TY - JOUR
T1 - Overdamping Carrier Transport and Quantitative Thermodynamic Analyses of Traps in Organic Semiconductor NPB
AU - Liu, Rui Lan
AU - Tang, Chao
AU - Huang, Wei
N1 - Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/11/21
Y1 - 2019/11/21
N2 - The impedance spectroscopy (IS) based on the physical mathematical equation can be used to investigate the carrier dynamics in organic semiconductors (OSCs). However, most of the previous related works have ignored the influence of the superimposed alternating signal on the carrier mobility. In this report, serious physical derivation has been carried out to achieve the IS model, which considers the trapping of the charge as a function of the frequency. Then, a second-order differential equation was incorporated to approximate the trap item and interpret trap-limited carrier transport, which at last accurately fitted the experimental data of N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) films with clear physical meanings. The results also show that the trap-limited carrier transports in NPB are all overdamping transport, which should be ascribed to the polaron-phonon carrier transport in OSCs. After the thermodynamic analyses, since the overdamping coefficients originated from the trap items in the physical IS model, the values can be reasonably correlated with the trap effect of OSCs.
AB - The impedance spectroscopy (IS) based on the physical mathematical equation can be used to investigate the carrier dynamics in organic semiconductors (OSCs). However, most of the previous related works have ignored the influence of the superimposed alternating signal on the carrier mobility. In this report, serious physical derivation has been carried out to achieve the IS model, which considers the trapping of the charge as a function of the frequency. Then, a second-order differential equation was incorporated to approximate the trap item and interpret trap-limited carrier transport, which at last accurately fitted the experimental data of N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) films with clear physical meanings. The results also show that the trap-limited carrier transports in NPB are all overdamping transport, which should be ascribed to the polaron-phonon carrier transport in OSCs. After the thermodynamic analyses, since the overdamping coefficients originated from the trap items in the physical IS model, the values can be reasonably correlated with the trap effect of OSCs.
UR - http://www.scopus.com/inward/record.url?scp=85074717735&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.9b06711
DO - 10.1021/acs.jpcc.9b06711
M3 - 文章
AN - SCOPUS:85074717735
SN - 1932-7447
VL - 123
SP - 28015
EP - 28020
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 46
ER -