TY - JOUR
T1 - Investigation of the high electron affinity molecular dopant f6-tcnnq for hole-transport materials
AU - Zhang, Fengyu
AU - Kahn, Antoine
N1 - Funding Information:
Funding of this work by the National Science Foundation under grant DMR-1506097 is gratefully acknowledged. The authors are grateful to Novaled GmbH Dresden for providing the dopant F6-TCNNQ and for fruitful discussions aided by funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 646176.
Publisher Copyright:
© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
PY - 2018/1/4
Y1 - 2018/1/4
N2 - 2,2′-(perfluoronaphthalene-2,6-diylidene)dimalononitrile (F6-TCNNQ) is investigated as a molecular p-type dopant in two hole-transport materials, 2,2′,7,7′-tetrakis(N,N-diphenylamino)-9,9-spirobifluorene (Spiro-TAD) and tris(4-carbazoyl-9-ylphenyl)amine (TCTA). The electron affinity of F6-TCNNQ is determined to be 5.60 eV, one of the strongest organic molecular oxidizing agents used to date in organic electronics. p-Doping is found to be effective in Spiro-TAD (ionization energy = 5.46 eV) but not in TCTA (ionization energy = 5.85 eV). Optical absorption measurements demonstrate that charge transfer is the predominant doping mechanism in Spiro-TAD:F6-TCNNQ. The host– dopant interaction also leads to a significant alteration of the host film morphology. Finally, transport measurements done on Spiro-TAD:F6-TCNNQ as a function of dopant concentration and temperature, and using a highly doped contact layer to ensure negligible hole injection barrier, lead to an accurate measurement of the film conductivity and hole-hopping activation energy.
AB - 2,2′-(perfluoronaphthalene-2,6-diylidene)dimalononitrile (F6-TCNNQ) is investigated as a molecular p-type dopant in two hole-transport materials, 2,2′,7,7′-tetrakis(N,N-diphenylamino)-9,9-spirobifluorene (Spiro-TAD) and tris(4-carbazoyl-9-ylphenyl)amine (TCTA). The electron affinity of F6-TCNNQ is determined to be 5.60 eV, one of the strongest organic molecular oxidizing agents used to date in organic electronics. p-Doping is found to be effective in Spiro-TAD (ionization energy = 5.46 eV) but not in TCTA (ionization energy = 5.85 eV). Optical absorption measurements demonstrate that charge transfer is the predominant doping mechanism in Spiro-TAD:F6-TCNNQ. The host– dopant interaction also leads to a significant alteration of the host film morphology. Finally, transport measurements done on Spiro-TAD:F6-TCNNQ as a function of dopant concentration and temperature, and using a highly doped contact layer to ensure negligible hole injection barrier, lead to an accurate measurement of the film conductivity and hole-hopping activation energy.
KW - Conductivity
KW - Electronic structures
KW - Organic semiconductors
KW - P-doping
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U2 - 10.1002/adfm.201703780
DO - 10.1002/adfm.201703780
M3 - Article
AN - SCOPUS:85035107018
SN - 1616-301X
VL - 28
JO - Advanced Functional Materials
JF - Advanced Functional Materials
IS - 1
M1 - 1703780
ER -