Chemical anchoring of silica nanoparticles onto polyaniline chains via electro-co-polymerization of aniline and N-substituted aniline grafted on surfaces of SiO2

Chemical anchoring of silica nanoparticles onto polyaniline (PANI) chains was conducted through electro-co-polymerization of aniline and N-substituted aniline grafted on surfaces of silica nanoparticles. The grafting of N-substituted aniline on surfaces of silica nanoparticles were realized through hydrolysis of triethoxysilylmethyl N-substituted aniline (ND42) and the following condensation reaction with silanol groups on surfaces of SiO₂. Organic-inorganic interactions between PANI and SiO₂ involved in electro-co-polymerization process pushed the polymer chains apart and so facilitated the 1D growth of the polymer. Hence, the obtained hybrid film PANI/ND42-SiO₂ displayed nano-fibrous morphologies (ca. 50 nm in diameter). Consequently, PANI/ND42-SiO₂ exhibited an average specific capacitance of 380 F g⁻¹, ca. 40% higher than that of PANI/SiO₂ (276 F g⁻¹). The hybrid film also showed improved cyclic stability.