A Versatile Method for Synthesis of Light-Activated, Magnet-Steerable Organic-Inorganic Hybrid Active Colloids.

The immense potential of active colloids in practical applications and fundamental research calls for an efficient method to synthesize active colloids of high uniformity. Herein, a facile method is reported to synthesize uniform organic-inorganic hybrid active colloids based on the wetting effect of polystyrene (PS) with photoresponsive inorganic nanoparticles in a tetrahydrofuran/water mixture. The results show that a range of dimer active colloids can be produced by using different inorganic components, such as AgCl, ZnO, TiO, and FeO nanoparticles.

Synthesis of Rod-Shaped ZnO/Polysiloxane Micromotors with Patch-Dependent Motion Modes.

Inorganic particles with photocatalytic properties are excellent candidates for the fabrication of micromotors. To achieve self-propulsion, the geometric and chemical symmetries of inorganic particles should be broken. However, the synthesis of micromotors with different geometric and chemical symmetries remains challenging.

Motor and Rotor in One: Light-Active ZnO/Au Twinned Rods of Tunable Motion Modes.

Precise control of the motion of micromachines is the key to achieving their functions for practical applications. The main challenge is that a given micromachine can typically exhibit only one motion mode, i.e.

Phototactic Flocking of Photochemical Micromotors.

Inspired by astonishing collective motions and tactic behaviors in nature, here we show phototactic flocking of synthetic photochemical micromotors. When enriched with hydroxyl groups, TiO micromotors can spontaneously gather into flocks in aqueous media through electrolyte diffusiophoresis. Under light irradiation, due to the dominant nonelectrolyte diffusiophoretic interaction resulting from the overlap of asymmetric nonelectrolyte clouds around adjacent individuals, these flocks exhibit intriguing collective behaviors, such as dilatational negative phototaxis, high collective velocity, and adaptive group reconfiguration.

Synthesis of Polystyrene Particles with Precisely Controlled Degree of Concaveness.

Shape is an essential property of polymeric particles. Herein, we propose a simple method to synthesize polymeric particles with a well-controlled concave shape. Our method takes advantage of the powerful seeded emulsion polymerization strategy with the well-known principle of "like dissolves like" in solvent chemistry.

New insights into the formation mechanism of gold nanoparticles using dopamine as a reducing agent.

Dopamine (DA), a simplified mimic of mussel proteins, can be employed as a reductant in the preparation of Au nanoparticles (AuNPs) due to its inherent catechol building block. The widely accepted mechanism of AuNP formation using DA as the reductant assumes that the reduction of Au(III) ions involves the two-electron oxidation of DA, where the corresponding phenol and phenolates serve as the reductive species to yield quinone. We herein report a novel insight into the mechanism of formation of AuNPs using DA as the reductant.

Mussel-inspired one-pot synthesis of a fluorescent and water-soluble polydopamine-polyethyleneimine copolymer.

Inspired by the molecular mechanics of mussel adhesive formation, a novel water-soluble fluorescent macromolecule (polydopamine-polyethyleneimine (PDA-PEI)) is prepared by one-pot copolymerization of dopamine (DA) and PEI. In this method, DA is polymerized to form PDA, which is then coupled with PEI mainly through Michael addition. The fluorescence property of PDA-PEI is mainly attributed to the Michael addition of PEI on the 5,6-dihydroxyindole (DHI) units of PDA, where PEI can form hydrogen bonds with oxidative products such as DHI and force the DHI units to twist out of plane, resulting in a decrease in the intra- and intermolecular coupling of PDA.