Department of Chemistry Education, Korea National University of Education (KNUE), Chungbuk 28173, Republic of Korea.
Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Nano Lett. 2023 Jun 14;23(11):5373-5380. doi: 10.1021/acs.nanolett.3c00173. Epub 2023 Mar 17.
Excitation of hot electrons by energy dissipation under exothermic chemical reactions on metal catalyst surfaces occurs at both solid-gas and solid-liquid interfaces. Despite extensive studies, a comparative study directly comparing electronic excitation by electronically nonadiabatic interactions at solid-gas and solid-liquid interfaces has not been reported. Herein, on the basis of our techniques for monitoring energy dissipation as a chemicurrent using a Pt/n-Si nanodiode sensor, we observed the generation of hot electrons in both gas and liquid phases during HO decomposition. As a result of comparing the current signal and oxygen evolution rate in the two phases, surprisingly, the efficiency of reaction-induced excitation of hot electrons increased by ∼100 times at the solid-liquid interface compared to the solid-gas interface. The boost of hot electron excitation in the liquid phase is due to the presence of an ionic layer lowering the potential barrier at the junction for transferring hot electrons.
在金属催化剂表面的放热化学反应下，通过能量耗散激发出热电子，这种现象同时发生在固-气和固-液界面。尽管已经进行了广泛的研究，但直接比较固-气和固-液界面上通过非绝热电子相互作用进行电子激发的对比研究尚未有报道。在此，基于我们使用 Pt/n-Si 纳米二极管传感器监测作为化学电流的能量耗散的技术，我们在气相和液相中都观察到了 HO 分解过程中热电子的产生。通过比较两相中的电流信号和氧气产生速率，令人惊讶的是，与固-气界面相比，固-液界面上反应诱导的热电子激发效率提高了约 100 倍。在液相中热电子激发的增强是由于存在离子层降低了用于转移热电子的结处的势垒。
