Self‐Propelled Structural Color Cylindrical Micromotors for Heavy Metal Ions Adsorption and Screening

Abstract

Water contamination resulting from heavy metal ions (HMIs) poses a severe threat to public health and the ecosystem. Attempts are tending to develop functional materials to realize efficient and intelligent adsorption of HMIs. Herein, self‐propelled structural color cylindrical micromotors (SCCMs) with reversible HMIs adsorption capacity and self‐reporting property are presented. The SCCMs are fabricated by using platinum nanoparticles (Pt NPs) tagged responsive hydrogel of carboxymethyl chitosan (CMC) and polyacrylamide (PAM) to asymmetrically replicate tubular colloidal crystal templates (TCCTs). Owing to the self‐propelled motion of the SCCMs, the enhancive ion–motor interactions bring significantly improved decontamination efficiency. Moreover, it is demonstrated that the SCCMs can realize quick and naked‐eye‐visible self‐reporting during the adsorption/desorption process based on their responsive structure color variation and superior adsorption capacity. Thus, it is anticipated that such intelligent SCCMs can significantly facilitate the evolution of sensing assays and diverse environmental fields.

Magnetic photonic crystals for biomedical applications

“…The top-down strategy mainly relies on traditional microfabrication techniques such as lithography, etching, chemical evaporation, and deposition, which directly manufacture micro/nanostructures with the aid of high-precision computer-assisted instruments. [38][39][40][41][42][43][44][45][46] However, such a manner has been restricted due to the high cost, complex operations, and limited nanoscale precision. In contract, the bottom-up strategy, mainly referred as self-assembly, could achieve synthesis of hierarchical highly-ordered PhC architectures (one-, two-, and three-dimension) with low cost, high efficiency, and delicate nanoscales, as schemed in Figure 2A.…”

“…Recently, diverse methods have been proposed to replicate the periodic photonic structures of PhCs, which can be roughly divided into two classifications: top‐down and bottom‐up strategy. The top‐down strategy mainly relies on traditional microfabrication techniques such as lithography, etching, chemical evaporation, and deposition, which directly manufacture micro/nanostructures with the aid of high‐precision computer‐assisted instruments 38–46 . However, such a manner has been restricted due to the high cost, complex operations, and limited nanoscale precision.…”

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

“…Active colloids are synthetic microparticles that can convert various forms of energy, such as light [ 1 , 2 , 3 , 4 , 5 ], chemical [ 6 , 7 ], magnetic [ 8 , 9 ], electrical [ 10 , 11 ], and acoustic energy [ 12 ] into mechanical motion. Active colloids are found many applications at the microscale, including cargo delivery [ 5 , 13 , 14 ], biosensing [ 15 ], pollution monitoring [ 16 , 17 ], and environmental remediation [ 18 , 19 ], as well as acting as model systems to study the physics of active matter [ 20 , 21 ]. Holding the key to the success of active colloids in both applications and fundamental research is an efficient method to synthesize active colloids of high uniformity in large quantities.…”

Magnetic Manganese‐Based Micromotors MnFe2O4@Fe3O4/graphite and Mn2O3@Fe2O3@Fe3O4/graphite for Organic Pollutant Degradation

“…[19,20] The wide research interest in micro/nanomotors is associated with the fact that they can be used to solve many applied problems in medicine, [21] environmental applications. [22,23] For the decomposition of organic compounds, hydrogen peroxide (H 2 O 2 ) is often used, which can perform several functions. On the one hand, hydrogen peroxide is a fuel for micro/nanomotors.…”