Enhanced photochemistry on silver surfaces
Enhanced photochemistry on silver surfaces
复制标题
增强银表面的光化学作用
DOI：
10.1063/1.453508
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发表时间：
1987
影响因子：
4.4
通讯作者：
M. Moskovits
中科院分区：
文献类型：
--
作者：
R. Wolkow;M. Moskovits
研究发现，吡嗪和三嗪在粗糙的银表面上发生光碎裂，形成主要产物石墨炭。速率决定步骤被发现是双光子的。由于激发分子的非辐射驰豫和表面增强电场的激发之间的竞争，增强的光化学作用最有效地直接发生在金属表面，而不是在表面上方的短距离处。此外，还发现有可能通过在吸附的分子上覆盖适当数量的光试剂本身或另一分子的层来进一步提高光解速率，从而将粗糙表面的局域表面等离子激元调节为与激发激光共振。我们建议在先前的报告中[Goncher，Parsons，and Harris，J.Phys.化学。[88,4200(1984)]用间隔层将光试剂从粗糙表面置换出来的效果是显著的。
Pyrazine and triazine are found to photofragment on rough silver surfaces to form graphitic carbon as a major product. The rate‐determining step is found to be biphotonic. The enhanced photochemistry is shown to take place most efficiently directly at the metal surface rather than a short distance above the surface as would be expected on the basis of a competition between nonradiative relaxation of the excited molecule and excitation by the surface‐enhanced electric field. Moreover, it was found possible to increase the photolysis rate further by overcoating the adsorbed molecules with an appropriate number of layers either of the photoreagent itself or of another molecule, tuning thereby the localized surface plasmon of the rough surface into resonance with the exciting laser. We suggest that in a previous report [Goncher, Parsons, and Harris, J. Phys. Chem. 88, 4200 (1984)] of enhanced photochemistry at rough surfaces the effect of displacing the photoreagent from the surface using spacer layers was in...