TY - JOUR
T1 - The electronic structure of porphyrin/metal interfaces studied by UV photoemission spectroscopy
AU - Yoshumira, D.
AU - Ishii, H.
AU - Narioka, S.
AU - Sei, M.
AU - Miyazaki, T.
AU - Ouchi, Y.
AU - Hasegawa, S.
AU - Harima, Y.
AU - Yamashita, K.
AU - Seki, K.
N1 - Funding Information:
This work was supported in part by Grant-in-Aids for Scientific Research from the Ministry of Education, Science, Sports, and Culture of Japan (Nos. 07NPO302, 07CE2004, and OSCE2004) and Venture Business Laboratory Project of Nagoya University. This work was performed as a Joint Studies Program of the WSOR facility of Institute for Molecular Science (No.6~H2 17).
PY - 1997/2/28
Y1 - 1997/2/28
N2 - The electronic structures of the interface between porphyrin and metal (Mg, Al, Ag and Au) were studied by UV photoemission spectroscopy (UPS). The samples were 5,10,15,20-tetraphenylporphynatozinc(ZnTPP), 5,10,15,20-tetra(4-pyridyl) porphyrin(H2T(4-Py)P) and 5,10,15,20-tetra-phenylporphyrin(H2TPP) which are known as organic semiconductors. We found that the energy levels of these porphyrins relative to the Fermi level of the substrate metals could be expressed as linear functions of the work function of metals with a shift of the vacuum level at interface (delta sign). This indicates that the energy levels of these porphyrins are fixed to the vacuum level of substrate metal with an interfacial dipole layer. We also found that the magnitude of delta sign is constant at ZnTPP/metal interfaces, but depends on the work function of the metal at H2T(4-Py)P and H2TPP/metal interfaces. This work function dependence of delta sign might be explained by the existence of interface state.
AB - The electronic structures of the interface between porphyrin and metal (Mg, Al, Ag and Au) were studied by UV photoemission spectroscopy (UPS). The samples were 5,10,15,20-tetraphenylporphynatozinc(ZnTPP), 5,10,15,20-tetra(4-pyridyl) porphyrin(H2T(4-Py)P) and 5,10,15,20-tetra-phenylporphyrin(H2TPP) which are known as organic semiconductors. We found that the energy levels of these porphyrins relative to the Fermi level of the substrate metals could be expressed as linear functions of the work function of metals with a shift of the vacuum level at interface (delta sign). This indicates that the energy levels of these porphyrins are fixed to the vacuum level of substrate metal with an interfacial dipole layer. We also found that the magnitude of delta sign is constant at ZnTPP/metal interfaces, but depends on the work function of the metal at H2T(4-Py)P and H2TPP/metal interfaces. This work function dependence of delta sign might be explained by the existence of interface state.
KW - Organic semiconductor based on conjugated molecules
KW - Organic/inorganic interfaces
KW - Photoelectron spectroscopy
KW - Solar cells
UR - http://www.scopus.com/inward/record.url?scp=0040098296&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0040098296&partnerID=8YFLogxK
U2 - 10.1016/s0379-6779(97)81177-0
DO - 10.1016/s0379-6779(97)81177-0
M3 - Article
AN - SCOPUS:0040098296
SN - 0379-6779
VL - 86
SP - 2399
EP - 2400
JO - Synthetic Metals
JF - Synthetic Metals
IS - 1-3
ER -