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

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 arornaticity and chirality of ferrocenyl and L-Ala, this organic molecule self-assembled into a single helix structure through intermolecule hydrogen bonds and pi-pi 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 O-2 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).