Electronic Structure and Chemical Nature of Oxygen Dopant States in

Sep 29, 2014 - of a highly emissive deep trap state below ... chemically stable sites with remarkably .... spectra of different electronic states in u...
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Electronic Structure and Chemical Nature of Oxygen Dopant States in Carbon Nanotubes Xuedan Ma,† Lyudmyla Adamska,‡ Hisato Yamaguchi,† Sibel Ebru Yalcin,† Sergei Tretiak,†,‡ Stephen K. Doorn,*,† and Han Htoon*,† †

Center for Integrated Nanotechnologies, Materials Physics and Applications Division, ‡Theory Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States

ABSTRACT We performed low temperature photoluminescence (PL) studies

on individual oxygen-doped single-walled carbon nanotubes (SWCNTs) and correlated our observations to electronic structure simulations. Our experiment reveals multiple sharp asymmetric emission peaks at energies 50300 meV redshifted from that of the E11 bright exciton peak. Our simulation suggests an association of these peaks with deep trap states tied to different specific chemical adducts. In addition, oxygen doping is also observed to split the E11 exciton into two or more states with an energy splitting