Influence of ligand structure on the stability and oxidation of copper nanoparticles.

TLDR: Alkanethiols and oleic acid were found to improve air stability and oxidation resistance of thiol-capped copper nanoparticles was found to increase with the chain length of the thiol, however, excess thiol caused etching of the particles under nitrogen.

About: This article is published in Journal of Colloid and Interface Science.The article was published on 2008-02-01 and is currently open access. It has received 259 citations till now. The article focuses on the topics: Copper & Oleic acid.

Figures

Fig. 1. UV–vis spectra of lauric acid-capped copper nanoparticle colloids at different times after exposure to air. The particles were aged for 3 days in toluene solution under nitrogen.

Table 1. The position of Cu(0) surface plasmon in UV-vis spectrum after ligand-exchange. Immediately after the synthesis the plasmon has absorbance of 0.738 A.U. and it is located at 557 nm.

Fig. 5. Surface plasmon absorbance of ligand-exchanged Cu(0) nanoparticles with different ligands and excesses. The absorbance is presented relative to the absorbance at the beginning of oxidation. Absorbance reading has been taken at the peak of plasmon absorbance at any time and not at a fixed wavelength. (A) C6SH, (B) C12SH, (C) C18SH, (D) oleic acid. (●) Lauric acidcapped nanoparticles, (■) ligand/metal ratio 1/1, (▴) 10/1, (♦) 20/1.

Fig. 2. TEM image of lauric acid-capped copper nanoparticles. The particle size was 3.3±0.7 nm.

Fig. 4. Evolution of UV–vis spectra of ligand-exchanged copper nanoparticles after air exposure. (A) C18SH (ligand/metal ratio 1/1), (B) C18SH (20/1), (C) oleic acid (1/1), (D) oleic acid (20/1).

Fig. 3. XRD spectrum of oxidized lauric acid-capped copper nanoparticles.