PHOTOCHEMISTRY AT ADSORBATE METAL INTERFACES

Photochemistry at adsorbate/metal interfaces is a relatively new subject in the surface science community and one which provides excellent opportunities for studying adsorbate-surface interactions, including energy and charge transfer, dynamics and kinetics. In this article we review the accumulated understanding of the major issues and opportunities for developing and utilizing this kind of surface chemistry. After some brief introductory remarks on the orientation of this review and an historical perspective of photon-driven chemistry at adsorbate/metal interfaces, the fundamental concepts entering the description of photon-adsorbate-surface systems are presented. Following that, experimental evidence for various kinds of surface photochemical mechanisms is summarized. Thereafter, a detailed review of the current surface photochemistry literature is presented. While photochemistry at adsorbate/metal interfaces is the focus of this review, photochemistry at insulator and semiconductor interfaces is also described briefly to provide comparisons. In several cases, we note the limitations of our present understanding, the places where key experiments are missing and doable and, in our view, the directions and opportunities for future research.