We studied the chemical changes undergone by gallic acid (GA) when adsorbed on a colloidal silver surface by means of surface-enhanced Raman spectroscopy (SERS). The application of the SERS technique allows a remarkable Raman sensitivity enhancement and the strong fluorescence quenching needed to characterize the highly colored products of GA oxidative condensation. We found that GA can undergo a ring opening, a polymerization of aromatic rings or a combination of both mechanisms, leading to the formation of humic-like substances. The influence of pH and light irradiation on these catalytic processes was investigated in relation to the importance of these mechanisms. © 2001 John Wiley & Sons, Ltd.
Catalytic modification of gallic acid on a silver surface studied by surface-enhanced Raman spectroscopy / Alvarez-Ros M.C.; Sanchez-Cortes S.; Francioso O.; Garcia-Ramos J.V.. - In: JOURNAL OF RAMAN SPECTROSCOPY. - ISSN 0377-0486. - STAMPA. - 32:2(2001), pp. 143-145. [10.1002/jrs.683]
Catalytic modification of gallic acid on a silver surface studied by surface-enhanced Raman spectroscopy
Francioso O.;
2001
Abstract
We studied the chemical changes undergone by gallic acid (GA) when adsorbed on a colloidal silver surface by means of surface-enhanced Raman spectroscopy (SERS). The application of the SERS technique allows a remarkable Raman sensitivity enhancement and the strong fluorescence quenching needed to characterize the highly colored products of GA oxidative condensation. We found that GA can undergo a ring opening, a polymerization of aromatic rings or a combination of both mechanisms, leading to the formation of humic-like substances. The influence of pH and light irradiation on these catalytic processes was investigated in relation to the importance of these mechanisms. © 2001 John Wiley & Sons, Ltd.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
