Building HKUST-1 metal organic frameworks on board of Cu tubular micromotors with adaptative propulsive capabilities

Abstract

Herein we present one step simplified synthesis of tubular Cu micromotors based on Hong Kong University of Science and Technology (HKUST-1) metal organic frameworks (MOF). Tubular Cu/Pt, Cu/Ni and Cu/Ni/Pt micromotors prepared by template electrodeposition are smartly used as nucleation spots for the synthesis of HKUST-1 MOFs by incubation with the specific ligand, benzene-1,3,5-tricarboxylic acid, without any harsh conditions. The inner engines impart the micromotors with adaptative propulsion mechanisms for future applications: magnetic, catalytic, and hybrid magnetic and catalytic modes, reaching speeds of up to 275 µm s-1. Furthermore, stability studies reveal the increased stability of the HKUST-1 MOFs in the micromotors as compared with the free MOFs. The destruction of the HKUST-1 MOFs in water has been exploited for compounds encapsulation and controlled release, as illustrated using fluorescein as model molecule. The range of applications for this new generation of MOF-based micromotors is endless due to the physical and chemical properties of these materials.