%0 Journal Article %A Hu, Xuan %A Phillips, Patrick J %A Mazumdar, Dipanjan %A Idrobo, Juan Carlos %A Kolesnik, Stanislaw %A Gupta, Arunava %D 2017 %T Atomic and electronic structure of Ti substitution in Ca3Co4O9 %U https://indigo.uic.edu/articles/journal_contribution/Atomic_and_electronic_structure_of_Ti_substitution_in_Ca3Co4O9/10750943 %2 https://indigo.uic.edu/ndownloader/files/19262045 %K Atoms %K Calcium %K Cobalt %K Transmission electron microscopy %X We examine the role of Ti doping in the incommensurately layered thermoelectric oxide material Ca3Co4O9 (CCO). The measured Seebeck coefficient of S = 135 µV /K in Ti-doped CCO thin films of composition Ca3Co3.8Ti0.2O9 indicates no significant enhancement of S compared to pristine CCO, thus confirming prior experimental results. Using a combination of aberration-corrected scanning transmission electron microscopy, electron energy-loss spectroscopy and first-principles computations, we determine the atomic and electronic structures of Ti-doped CCO, including the preferred location of Ti dopants and valence states of Ti and Co atoms. Our findings on the structural, electronic and transport properties of the Ti-doped CCO are discussed in light of previously published results %I University of Illinois at Chicago