From positive to negative magnetoresistance behavior at low applied magnetic fields for polyaniline:titania quantum dot nanocomposites

摘要: Here, we report the tuning from positive to negative magnetoresistance response at room temperature and low applied magnetic fields (H ∼ 200 mT) for polyaniline nancomposites prepared via in situ growth of titanium oxide quantum dots. In addition, showed experimental Raman evidence revealing that these nanocomposites is mediated by bipolaron mechanism. Confocal spectroscopy under field analysis decrease polaron population form bipolarons when exposed an TiO2 dot diluted regime. Negative magnetoresistance, observed higher concentration regime, was attributed suppression polarons probably associated with its partial chemical functionalization interface due increasing