Al-X and Cu-X [X = Li, Na] nano-alloys: a low cost alternative to silver and gold nanoparticles for plasmonic applications

• Published in: RSC advances 2015-01, Vol.5 (72), p.58128-58135
• Main Authors: Debnath, Shaikat, Said, Suhana Mohd, Rabilloud, Franck, Chatterjee, Abhijit, Rashid, Mohammad Mamunur, Mainal, Azizah
• Format: Article
• Language: English
• Subjects: Aluminum; Chemical Sciences; Clusters; Copper; Electronics; Engineering Sciences; Gold; Lithium; Optical properties; Physics; Silver
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c5ra10135b

We present a systematic study of the electronic and optical properties of the Li and Na doped Al-X and Cu-X (X = Li, Na) nanoalloys in the framework of density functional theory in order to evaluate their potential as low cost plasmonic materials as alternatives to silver and gold. A single atom in the 13 atoms Al and Cu clusters is replaced by the Li and Na atoms in the core and surface positions to form core-doped and surface-doped Al 12 X and Cu 12 X bimetallic clusters respectively. Vibrational analysis has ensured the structural stability of the doped clusters. Binding energies and HOMO-LUMO gaps are calculated to predict the electronic stability, as well as the ionization potential and electron affinity of the clusters. Large HOMO-LUMO gaps with small electron affinity of the doped clusters ensured that anions of the Cu 12 X and Al 12 X clusters will be very reactive. The optical absorption properties of the undoped and doped clusters are calculated in the framework of TDDFT. It is observed that the Li and Na doping into the Al and Cu clusters yield significant increase in the absorption band-gap in both of the Cu and Al clusters. In particular, the surface doped Al 12 X clusters exhibit remarkable large bandgap which comprises from 3 eV to 11 eV. Due to their electronic and optical properties, the Al-X and Cu-X doped clusters may be considered as an excellent low cost alternative to silver and gold, which can find its worth in catalytic, opto-electronic and UV-absorption applications. Single X atom (X = Li and Na) is doped into Cu and Al to form Cu 12 X and Al 12 X clusters. The Al 12 X clusters exhibit remarkable optical absorption properties in the range of 3-11 eV.