Core-Shell-Structured Electrorheological Fluid with a Polarizability-Tunable Nanocarbon Shell for Enhanced Stimuli-Responsive Activity

The incorporation of nanocarbon-based materials intoelectrorheologicalfluids has been shown to be an effective means of improving the electrorheological(ER) response. However, the mechanism of the sp(2)/sp(3)-hybridized carbon structure and high ER response is stillunder investigation. Herein, barium titanate@nanocarbon shell (BTO@NCs)composites are proposed and prepared by introducing carbonized polydopamine(C-PDA) into a shell. When the polymerization time of dopamine istuned, the shell thickness, surface polar functional groups, and sp(2)/sp(3)-hybridized carbon can be effectively controlled.The maximum yield stress of the BTO@NCs-24 h ER fluid reaches 2.5kPa under an electric field of 4 kV mm(-1), whichis attributed to the increased content of sp(3) C-OHand oxygenous functional groups within the shell, resulting in a rapidlyachievable polarization. Furthermore, the SiO2@NCs andTiO(2)@NCs ER fluids are also prepared with enhanced ER behaviorin these phenomena, confirming an approach to high-performance ERfluids based on nanocarbon composites.

Automated summary

In this study, barium titanate@nanocarbon shell (BTO@NCs) composites were prepared by introducing carbonized polydopamine (C-PDA) into the shell, effectively controlling the shell thickness, surface polar functional groups, and sp(2)/sp(3) hybridized carbon content. The maximum yield stress of BTO@NCs-24 h ER fluid reached 2.5 kPa under an electric field of 4 kV mm(-1) due to the increased content of sp(3) C-OH and oxygenous functional groups within the shell, resulting in a rapidly achievable polarization. Additionally, SiO2@NCs and TiO2@NCs ER fluids were also prepared, confirming the approach to high-performance ER fluids based on nanocarbon composites.