TY - JOUR
T1 - A molybdenum dithiolene complex as p-dopant for hole-transport materials
T2 - A multitechnique experimental and theoretical investigation
AU - Qi, Yabing
AU - Sajoto, Tissa
AU - Kröger, Michael
AU - Kandabarow, Alexander M.
AU - Park, Wunjun
AU - Barlow, Stephen
AU - Kim, Eung Gun
AU - Wielunski, Leszek
AU - Feldman, L. C.
AU - Bartynski, Robert A.
AU - Brédas, Jean Luc
AU - Marder, Seth R.
AU - Kahn, Antoine
PY - 2010/1/26
Y1 - 2010/1/26
N2 - Molybdenum tris-[l ,2-bis(trifluoromethyl)ethane-l,2-dithiolene] (Mo(tfd) 3) is investigated as a P-dopant for organic semiconductors. With an electron affinity of 5.6 eV, Mo(tfd) 3 is a strong oxidizing agent suitable for the oxidation of several hole transport materials (HTMs). Ultraviolet photoemission spectroscopy confirms -doping of the standard HTM N,N-di-[(l-naphthyl)-N,N-diphenyl]-l, l'biphenyl-4,4'-diamine (a-NPD). Strong enhancement of hole injection at a-NPD/Au interfaces is achieved via doping-induced formation of a narrow depletion region in the organic semiconductor. Variable-temperature current-voltage measurements on a-NPD: Mo(tfd) 3 (0-3.8 mol%) yield an activation energy for polaron transport that decreases with increasing doping concentration, which is consistent with the effect of the doping-induced filling of traps on hopping transport. Good stability of Mo(tfd)3 versus diffusion in the a-NPD host matrix is demonstrated by Rutherford backscattering for temperatures up to 110 °C. Density functional theory (DFT) calculations are performed to obtain geometries and electronic structures of isolated neutral and anionic Mo(tfd) 3 molecules.
AB - Molybdenum tris-[l ,2-bis(trifluoromethyl)ethane-l,2-dithiolene] (Mo(tfd) 3) is investigated as a P-dopant for organic semiconductors. With an electron affinity of 5.6 eV, Mo(tfd) 3 is a strong oxidizing agent suitable for the oxidation of several hole transport materials (HTMs). Ultraviolet photoemission spectroscopy confirms -doping of the standard HTM N,N-di-[(l-naphthyl)-N,N-diphenyl]-l, l'biphenyl-4,4'-diamine (a-NPD). Strong enhancement of hole injection at a-NPD/Au interfaces is achieved via doping-induced formation of a narrow depletion region in the organic semiconductor. Variable-temperature current-voltage measurements on a-NPD: Mo(tfd) 3 (0-3.8 mol%) yield an activation energy for polaron transport that decreases with increasing doping concentration, which is consistent with the effect of the doping-induced filling of traps on hopping transport. Good stability of Mo(tfd)3 versus diffusion in the a-NPD host matrix is demonstrated by Rutherford backscattering for temperatures up to 110 °C. Density functional theory (DFT) calculations are performed to obtain geometries and electronic structures of isolated neutral and anionic Mo(tfd) 3 molecules.
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U2 - 10.1021/cm9031623
DO - 10.1021/cm9031623
M3 - Article
AN - SCOPUS:75249102537
SN - 0897-4756
VL - 22
SP - 524
EP - 531
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 2
ER -