Underpotential deposition of lead on quasi-spherical and faceted gold nanoparticles

• Published in: Journal of electroanalytical chemistry (Lausanne, Switzerland) Switzerland), 2018-06, Vol.819, p.159-162
• Main Authors: Jeyabharathi, C., Zander, M., Scholz, F.
• Format: Article
• Language: English
• Subjects: Crystal structure; Crystallinity; Gold; Lead; Nanoparticles; Roughening; Silver chloride; Stripping; Underpotential deposition
• ISSN: 1572-6657; 1873-2569
• DOI: 10.1016/j.jelechem.2017.10.011

The underpotential deposition of lead was studied on spherical and faceted gold nanoparticles. On 21.7nm spherical nanoparticles, a single stripping peak from Au(111) face was observed at −0.2V, whereas on 82nm faceted gold nanoparticles the peak split in to two at −0.2V and −0.18V vs Ag/AgCl (3M KCl). The roughening of the Au(111) terraces by electrochemical treatment leads to the suppression of the spike. It appears that the extent of surface crystallinity of nanoparticles causes the observed differences in the upd-stripping behaviour. The splitting of the Pb-upd stripping peak from Au(111) face can be used as an indication for the surface crystallinity of gold nanoparticles. •Quasi-spherical AuNPs show a single upd-Pb stripping peak at −0.2V for (111) face.•On faceted AuNPs the upd-Pb peak at −0.2V splits into two with a spike at −0.18V like a single crystalline (111) face.•Suppression of the spike at −0.2V upon cleaning cycles of faceted AuNPs is due to the roughening of the (111) terraces.•The spike at −0.18V on faceted AuNPs is a result of kinetic effects, and is affected by the size of the (111) terraces.•The appearance of the spike at −0.18V can be used as an indicator of the surface crystallinity of gold nanoparticles.