Shape-Controlled Synthesis of Organometallic Microcrystal-Based Hollow Hexagonal Micromotors through Evaporation-Induced Supramolecular Self-Assembly

Abstract

A facile strategy was developed to fabricate structure controllable microcrystals of ferrocene-based metal–organic (Fc-Ala-BCB) materials through evaporation-induced self-assembly. Two distinctive microcrystals, microrods and microtubes had been achieved by tuning the solvents during the self-assemblies. X-ray diffraction analysis was conducted on single crystals to investigate the packing mode of Fc-Ala-BCB molecules, which indicated the two crystals with the hexagonal system. Inheriting the aromaticity and chirality of ferrocenyl and l-Ala, this organic molecule self-assembled into a single-helix structure through intermolecule hydrogen bonds and π–π stacking. Theoretical analysis and stimulated computations were carried out to compare the surface energies of certain planes. Among those microcrystals, the microrods exhibited a higher chemical activity in catalyzing the decomposition of H2O2, due to the high-density atomic steps and kinks on the high energy surfaces. However, the hollow hexagonal tubes displayed appropriate catalytic activity and novel maneuverability toward catalyzing H2O2. The O2 bubbles accumulated at the inner walls of the microtube were periodically released as individual bubbles, suggesting their potential application as a new kind of microengine (e.g., the microrotor).

Synthesis of flower‐like Bi2S3/Cu7.2S4 composites and their photocatalytic performance

“…Further extending the reaction time, the ultrathin nanosheets are grown into large nanosheets (Figure b‐c). With the progress of the mass diffusion and Ostwald ripening process, nanosheets form accompanied by way of self‐organization into the flower‐like structure through a nucleation dissolution recrystallization . Finally, the microspheres were constructed into hierarchical Bi 2 S 3 /Cu 7.2 S 4 composite spherical structures.…”

Geometry Design, Principles and Assembly of Micromotors

“…Other impressive fabrication methods include different components in oil-in-water droplets, followed by emulsification, solidification and direct assembly of asymmetric catalytic/magnetic NMs [ 71 ]. Examples of other methods are Co-Pt/Au motors with a three-step applied electrochemical potential process [ 72 ], shape-controlled fabrication of the polymer-based motors based on the polydimethylsiloxane template [ 73 ], template electrosynthesis of graphene microengines [ 74 ], layer-by-layer assembly technique in combination with micro-contact printing [ 75 ], evaporation-induced self-assembly using controllable crystals of ferrocene-based metal–organic (Fc-Ala-BCB) materials [ 76 ], and polymer NMs with doped Pt nanoparticles/carbon nanotubes [ 77 ].…”

Synthesis of Catalytic Microswimmers Based on Anisotropic Platinum Sorption on Melamine Barbiturate Supramolecular Structures

“…[15] Similarly to cells, they can change location under external chemical or physical changes in the environment thus providing autonomous movement. [16][17][18] Furthermore, supramolecular architectures have a wide potential as a replacement for complex synthetic molecules, for example, they are great candidates for artificial motors. They can be obtained by straightforward synthesis mechanisms, where constituent parts can be modulated sophisticatedly toward a wide range of applications.…”