have sizes in the range from 5 to 20 nm. The difference in electronegativity between gold and the other metal was the main reason for the formation of the intermetallic compounds found in the composition of the gold bimetallic NPs. This work was supported in part by Kakenhi, Challenging Exploratory Research, JSPS, Japan.
[1] M.A. Bratescu, et al., J. Phys. Chem. C 115 (2011) 24569.
[2] S.P. Cho, et al., Nanotechnology 22 (2011) 455701.
[3] M.A. Bratescu, et al., J. Alloys and Compounds 562 (2013) 74.