Eur. Phys. J. B 41, 43-48 (2004)
https://doi.org/10.1140/epjb/e2004-00291-9

On-line monitoring of Au nanoparticles formation by optical spectroscopy

¹ Istituto per I Materiali Compositi e Biomedici – Consiglio Nazionale delle Ricerche, Piazzale Tecchio 80, 80125 Naples, Italy
² Istituto di Cibernetica – Consiglio Nazionale delle Ricerche “ E Caianiello”, Via Campi Flegrei 34, 80078-Pozzuoli, Italy
³ Coherentia INFM – Università di Napoli “Federico II” – Dipartimento Scienze Fisiche, Fac. Ingegneria, P.le Tecchio 80, 80125 Napoli, Italy

Corresponding author: ^a gpepe@na.infn.it

Received: 7 April 2004
Revised: 13 July 2004
Published online: 30 September 2004

Abstract

Experimental results concerning the synthesis of gold nanoparticles prepared by alcoholic reduction of Au(III) ions in presence of a polymeric stabilizer, and UV-visible spectroscopic characterization is presented. Optical spectroscopic data have been correlated to off-line size measurements obtained analysing transmission electron micrographs. The gold cluster size, coming from both TEM micrographs and absorbance cubic root, behaved linearly with time above a threshold temperature (70 °C) according to a deposition-controlled growth mechanism. The plasmon peak halfwidth behaved linearly with inverse particle radius (obtained by TEM), thus proving the hypothesized mechanism growth. The spectroscopic approach allows an on-line gold cluster measurement with possibility to fine control particle size also in the case of a fast process.