TY - JOUR
T1 - Interplay of Fermi Level Pinning, Marcus Inverted Transport, and Orbital Gating in Molecular Tunneling Junctions
AU - Kang, Hungu
AU - Kong, Gyu Don
AU - Byeon, Seo Eun
AU - Yang, Sena
AU - Kim, Jeong Won
AU - Yoon, Hyo Jae
N1 - Funding Information:
This research was supported by the National Research Foundation of Korea (2019R1A2C2011003 and 2019R1A6A1A11044070 for H.J.Y.; 2017R1A2B4012086 for J.W.K.). The NEXAFS spectroscopy experiment was performed at the 4D beamline of Pohang Light Source, Republic of Korea.
PY - 2020/10/15
Y1 - 2020/10/15
N2 - This Letter examines the interplay of important tunneling mechanisms-Fermi level pinning, Marcus inverted transport, and orbital gating-in a molecular rectifier. The temperature dependence of the rectifying molecular junction containing 2,2′-bipyridyl terminated n-alkanethiolate was investigated. A bell-shaped trend of activation energy as a function of applied bias evidenced the dominant occurrence of unusual Marcus inverted transport, while retention of rectification at low temperatures implied that the rectification obeyed the resonant tunneling regime. The results allowed reconciling two separately developed transport models, Marcus-Landauer energetics and Fermi level pinning-based rectification. Our work shows that the internal orbital gating can be substituted with the pinning effect, which pushes the transport mechanism into the Marcus inverted regime.
AB - This Letter examines the interplay of important tunneling mechanisms-Fermi level pinning, Marcus inverted transport, and orbital gating-in a molecular rectifier. The temperature dependence of the rectifying molecular junction containing 2,2′-bipyridyl terminated n-alkanethiolate was investigated. A bell-shaped trend of activation energy as a function of applied bias evidenced the dominant occurrence of unusual Marcus inverted transport, while retention of rectification at low temperatures implied that the rectification obeyed the resonant tunneling regime. The results allowed reconciling two separately developed transport models, Marcus-Landauer energetics and Fermi level pinning-based rectification. Our work shows that the internal orbital gating can be substituted with the pinning effect, which pushes the transport mechanism into the Marcus inverted regime.
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U2 - 10.1021/acs.jpclett.0c02509
DO - 10.1021/acs.jpclett.0c02509
M3 - Article
C2 - 32976711
AN - SCOPUS:85093538538
VL - 11
SP - 8597
EP - 8603
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
SN - 1948-7185
IS - 20
ER -