TY - JOUR
T1 - Asymmetric electron and hole transport in a high-mobility n-type conjugated polymer
AU - Wetzelaer, Gert Jan A.H.
AU - Kuik, Martijn
AU - Olivier, Yoann
AU - Lemaur, Vincent
AU - Cornil, Jérôme
AU - Fabiano, Simone
AU - Loi, Maria Antonietta
AU - Blom, Paul W.M.
PY - 2012/10/18
Y1 - 2012/10/18
N2 - Electron- and hole-transport properties of the n-type copolymer poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2, 6-diyl]-alt-5,5′-(2,2′-dithiophene)} [P(NDI2OD-T2), PolyeraActivInk™ N2200] are investigated. Electron- and hole-only devices with Ohmic contacts are demonstrated, exhibiting trap-free space-charge-limited currents for both types of charge carriers. While hole and electron mobilities are frequently equal in organic semiconductors, room-temperature mobilities of 5 × 10 -8 m2/Vs for electrons and 3.4 × 10 -10 m2/Vs for holes are determined, both showing universal Arrhenius temperature scaling. The origin of the large difference between electron and hole mobility is explained by quantum-chemical calculations, which reveal that the internal reorganization energy for electrons is smaller than for holes, while the transfer integral is larger. As a result, electron transport is intrinsically superior to hole transport under the same injection and extraction conditions.
AB - Electron- and hole-transport properties of the n-type copolymer poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2, 6-diyl]-alt-5,5′-(2,2′-dithiophene)} [P(NDI2OD-T2), PolyeraActivInk™ N2200] are investigated. Electron- and hole-only devices with Ohmic contacts are demonstrated, exhibiting trap-free space-charge-limited currents for both types of charge carriers. While hole and electron mobilities are frequently equal in organic semiconductors, room-temperature mobilities of 5 × 10 -8 m2/Vs for electrons and 3.4 × 10 -10 m2/Vs for holes are determined, both showing universal Arrhenius temperature scaling. The origin of the large difference between electron and hole mobility is explained by quantum-chemical calculations, which reveal that the internal reorganization energy for electrons is smaller than for holes, while the transfer integral is larger. As a result, electron transport is intrinsically superior to hole transport under the same injection and extraction conditions.
UR - http://www.scopus.com/inward/record.url?scp=84867771848&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.86.165203
DO - 10.1103/PhysRevB.86.165203
M3 - Article
AN - SCOPUS:84867771848
SN - 1098-0121
VL - 86
JO - Physical Review. B, Condensed Matter and Materials Physics
JF - Physical Review. B, Condensed Matter and Materials Physics
IS - 16
M1 - 165203
ER -