Key Words:High-k dielectric;Crystalline materials - Dielectric properties - Electric fields - Electrorheological fluids - Metal nanoparticles - Nanofluidics - Organometallics - Rheology - Silicones - Synthesis (chemical) - Titanium - Titanium dioxide;Cetyltrimethylammonium bromide - Dielectric spectra - Electrorheological - Electrorheological performance - Large surface area - Solvothermal method - TiO2 nano-particles - Titanium metals

Abstract:A simple method for synthesis of porous TiO<inf>2</inf>nanoparticles was developed via a two-step route using titanium metal-organic framework (MOF) as a precursor, in which MOFs were first prepared by a cetyltrimethylammonium bromide (CTAB) assisted solvothermal method and then calcined in air at 500 &deg;C. After pyrolysis of precursor MOFs, the anatase TiO<inf>2</inf>inherited the porosity of precursor MOF and possessed a large surface area and uniform pore distribution, which was subsequently adopted as an electrorheological (ER) material by dispersing in silicone oil. ER activities of MOFs and porous TiO<inf>2</inf>based suspensions under the applied electric fields were investigated in a controlled shear rate (CSR) mode. In contrast to MOFs based ER fluids, the suspension of porous TiO<inf>2</inf>exhibited a higher ER efficiency and lower leakage current. Furthermore, the improvement of dielectric properties was found to be responsible for the enhanced ER activity through an investigation of dielectric spectrum.<br/> Copyright &copy; 2018 American Chemical Society.

Volume:57

Issue:20

Translation or Not:no