Resonance Raman and surface- and tip-enhanced Raman spectroscopy methods to study solid catalysts and heterogeneous catalytic reactions

Abstract

Resonance Raman (RR) spectroscopy has several advantages over the normal Raman spectroscopy (RS) widely used for in situ characterization of solid catalysts and catalytic reactions. Compared with RS, RR can provide much higher sensitivity and selectivity in detecting catalytically-significant surface metal oxides. RR can potentially give useful information on the nature of excited states relevant to photocatalysis and on the anharmonic potential of the ground state. In this critical review a detailed discussion is presented on several types of RR experimental systems, three distinct sources of so-called Raman (fluorescence) background, detection limits for RR compared to other techniques (EXAFS, PM-IRAS, SFG), and three well-known methods to assign UV-vis absorption bands and a band-specific unified method that is derived mainly from RR results. In addition, the virtues and challenges of surface-enhanced Raman spectroscopy (SERS) are discussed for detecting molecular adsorbates at catalytically relevant interfaces. Tip-enhanced Raman spectroscopy (TERS), which is a combination of SERS and near-field scanning probe microscopy and has the capability of probing molecular adsorbates at specific catalytic sites with an enormous surface sensitivity and nanometre spatial resolution, is also reviewed (300 references).

Quantitative Determination of Iron Ions Based on a Resonance Raman (RR) Probe-Phenanthroline

“…14,17,18 This method has also been implemented in a number of analyses, such as analytical testing, surface science, and biomedical research, in different regions. 19 Phenanthroline is typically employed as a chromogenic agent in colorimetric and spectrophotometric assays of Fe 3+ /Fe 2+ ions because water-soluble metal complexes form between the ions and agent [20][21][22][23] …”

Advances in surface-enhanced vibrational spectroscopy at electrochemical interfaces

“…A significant issue that has precluded widespread uptake of TERS relates to the reliable fabrication and availability of suitable probes [118,121], although recent advances have improved the measurement and understanding of enhancement factors [122,123] as well as probe degradation mechanisms [124]. Despite these challenges, the potential of TERS for studying surface reactions in situ is well-recognised and advances have been demonstrated in a number of cases [125][126][127][128][129].…”

Investigation of the Kinetics of a Surface Photocatalytic Reaction in Two Dimensions with Surface‐enhanced Raman Scattering

“…Surface‐enhanced Raman spectroscopy (SERS) is gaining increasing popularity in this field as a powerful characterization tool 3. Typically, silver or gold nanostructured surfaces are used to enhance Raman spectra of molecules, with a sensitivity that reaches single‐molecule levels 4.…”