10.1002/anie.201713415
Angewandte Chemie International Edition
COMMUNICATION
transistors modified with TFMBT thiol (0.086 cm2V-1s-1). The
increased OFET performance should be attributed to the
decreased contact resistance induced by: a) the increased grain
size at the IPr-Au/pentacene interface; and b) the enhanced
charge injection as a result of the IPr-assembling on the Au
surface. In summary, we have demonstrated that IPr is an
exceptionally valuable alternative to thiols as a modifier on the
Au surface in the application of OFET devices.
Table 2. The charge carrier mobilites () and calculated work functions for
gold surfaces modified with three NHCs.[7e]
Work Function
NHCs
Au
Chemical Structure
/cm2V-1s-1
/eV
---
5.17
3.0E-2
N
N
Acknowledgements
IPr
4.13
1.5E-1
We thank Sebastian Lamping for analytical support. This work
was supported by the Germany–China Joint Project TRR61
(DFG–NSFC
Transregio
Project),
the
Deutsche
Forschungsgemeinschaft (SFB 858 and Leibniz Award), the
National Natural Science Foundation of China (91227201,
21527805, 21661132006),the Program for Professor of Special
Appointment (Eastern Scholar) at Shanghai Institutions of
Higher Learning. Generous financial support by the Alexander
von Humboldt Foundation (K.M.C.) is gratefully acknowledged.
iPr2bimy
3.90
7.8E-2
N
N
N
N
IiPr
3.84
5.0
4.5E-2
---
Keywords: carbene • surface modification • OFETs • contact
resistance • Au electrodes
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