Surface-enhanced Raman scattering of p-nitrobenzoic acid on Ag-coated Au nanoparticle surfaces

CHED 1038

Rachel K. Kaneta, rkaneta@linfield.edu, Evan A. Hiles, ehiles@linfield.edu, and Brian D. Gilbert. Department of Chemistry, Linfield College, 190 SW Brumback St., Unit 3321, McMinnville, OR 97128
Photoreaction kinetics of p-nitrobenzoic acid (PNBA) on Ag-coated Au nanoparticle slides were studied using surface-enhanced Raman scattering (SERS). PNBA was adsorbed to the slides by soaking the slides in 0.1 M PNBA. The photoreduction of PNBA to form azodibenzoic acid (ADBA) on the prepared surfaces was observed in real time with SERS spectra (532 nm excitation) under ambient conditions. Spectral features consistent with ADBA were clearly observed, with the most significant growth within the first 10 min of irradiation. The intensity of a characteristic photorproduct band was monitored in order to measure photoreaction progress. An exponential kinetic curve was fit to the data and the rate constant was determined to be 0.13 ± 0.01 s-1.