講演情報
[23a-13N-7]Vibrational excitation of carbon dioxide on gold nanoslits by plasmonically enhanced mid-infrared pulses
〇(M2)Qiuming Wan1, Ikki Morichika1, Naoki Ichiji1, Satoshi Ashihara1 (1.IIS, The Univ. of Tokyo)
キーワード：
Pump-probe spectroscopy、Vibrational excitation、Surface plasmon resonance
It is known that selective cleavage and generation of chemical bonds can be achieved through intense vibrational excitation induced by infrared femtosecond pulses. One of the challenging applications of such vibrational control is for metal-surface reactions. Recently, several studies have theoretically suggested that vibrational excitation of CO2 can play an important role in the metal-catalyzed CO2conversion. In this study, we report on vibrational excitation of anti-symmetric stretch of CO2 by plasmonically enhanced mid-infrared pulses.
We perform reflection pump-probe spectroscopy for the sample, Au nanoslits with 24times field enhancement which are covered with 25 μm of CO2-saturated EMIM-BF4 solutions. The negative reflectance change due to ground state bleach and stimulated emission and the positive reflectance change due to excited state absorption are observed after pump excitation. From the ratio of the linear and transient reflectance changes, it is estimated that approximately 50% of the molecules are excited.
We perform reflection pump-probe spectroscopy for the sample, Au nanoslits with 24times field enhancement which are covered with 25 μm of CO2-saturated EMIM-BF4 solutions. The negative reflectance change due to ground state bleach and stimulated emission and the positive reflectance change due to excited state absorption are observed after pump excitation. From the ratio of the linear and transient reflectance changes, it is estimated that approximately 50% of the molecules are excited.