Chapter 14 - Coupling Interfacial Electrochemistry with Nuclear Magnetic Resonance Spectroscopy: An Electronic Perspective

https://doi.org/10.1016/B978-044451870-5/50015-4Get rights and content

Publisher Summary

This chapter demonstrates the electronic investigative power of electrochemical nuclear magnetic resonance spectroscopy (EC-NMR). The chapter correlates the two most important physical attributes—the Fermi level local density of states (Ef-LDOS) and the d band center—in defining the catalytic activity of a metal surface. Using CO adsorption as a paradigm, the unique and detailed electronic/mechanistic insights on the CO–metal bonding can be obtained. They are usually complimentary to those obtained from the other spectroscopic methods. Additionally, under certain qualitative assumptions presented in the chapter, some simple correlations between the trend of variations in the Ef-LDOS and the trend of variations in the d band center can be established. The former trend can in principle be obtained by EC-NMR while the latter by quantum density functional theory (DFT) calculations or by photoemission spectroscopy of valence bands and core levels. The consistency in reasoning and predictions obtained using both attributes has been excellent so far, thus ensuring a sound physical basis for such an approach. The complementary nature of these two attributes if correlated should enable the catalytic activity of a metal surface to be better and more comprehensively defined and understood. These correlations strengthen further the ability of EC-NMR in offering a detailed electronic picture of metal–adsorbate bonding interactions by extending its base of theoretical rationales.

References (0)

Cited by (4)

  • In situ electrochemical nuclear magnetic resonance spectroscopy for electrocatalysis: Challenges and prospects

    2017, Current Opinion in Electrochemistry
    Citation Excerpt :

    In terms of unraveling molecular dynamic processes, the temperature and/or magnetic field dependence of the nuclear spin dynamics, as characterized by both the spin-lattice and spin-spin relaxation time T1 and T2 respectively, permits access to motional information over an impressive time range from ∼10−9 to 102 s. Moreover, NMR is noninvasive, applicable to almost all forms of matters (be it liquid, solid or gaseous), technically versatile for in situ measurements and imaging, and can see buried interfaces that are usually inaccessible to many other spectroscopic methods. As such, these advantageous features have continued to entice practitioners to expand its application horizon [1], including in situ measurements in the field of electrochemistry [2•–12] despite the intrinsic technical incompatibility between the conventional electrical induction detection for NMR and electrical conduction necessary for electrochemistry measurements. The initiation of in situ EC-NMR to studying Pt-based electrocatalysts and associated electrocatalysis [13–15], Figure 1a, was largely inspired by the ingenious work of Slichter and co-workers in gas–phase heterogeneous catalysis [16••,17].

View full text