New technique to observe a time evolution of a gold colloidal system in nanochannels of MCM-41 mesoporous silica using UV-Vis spectroscopy

We report a possible application of Ultra violet-visible (UV-Vis) spectroscopy technique to study a time evolution of a gold colloidal system in restricted geometry. We used a unique property of temperature and size dependence of the gold surface plasmon band. The absorption spectra show the slow and faster-nucleation of the gold atoms in the solution of HAuCl4, sodium citrate and MCM-41. The interfacial undercooling was estimated by comparing the absorption spectra of the bulk solution to the pore solution. Our result is consistent with a Gibbs-Thomson constant K = 54 ± 2 °C nm, which is in good agreement with the values given by the previous experiments [R. Schmidt, E.W. Hansen, M.D. Akporiaye, O.H. Stocker, Ellestad, J. Am. Chem. Soc. 117 (1995) 4049, A. Schreiber, I. Ketelsen, G.H. Findenegg, Phys. Chem. Chem. Phys. 3 (2001) 1185].