Shear-thickening electrolytes are of increasing interest, as they offer potentially enhanced battery safety during extreme impact. Current shear-thickening electrolytes consist of a suspension of spherical nanoparticles in battery electrolyte media, but these tend to be effective only at high loadings and do not display discontinuous shear thickening. Accordingly, the present challenge is to maximize the shear-thickening effect at the lowest particle loading. Here, anisotropic silica nanorods with aspect ratios ranging from 2 to 24 are explored as alternatives to the current paradigm of spherical nanoparticles for shear-thickening electrolytes. As the aspect ratio increases, the critical volume fraction for shear thickening decreases. Discontinuous shear thickening in which solidification takes place is achieved by using nanorods of aspect ratio 24 at the relatively low volume fraction of 0.146. Interparticle attractions originating from the interaction between the nanorod's solvation layer and the electrolyte cause hysteresis in the critical shear stress for shear thickening. Moreover, interparticle attractions increase with decreasing aspect ratio, which is attributed to the increasing surface area of the silica nanorods. Therefore, shear thickening is due to the combined effects of particle aspect ratio, interparticle attractions, hydrodynamic forces, and frictional contacts. A rheological state diagram is created for future materials design, and ballistic tests demonstrate a 37% reduction in blunt force due to the shear-thickening electrolyte.

Polymer-derived Janus particles, both polymeric and composites of organic and inorganic components, hold promise as key elements in future applications due to their unique morphologies and functionalities. In this Perspective, recent progress in the synthesis and generation of polymer-derived Janus particles at the single-chain, nanoscopic, and macroscopic length scales is described. We focus on significant achievements in the control of distinct compartmentalization and large-scale synthesis of Janus nanoparticles, both of which are crucial for their practical use. The challenges and opportunities associated with polymer-derived Janus particles are outlined to inspire the development of new strategies for the large-scale synthesis of Janus particles with integrated functionalities.

Single chain nanoparticles are obtained by intramolecular metallic coordination in concentrated solutions at ambient temperature.

We report the large‐scale synthesis of photoluminescent single‐chain nanoparticles (SCNPs) by electrostatic‐mediated intramolecular crosslinking in a concentrated solution of 40 mg mL−1 by continuous addition of the free radical initiator. Poly(vinyl benzyl chloride) was charged by quaternization with vinyl‐imidazolium for the intramolecular crosslinking by using 2,2‐dimethoxy‐2‐phenylacetophenone (DMAP) as the radical initiator. Under the electrostatic repulsion thus interchain isolation, the intrachain crosslinking experiences the transition from coil through pearl‐necklace to globular state. The SCNPs demonstrate strong photoluminescence in the visible range when the non‐emissive units are confined thereby. Composition and microstructure of the SCNPs are tunable. The photoluminescent tadpole‐like Janus SCNP can be used to selectively illuminate interfacial membranes while stabilizing the emulsions.

Constructing precisely oriented assemblies and exploring their orientation-dependent properties remain a challenge for Janus nanoparticles (JNPs) due to their asymmetric characteristics. Herein, we propose a bubble-driven instant quasi-1D interfacial strategy for the oriented assembly of JNP chains in a highly controllable manner. It is found that the rapid formation of templated bubbles can promote the interfacial orientation of JNPs kinetically, while the confined quasi-1D interface in the curved liquid bridge can constrain the disordered rotation of the particles, yielding well-oriented JNP chains in a long range. During the evaporation process, the interfacial orientation of the JNPs can be transferred to the assembled chains. By regulating the amphiphilicity of the JNPs, both heteraxial and coaxial JNP assemblies are obtained, which show different polarization dependences on light scattering, and the related colorimetric logic behaviors are demonstrated. This work demonstrates the great potential of patterned interfacial assembly with a manageable orientation and shows the broad prospect of asymmetric JNP assembly in constructing novel optoelectronic devices.