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Title: AID Recognizes Structured DNA for Class Switch Recombination

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1390862
Resource Type:
Journal Article
Resource Relation:
Journal Name: Molecular Cell; Journal Volume: 67; Journal Issue: 3
Country of Publication:
United States
Language:
ENGLISH

Citation Formats

Qiao, Qi, Wang, Li, Meng, Fei-Long, Hwang, Joyce K., Alt, Frederick W., and Wu, Hao. AID Recognizes Structured DNA for Class Switch Recombination. United States: N. p., 2017. Web. doi:10.1016/j.molcel.2017.06.034.
Qiao, Qi, Wang, Li, Meng, Fei-Long, Hwang, Joyce K., Alt, Frederick W., & Wu, Hao. AID Recognizes Structured DNA for Class Switch Recombination. United States. doi:10.1016/j.molcel.2017.06.034.
Qiao, Qi, Wang, Li, Meng, Fei-Long, Hwang, Joyce K., Alt, Frederick W., and Wu, Hao. 2017. "AID Recognizes Structured DNA for Class Switch Recombination". United States. doi:10.1016/j.molcel.2017.06.034.
@article{osti_1390862,
title = {AID Recognizes Structured DNA for Class Switch Recombination},
author = {Qiao, Qi and Wang, Li and Meng, Fei-Long and Hwang, Joyce K. and Alt, Frederick W. and Wu, Hao},
abstractNote = {},
doi = {10.1016/j.molcel.2017.06.034},
journal = {Molecular Cell},
number = 3,
volume = 67,
place = {United States},
year = 2017,
month = 8
}
  • In the currently popular organic-inorganic hybrid perovskite solar cells, the slowness of the charge recombination processes is found to be a key factor for contributing to their high efficiencies and high open circuit voltages, but the underlying recombination mechanism remains unclear. In this work, we investigate the bimolecular recombination (BR) and the trap-assisted monomolecular recombination (MR) in meso-structured perovskite solar cells under steady state working condition, and try to reveal their roles on determining the device performance. Some interfacial effects such as the injection barriers at the selective contacts are examined as well. Based on the macroscopic device modeling, themore » recombination resistance-voltage (R{sub rec}−V) and the current density-voltage (J–V) curves are calculated to characterize the recombination mechanism and describe the device performance, respectively. Through comparison with the impedance spectroscopy extracted R{sub rec} data, it is found that under the typical BR reduction factor and deep trap densities observed in experiments, the MR dominates the charge recombination in the low voltage regime, while the BR dominates in the high voltage regime. The short circuit current and the fill factor could be reduced by the significant MR but the open circuit voltage is generally determined by the BR. The different electron injection barriers at the contact can change the BR rate and induce different patterns for the R{sub rec}–V characteristics. For the perovskites of increased band gaps, the R{sub rec}'s are significantly enhanced, corresponding to the high open circuit voltages. Finally, it is revealed that the reduced effective charge mobility due to the transport in electron and hole transporting material makes the R{sub rec} decrease slowly with the increasing voltage, which leads to increased open circuit voltage.« less
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