First Principles Insights into Oxide/polymer Composites:Srtio3/polyaniline/graphene

A detailed computational investigation,based on density functional theory,of the interaction of polyani-line(PANI)and graphene nanoribbons(GNRs)with SrTiO3 is presented.The adsorption of PANI in var-ious oxidation states and co-adsorption with GNRs is found to be thermodynamically favourable.Ad-sorbed PANI introduces N and C 2p states into the SrTiO3 bandgap,while co-adsorption of PANI and GNRs leads to a bridging of the gap and semi-metallic behaviour,thus rendering the electrical properties highly sensitive to the loading of the GNRs/PANI in the composites.Modelling the lattice dynamics of the composites predicts a 68-88％reduction in the lattice thermal conductivity due to reduced phonon group velocities.Taken together,these findings provide insight into the growing number of experimental studies highlighting the enhanced thermoelectric performance of oxide-polymer composites and indicate co-adsorption with graphene as a facile direction for future research.