Electrical conductivity enhancement in polyaniline films via mixed ion‐electron conductive fillers.

The influence of mixed ion‐electronic conductive fillers on the physical characteristics of protonated polyaniline (P‐PANI) nanocomposite films is investigated by incorporating titanium nanoparticles (TiNPs) and lithium trifluoromethanesulfonate (LiOTf) at various concentrations. The introduction of TiNPs into the P‐PANI matrix results in the appearance of additional X‐ray diffraction peaks ascribed to a titanium phase, confirming the presence of TiNPs. The incorporation of LiOTf leads to changes in intensities, linewidths, and diffraction angles, indicating interactions between Li+ ions and nitrogen atoms in the PANI matrix. The bandgap energy for the pristine P‐PANI film is 3.40 eV, being reduced to 3.29 eV upon incorporating TiNPs in the P‐PANI matrix. An increase in the concentration of LiOTf in the P‐PANI/TiNPs composite films with decreasing TiNPs concentration leads to a continuous increase in bandgap energy to 3.59 eV. The electrical conductivity of pristine P‐PANI is 0.49 mS/cm. The addition of TiNPs increases the conductivity to 2.16 mS/cm, while the addition of LiOTf increases it to 1.72 mS/cm. Notably, (P‐PANI)/TiNPs nanocomposite films with 7:3 and 5:5 wt.% ratios exhibit superior electrical conductivity compared with individual (P‐PANI)/TiNPs and (P‐PANI)/LiOTf films, attributed to effective ionic‐electronic coupling at phase‐separated region interfaces. This study reveals impact of TiNPs and LiOTf on the structural, optical, and electrical properties of P‐PANI nanocomposite films, thereby enhancing their potential for integration into advanced electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]