| Title | Electron transfer and cascade relaxation dynamics of graphene quantum dots/MoS2 monolayer mixed-dimensional van der Waals heterostructures |
| Authors | Shan, Hangyong Yu, Ying Zhang, Rui Cheng, Runtan Zhang, Dong Luo, Yang Wang, Xingli Li, Bowen Zu, Shuai Lin, Feng Liu, Zheng Chang, Kai Fang, Zheyu |
| Affiliation | Peking Univ, Acad Adv Interdisciplinary Studies, Collaborat Innovat Ctr Quantum Matter, State Key Lab Mesoscop Phys,Sch Phys, Beijing 100871, Peoples R China Chinese Acad Sci, Inst Semicond, SKLSM, Beijing 100083, Peoples R China Shanghai Jiao Tong Univ, Sch Life Sci & Biotechnol, Shanghai 200240, Peoples R China Nanyang Technol Univ, CINTRA, Singapore 637553, Singapore |
| Issue Date | 2019 |
| Publisher | MATERIALS TODAY |
| Abstract | Van der Waals (VdW) heterostructures have emerged as promising materials for atomically thin optoelectronic and photovoltaic applications, where the efficient charge separation after photoexcitation is significant to enhance device performances. However, modulating the interfacial charge transfer is still challenging due to the weak interlayer VdW interaction. Revealing electron transfer and relaxation processes in heterostructures lays foundation to tune the interfacial dynamics and optoelectronic properties. Here, we realize the efficient modulation of relaxation channels in MoS2 monolayers and interfacial electron transfer by forming mixed-dimensional VdW heterostructures with graphene quantum dots (GQDs). With femtosecond pump-probe spectroscopy, the biphasic electron injection model and modified rate equations are employed to quantitatively solve interfacial transfer rates of mixed-dimensional VdW heterostructures. We find that the cascaded relaxation of hot electrons in GQDs that originates from the quantum confinement effect can intensively affect the interfacial dynamics. Our established model is instructive to optimize performances of future photon-harvesting devices based on mixed low-dimensional heterostructures. |
| URI | http://hdl.handle.net/20.500.11897/549547 |
| ISSN | 1369-7021 |
| DOI | 10.1016/j.mattod.2019.01.015 |
| Indexed | SCI(E) EI |
| Appears in Collections: | 前沿交叉学科研究院 人工微结构和介观物理国家重点实验室 |
