Scientific Reports ( IF 3.8 ) Pub Date : 2019-04-17 , DOI: 10.1038/s41598-019-42566-3 Ievgen I. Nedrygailov , Song Yi Moon , Jeong Young Park
Hot electrons generated on metal catalysts influence atomic and molecular processes, leading to hot electron-driven catalytic reactions. Here, we show the acceleration of electrocatalytic hydrogen evolution caused by internal injection of hot electrons on Pt/Si metal–semiconductor electrodes. When a forward bias voltage is applied to the Pt/Si contact, hot electrons are injected. The excess energy of these electrons allows them to reach the Pt/electrolyte interface and reduce the adsorbed hydrogen ions to form H2 (2H+ + 2e−→H2). We show that the onset potential of the hydrogen evolution reaction shifts positively by 160 mV while the cathodic current exhibits an 8-fold increase in the presence of hot electrons. The effect disappears when the thickness of the Pt film exceeds the mean free path of the hot electrons. The concept of a hot electron-driven reaction can lead to the development of a novel mechanism for controlling reactivity at liquid–solid interfaces.
中文翻译:
金属-半导体纳米二极管电极上的热电子驱动的电催化氢析出反应
金属催化剂上产生的热电子会影响原子和分子过程,从而导致热电子驱动的催化反应。在这里,我们显示了由热电子在Pt / Si金属-半导体电极上的内部注入引起的电催化氢释放的加速。当向Pt / Si触点施加正向偏置电压时,会注入热电子。这些电子的过剩能量允许它们到达的Pt /电解质界面,降低了吸附的氢离子以形成ħ 2(2H + + 2e中- →H 2)。我们表明,氢气放出反应的起始电位正向移动了160 mV,而阴极电流在存在热电子的情况下展现了8倍的增加。当Pt膜的厚度超过热电子的平均自由程时,该效应消失。热电子驱动反应的概念可以导致控制液体-固体界面反应性的新机制的发展。