TY - JOUR
T1 - Coherent Electron Transport across a 3 nm Bioelectronic Junction Made of Multi-Heme Proteins
AU - Futera, Zdenek
AU - Ide, Ichiro
AU - Kayser, Ben
AU - Garg, Kavita
AU - Jiang, Xiuyun
AU - Van Wonderen, Jessica H.
AU - Butt, Julea N.
AU - Ishii, Hisao
AU - Pecht, Israel
AU - Sheves, Mordechai
AU - Cahen, David
AU - Blumberger, Jochen
N1 - Publisher Copyright: © 2020 American Chemical Society.
PY - 2020/11/19
Y1 - 2020/11/19
N2 - Multi-heme cytochromes (MHCs) are fascinating proteins used by bacterial organisms to shuttle electrons within, between, and out of their cells. When placed in solid-state electronic junctions, MHCs support temperature-independent currents over several nanometers that are 3 orders of magnitude higher compared to other redox proteins of similar size. To gain molecular-level insight into their astonishingly high conductivities, we combine experimental photoemission spectroscopy with DFT+ς current-voltage calculations on a representative Gold-MHC-Gold junction. We find that conduction across the dry, 3 nm long protein occurs via off-resonant coherent tunneling, mediated by a large number of protein valence-band orbitals that are strongly delocalized over heme and protein residues. This picture is profoundly different from the electron hopping mechanism induced electrochemically or photochemically under aqueous conditions. Our results imply that the current output in solid-state junctions can be even further increased in resonance, for example, by applying a gate voltage, thus allowing a quantum jump for next-generation bionanoelectronic devices.
AB - Multi-heme cytochromes (MHCs) are fascinating proteins used by bacterial organisms to shuttle electrons within, between, and out of their cells. When placed in solid-state electronic junctions, MHCs support temperature-independent currents over several nanometers that are 3 orders of magnitude higher compared to other redox proteins of similar size. To gain molecular-level insight into their astonishingly high conductivities, we combine experimental photoemission spectroscopy with DFT+ς current-voltage calculations on a representative Gold-MHC-Gold junction. We find that conduction across the dry, 3 nm long protein occurs via off-resonant coherent tunneling, mediated by a large number of protein valence-band orbitals that are strongly delocalized over heme and protein residues. This picture is profoundly different from the electron hopping mechanism induced electrochemically or photochemically under aqueous conditions. Our results imply that the current output in solid-state junctions can be even further increased in resonance, for example, by applying a gate voltage, thus allowing a quantum jump for next-generation bionanoelectronic devices.
UR - http://www.scopus.com/inward/record.url?scp=85096457054&partnerID=8YFLogxK
U2 - https://doi.org/10.1021/acs.jpclett.0c02686
DO - https://doi.org/10.1021/acs.jpclett.0c02686
M3 - مقالة
C2 - 33142062
SN - 1948-7185
VL - 11
SP - 9766
EP - 9774
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 22
ER -