Off-campus UNL users: To download campus access dissertations, please use the following link to log into our proxy server with your NU ID and password. When you are done browsing please remember to return to this page and log out.
Non-UNL users: Please talk to your librarian about requesting this dissertation through interlibrary loan.
Analytical application of surface-enhanced Raman scattering in the study of solid-solution interfaces
Abstract
Surface enhanced Raman scattering (SERS) or Surface enhanced resonance Raman scattering (SERRS) has been combined with other conventional analytical methods, as a new emerging analytical technique, to characterize and quantitate the solid-solution interfacial species. In chapter 2, a simple, highly reproducible chemical procedure for preparing SERS-active Ag substrate is demonstrated. Conventional Tollen's reagent was used to coat Ag onto frosted glass slides. Optimization of the experimental parameters (AgNO$\sb3$ concentration, solution temperature and deposition time) was achieved by using 4,4$\sp\prime$-bipyridine (bipy) as the analyte. Five orders of enhancement factor and 1 $\times$ 10$\sp{-7}$ M detection limit were achieved for bipy, with a good linearity in the concentration vs. SERS intensity plots over 3 orders of magnitude. In chapter 3, the potential application of SERRS as an ancillary HPLC detector for four nitrophenols has been assessed. Each nitrophenolate shows its own distinct Resonance Raman (RR) and SERRS spectrum, but the detection limit of the later is 2-3 orders of magnitude lower than that of RR. In chapter 4, the electrochemical and spectroscopic behavior of the phenoxazine-type mediator Nile Blue A adsorbed on glass carbon (GC) and Ag electrode was studied. The pH dependence of the formal redox potential and catalytic oxidation of NADH was similar, though not exactly the same, on both types of electrodes. Changes in the surface Raman spectra as a function of pH are interpreted to reflect orientational changes of Nile Blue A at the electrode surface. Nile Blue A and a complex formed between Nile Blue A and NADH can be distinguished by SERRS. In chapter 5, RR and SERRS were used to study the behavior of 2-(4$\sp\prime$-hydroxyphenylazo)benzoic acid (HABA) at different pH values (2.7-11.8) in solution and bound to avidin. The Raman spectra explicity reveal the deprotonation of the phenolic and carboxylic acid functional group of HABA and the equilibrium of its tautomeric forms. The Raman spectra also indicate the HABA-avidin complex is not dissociated on the Ag surface.
Subject Area
Chemistry
Recommended Citation
Ni, Fan, "Analytical application of surface-enhanced Raman scattering in the study of solid-solution interfaces" (1989). ETD collection for University of Nebraska-Lincoln. AAI9004697.
https://digitalcommons.unl.edu/dissertations/AAI9004697