Effect of electrosteric stabilization of TiO2 nanoparticles on photophysical properties of organic/inorganic hybrid nanocomposite

Abstract

Hybrid organic/inorganic nanocomposites are considered one of the most significant research areas due to their enhanced optoelectronic properties. This article is a detailed investigation of the effect of stabilization and dispersion of titanium dioxide (TiO2) nanoparticles on the photophysical properties of the conjugated polymer, (poly(2-methoxy-5-(2-ethylhexyloxy)1,4-phenylenevinylene (MEH-PPV). To obtain a colloidally stable nanoparticle dispersion, electrosteric stabilization of TiO2 in the MEH-PPV matrix is attempted. This work demonstrates the efficient electrostatic stabilization of TiO2 nanoparticle dispersion based on pH, zeta potential, and synthesis route. Further steric stabilization was achieved through in situ polymerization of MEH-PPV on the surface of TiO2 nanoparticles, which further reduced the van der Waal force of attraction (VFA). As a result of the combination of electrostatic and steric (electrosteric) stabilization, MEH-PPV: TiO2 hybrid nanocomposites with reduced polymer defects were successfully produced, resulting in improved absorbance, reduced non-radiative recombination rates, and long-term stability.