TY - JOUR
T1 - Charge transfer-induced horizontal orientation of organic molecules near transition metal oxide surfaces
AU - Matsushima, Toshinori
AU - Murata, Hideyuki
N1 - Funding Information:
The authors are grateful to Prof. Chihaya Adachi and Dr. Shuzo Hirata (Kyusyu University) for α-NPD deposition on a substrate cooled at −150 °C and to Grants-in-Aid for Scientific Research of Japan (Grant Nos. 21760005, 20241034, and 20108012) for financial support. This research is supported by the Japan Society for the Promotion of Science (JSPS) through its “Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program)”.
PY - 2013/4
Y1 - 2013/4
N2 - The influence of charge transfer from organic molecules to transition metal oxide on molecular orientation characteristics of N,N′-diphenyl-N, N′-bis(1-naphthyl)-1,1′-biphenyl-4,4′-diamine (α-NPD) was investigated. Absorption peaks originating from neutral and cationic states of α-NPD increased in absorbance when α-NPD was deposited on metal oxides (MoO2, MoO3, and WO3). Photoluminescence from this α-NPD was directional normal to the film plane. These results indicate that α-NPD is horizontally oriented near the metal oxide surfaces so that charge transfer from α-NPD to metal oxide occurs efficiently. Such horizontal orientation of α-NPD enhanced current density of hole-only α-NPD devices because of improvement of wave function overlap and charge transfer degree at the metal oxide/α-NPD interface.
AB - The influence of charge transfer from organic molecules to transition metal oxide on molecular orientation characteristics of N,N′-diphenyl-N, N′-bis(1-naphthyl)-1,1′-biphenyl-4,4′-diamine (α-NPD) was investigated. Absorption peaks originating from neutral and cationic states of α-NPD increased in absorbance when α-NPD was deposited on metal oxides (MoO2, MoO3, and WO3). Photoluminescence from this α-NPD was directional normal to the film plane. These results indicate that α-NPD is horizontally oriented near the metal oxide surfaces so that charge transfer from α-NPD to metal oxide occurs efficiently. Such horizontal orientation of α-NPD enhanced current density of hole-only α-NPD devices because of improvement of wave function overlap and charge transfer degree at the metal oxide/α-NPD interface.
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U2 - 10.1016/j.orgel.2013.01.038
DO - 10.1016/j.orgel.2013.01.038
M3 - Article
AN - SCOPUS:84874935415
SN - 1566-1199
VL - 14
SP - 1149
EP - 1156
JO - Organic Electronics
JF - Organic Electronics
IS - 4
ER -