Soft-x-ray photoemission spectroscopy and ab initio studies on the adsorption of NO2 molecules on defective multiwalled carbon nanotubes.
The adsorption of NO(2) molecules on defective multiwalled carbon nanotubes has been studied by soft-x-ray photoemission. The valence band and carbon core-level spectra have been acquired before, during, and after NO(2) exposure. The spectra show a reversible decrease of the density of states at the top of the valence band when NO(2) molecules are adsorbed on the (carbon nanotubes) CNTs. No shift of the C 1s spectra has been observed. Theoretical calculations, using density-functional theory, have been performed on the CNT + NO(2) system, considering semiconducting nanotubes with different diameters and introducing a Stone-Wales [Chem. Phys. Lett. 128, 501 (1986)] defect. The calculation confirms the decrease of the density of states at the top of the valence band in the CNT + NO(2) system, while close to the adsorption site new states appear very close to the Fermi level.
Lozzi
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Istituto Nazionale per la Fisica della Materia-Consiglio Nazionale delle Ricerche (INFM-CNR) and Department of Physics, University of L'Aquila, Coppito, Italy. luca.lozzi@aquila.infn.it
Picozzi
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Armentano
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Valentini
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Kenny
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JM
La Rosa
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Coreno
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de Simone
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Delley
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B
Santucci
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