Nonequilibrium Green's function study of Pd4-cluster-functionalized carbon nanotubes as hydrogen sensors
Citation:
C. Cao, A. F. Kemper, L. Agapito, J.-W. Zhang, Y. He, A. Rinzler, H.-P. Cheng, X.-G. Zhang, A.R. Rocha, and Stefano Sanvito, Nonequilibrium Green's function study of Pd4-cluster-functionalized carbon nanotubes as hydrogen sensors, Physical Review B, 79, 2009, 075127Download Item:
PhysRevB.79.075127.pdf (Published (publisher's copy)) 626.7Kb
Abstract:
Pd-cluster-functionalized carbon nanotubes
CNTs
have been shown experimentally to be effective hydro-
gen sensors. Semiconducting CNTs exhibit much higher sensitivity than ensemble
mixed
ones. Using the
nonequilibrium Green?s function method combined with the density-functional theory, we simulate and con-
trast the
8,0
semiconducting and the
5,5
metallic CNT model systems. We find that the electron localization
effect plays a crucial role in determining electron transport. Pd clusters and hydrogen adsorption cause opposite
effects on electron localization in the CNT backbone for the semiconducting CNT-based systems. Conse-
quently Pd functionalization dramatically increases the conductance, but then it is strongly suppressed by
hydrogen absorption. For the metallic CNT-based systems, there is a tiny shift of the transmission peak near the
Fermi energy. These results offer a consistent explanation for the experiments
Sponsor
Grant Number
Department of Energy
FG02- 02ER45995
Author's Homepage:
http://people.tcd.ie/sanvitosDescription:
PUBLISHED
Author: SANVITO, STEFANO
Sponsor:
Department of EnergyType of material:
Journal ArticleCollections:
Series/Report no:
Physical Review B79
Availability:
Full text availableSubject:
PhysicsSubject (TCD):
Nanoscience & MaterialsDOI:
http://dx.doi.org/10.1103/PhysRevB.79.075127The following license files are associated with this item: