Ultrafast Plasmonic Hot Electron Transfer in Au Nanoantenna/MoS₂ Heterostructures

详细信息    查看全文

• 作者：Ying Yu ; Ziheng Ji ; Shuai Zu ; Bowen Du ; Yimin Kang ; Ziwei Li ; Zhangkai Zhou ; Kebin Shi and Zheyu Fang
• 刊名：Advanced Functional Materials
• 出版年：2016
• 出版时间：September 20, 2016
• 年：2016
• 卷：26
• 期：35
• 页码：6394-6401
• 全文大小：2703K
• ISSN：1616-3028

文摘

2D transition metal dichalcogenides are becoming attractive materials for novel photoelectric and photovoltaic applications due to their excellent optoelectric properties and accessible optical bandgap in the near-infrared to visible range. Devices utilizing 2D materials integrated with metal nanostructures have recently emerged as efficient schemes for hot electron-based photodetection. Metal-semiconductor heterostructures with low cost, simple procedure, and fast response time are crucial for the practical applications of optoelectric devices. In this paper, template-based sputtering method is used first to fabricate Au nanoantenna (NA)/MoS₂ heterostructures with low cost, simple preparation, broad spectral response, and fast response time. Through the measurement of femtosecond pump-probe spectroscopy, it is demonstrated that plasmon-induced hot electron transfer takes place in the Au NA/MoS₂ heterostructure on the order of 200 fs with an injected electron density of about 5.6 × 10¹² cm⁻². Moreover, the pump-power-dependent photoluminescence spectra confirm that the exciton energy of MoS₂ can be enhanced, coupled, and reradiated by the Au NA. Such ultrafast plasmon-induced hot electron transfer in the metal-semiconductor heterostructure can enable novel 2D devices for light harvesting and photoelectric conversion.