Year: 2025
Type: article
Abstract: Hot carrier solar cells (HCSCs), harvesting the excess energy of hot carriers generated by above-band gap photoexcitation, are crucial for pushing the solar cell efficiency beyond the Shockley–Queisser limit, which is challenging to realize mainly due to fast hot-carrier cooling. By performing transient reflectance spectroscopy in a MoSe 2 /hBN/WS 2 junction, we demonstrate the gate-tunable harvest of hot electrons from MoSe 2 to WS 2 . By spectrally distinguishing hot-electron extraction from lattice temperature increase, we find that electrostatically doped electrons in MoSe 2 can boost hot-electron extraction density ( n ET ) by a factor up to several tens. Such enhancement arises from the interaction between hot excitons and doped electrons, which converts the excess energy of hot excitons to excitations of the Fermi sea and hence generates hot electrons. Moreover, n ET can be further enhanced by reducing the conduction band offset with an external electric field. Our results provide in-depth insights into the design of HCSCs with electrostatic strategies.
Source: Nano Letters
Authors: Chenran Xu, Chen Xu, Jichen Zhou, Zhexu Shan, Wenjian Su, Wenbing Li, Xingqi Xu, Kenji Watanabe, Takashi Taniguchi, Shiyao Zhu, Dawei Wang, Yanhao Tang
Institutions: Zhejiang University, National Institute for Materials Science
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Funders: Ministry of Education, Culture, Sports, Science and Technology, National Natural Science Foundation of China, Zhejiang University, Shanghai Jiao Tong University, Japan Society for the Promotion of Science, National Key Research and Development Program of China, Natural Science Foundation of Zhejiang Province
OpenAlex ID: W4409627346