Premium
Charge Photogeneration in Few‐Layer MoS 2
Author(s) -
Borzda Tetiana,
Gadermaier Christoph,
Vujicic Natasa,
Topolovsek Peter,
Borovsak Milos,
Mertelj Tomaz,
Viola Daniele,
Manzoni Cristian,
Pogna Eva A. A.,
Brida Daniele,
Antognazza Maria Rosa,
Scotognella Francesco,
Lanzani Guglielmo,
Cerullo Giulio,
Mihailovic Dragan
Publication year - 2015
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.201500709
Subject(s) - photoexcitation , materials science , photodetector , exciton , optoelectronics , active layer , semiconductor , charge carrier , layer (electronics) , photovoltaic system , photovoltaic effect , spectroscopy , nanotechnology , atomic physics , physics , excited state , condensed matter physics , ecology , quantum mechanics , biology , thin film transistor
The 2D semiconductor MoS 2 in its mono‐ and few‐layer form is expected to have a significant exciton binding energy of several 100 meV, suggesting excitons as the primary photoexcited species. Nevertheless, even single layers show a strong photovoltaic effect and work as the active material in high sensitivity photodetectors, thus indicating efficient charge carrier photogeneration. Here, modulation spectroscopy in the sub‐ps and ms time scales is used to study the photoexcitation dynamics in few‐layer MoS 2 . The results suggest that the primary photoexcitations are excitons that efficiently dissociate into charges with a characteristic time of 700 fs. Based on these findings, simple suggestions for the design of efficient MoS 2 photovoltaic and photodetector devices are made.