TY - JOUR
T1 - Near-Infrared Optical Response and Carrier Dynamics for High Photoconversion in Tellurene
AU - Villegas, Cesar E.P.
AU - Rocha, Alexandre R.
N1 - Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
PY - 2022/4/14
Y1 - 2022/4/14
N2 - Materials for applications in solar cells require a combination of features including an appropriate band gap and long relaxation times for photoexcited hot carriers. On the basis of ab initio many-body perturbation theory, including the spin-orbit interaction, we investigate the photocarrier generation and dynamics in α-tellurene. We show that photoexcited electrons are mainly generated in the near-infrared range, starting at 0.89 eV and forming excitons that are strongly bound, compared to its bulk counterpart, with a binding energy of 0.31 eV. We also explore the role of the electron-phonon interaction, finding that the electronic states in the first conduction band minimum couples weakly with phonons, yielding longer hot electron lifetimes (up to 70 fs) and mean free paths up to 37 nm. We also show that the extraction of hot holes may result in a challenging task as these carriers possess sub-3 nm mean free paths. We finally estimate that 1-nm-thick α-Te provides a short-circuit current density of 6.7 mA/cm2and a maximum power conversion efficiency of 4.4%, which highlights its potential for efficient photovoltaic device development.
AB - Materials for applications in solar cells require a combination of features including an appropriate band gap and long relaxation times for photoexcited hot carriers. On the basis of ab initio many-body perturbation theory, including the spin-orbit interaction, we investigate the photocarrier generation and dynamics in α-tellurene. We show that photoexcited electrons are mainly generated in the near-infrared range, starting at 0.89 eV and forming excitons that are strongly bound, compared to its bulk counterpart, with a binding energy of 0.31 eV. We also explore the role of the electron-phonon interaction, finding that the electronic states in the first conduction band minimum couples weakly with phonons, yielding longer hot electron lifetimes (up to 70 fs) and mean free paths up to 37 nm. We also show that the extraction of hot holes may result in a challenging task as these carriers possess sub-3 nm mean free paths. We finally estimate that 1-nm-thick α-Te provides a short-circuit current density of 6.7 mA/cm2and a maximum power conversion efficiency of 4.4%, which highlights its potential for efficient photovoltaic device development.
UR - http://www.scopus.com/inward/record.url?scp=85128517605&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.1c10526
DO - 10.1021/acs.jpcc.1c10526
M3 - Artículo
AN - SCOPUS:85128517605
SN - 1932-7447
VL - 126
SP - 6129
EP - 6134
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 14
ER -