Band-Like Carrier Transport at the Single-Crystal Contact Interfaces between 2,5-Difluoro-7,7,8,8-tetracyanoquinodimethane and Electron Donors

Takuro Shimada; Yukihiro Takahashi; Jun Harada; Hiroyuki Hasegawa; Tamotsu Inabe

doi:10.1021/acs.jpclett.7b03053

Band-Like Carrier Transport at the Single-Crystal Contact Interfaces between 2,5-Difluoro-7,7,8,8-tetracyanoquinodimethane and Electron Donors

J Phys Chem Lett. 2018 Jan 18;9(2):420-424. doi: 10.1021/acs.jpclett.7b03053. Epub 2018 Jan 11.

Authors

Takuro Shimada¹, Yukihiro Takahashi^{1

2}, Jun Harada^{1

2}, Hiroyuki Hasegawa³, Tamotsu Inabe^{1

2}

Affiliations

¹ Graduate School of Chemical Sciences and Engineering, Hokkaido University , Sapporo 060-0810, Japan.
² Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo 060-0810, Japan.
³ Kobe Advanced ICT Research Institute, National Institute of Information and Communications Technology , Kobe 651-2492, Japan.

PMID: 29298071
DOI: 10.1021/acs.jpclett.7b03053

Abstract

Some heterojunction interfaces formed with molecular solids show metal-like transport behavior. In order to clarify the requirement, interfaces are fabricated by lamination of single-crystal electron-accepting 2,5-difluoro-7,7,8,8-tetracyanoquinodimethane (F₂TCNQ) and electron-donating molecules with a wide range of ionization potentials. Carrier injection between the acceptor and donor crystals leads to highly conducting interfaces, some of which exhibited band-like charge transport behaviors. Combinations with weak donors also resulted in interfaces with band-like transport properties. Accordingly, band-like conduction was achieved for interfaces where the donor and acceptor crystals do not have well-matched band energies. The results indicate that the wide range of candidates have great potential for modification of the electronic structure of organic crystals. The present method is expected to enable control of the electronic properties of the interface.