writer：Zhenjie Zhao，Xiao Jin，Yongri Liang，Li-Min Wang，Ying Dan Liu*
keywords：Ionic Liquid
source：期刊
specific source：ACS Applied Nano Materials, 2022, 5(12), 17928-17938
Issue time：2022年
TiO2 nanoparticles modified by ionic liquid (IL), which are called inorganic ionogels, have shown improved electroresponsive electrorheological (ER) characteristics due to the contribution of IL to the polarizability and conductivity of the nanoparticles. However, the IL on the particle surface readily generates a large current density under high-strength electric fields, limiting the further application of IL-containing electroresponsive materials. In this study, 1, 3-disulfonic acid imidazolium chloride ([Dsim]Cl) ionic liquid and acetic acid (AA) dual-modified TiO2 nanoparticles (TiO2-[Dsim]Cl-AA) were fabricated to solve this problem without significantly reducing the ER properties of the nanoparticles. The morphologies and structures of the TiO2-[Dsim]Cl-AA nanoparticles modified with different amounts of AA were synthesized and investigated. The rheological analysis indicated that the TiO2 ionogel nanoparticles modified by an appropriate amount of AA can effectively reduce the leakage current density of the ER fluid. With a relatively low particle volume fraction of 25%, the ER fluid showed ultrahigh yield stress up to 128 kPa and low zero-field viscosity of 7 Pa·s. In addition, the ER fluid also showed a stable ER effect in a broad temperature range of 5–85 °C and a slow sedimentation rate with time. The IL and AA dual-modified TiO2 nanoparticles with an ultrahigh yield stress, broad working temperature range, and high antisettling stability will be excellent ER candidates for practical application.