Fabrication of novel electronic-catalysts by using MIM tunnel junction

金属表面电子态的精确和可调控制应该与新型催化反应直接相关。金属-绝缘体-金属（MIM）隧道结在偏压作用下产生单色热电子，是一种很好的热电子产生器件。本研究的目的是阐明隧道结表面作为吸附分子的表面反应的促进剂。利用表面增强拉曼散射（Sers）技术研究了对硝基苯甲酸（PNBA）和邻硝基苯甲酸（ONBA）在Ag（Au）/AlOx/Al隧道结的Ag（Au）顶电极上的热电子诱导表面反应.结果表明，在正偏压下产生的热电子通过表面等离子体激元共振（SPP）诱导吸附分子在电极顶面发生还原偶联反应生成偶氮二苯甲酸盐.

Precise and tunable control in electronic states of the metal surface should be directly linked to a novel catalytic reaction. Metal-insulator-metal (MIM)tunnel junction, which generates monochromatic hot-electrons under bias-voltage, would be one of the suitable devices for the hot-electron generation. The aim of this study is to clarify the tunnel junction surface works as a promoter of the surface reaction of the adsorbed molecules. We investigate the hot-electron-induced surface reaction of p-and o-nitrobenzoic acid (PNBA, ONBA)on the Ag(Au)top electrode of the Ag(Au)/AlOx/Al tunnel junction by using surface enhanced Raman scattering (SERS). The results show that the hot-electron generated under positive-bias voltage can induce reductive coupling reaction of the adsorbed molecules to generate azodibenzoate at the top electrode surface through surface plasmon polariton (SPP)resonance.