Synthesis of mixed metallic nanoparticles by spark discharge

• Published in: Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology 2009-07, Vol.11 (5), p.1209-1218
• Main Authors: Tabrizi, N. S., Xu, Q., van der Pers, N. M., Lafont, U., Schmidt-Ott, A.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Electrodes; Inorganic Chemistry; Lasers; Materials Science; Nanoparticles; Nanotechnology; Optical Devices; Optics; Photonics; Physical Chemistry; Technology and Applications; X-ray diffraction; X-ray spectroscopy; X-rays
• ISSN: 1388-0764; 1572-896X
• DOI: 10.1007/s11051-008-9568-8

Short spark discharges (2 μs) were successfully applied to generate mixed particles a few nanometres in diameter by fast quenching. Alloyed Cr–Co electrodes were applied to demonstrate this. Further it was shown that if the anode and the cathode are different materials, the discharge process mixes the vapour of both materials, forming mixed nanoparticles. Electron microscopy (TEM, SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) analyses were performed on the collected particles to study their size, morphology, composition and structure. The average compositions of the particles were measured by inductively coupled plasma (ICP). In addition, online measurements of the particle size distribution by mobility analysis were carried out. In the case of alloyed electrodes (Cr–Co), the relative concentration of the elements in the nanoparticulate sample was consistent with the electrode composition. When using electrodes of different metals (Au–Pd and Ag–Pd) the individual nanoparticles showed a range of mixing ratios. No surface segregation was observed in these mixed noble metal particles. Crystalline nanoparticulate mixed phases were found in all cases.