Processing of Cr doped SrTiO3 nanoparticles into high surface area aerogels and thin films

Abstract

We present the nonaqueous sol–gel synthesis of crystalline SrTi_1−xCr_xO₃ (x = 0, 0.3, 2, 5, 10%) nanoparticles and their processing into highly concentrated dispersions in ethanol by surface functionalization with 2-[2-(2-methoxyethoxy) ethoxy] acetic acid (MEEAA). These stable nanoparticle dispersions can then be assembled into 2- and 3-dimensional architectures such as films and aerogels. Homogeneous transparent films with a compact microstructure and a thickness of 140 nm are prepared from the dispersion by dip coating, while efficient destabilization and supercritical drying results in nanostructured bulk aerogels with a high surface area of up to 370 m² g⁻¹.