Direct Ordering of Anchoring Events at the Surface of Iron Oxide Nanoparticles Enabled by A Stepwise Phase-Transfer Strategy

摘要

For most nanoparticle applications, understanding the "strength" of anchoring events at the surface is necessary to design effective ligand exchange processes. The present report demonstrates the ability to direct the ordering of phosphonic acid, catechol, and carboxylic acid as anchoring groups for iron oxide nanoparticles, enabled by a stepwise phase-transfer strategy. A key feature was the use of a cyclohexane-based thermomorphic system that provided a unique homogeneous field for ligand-exchange processes, where hydrophobic nanoparticles and a hydrophilic ligand, or hydrophilic nanoparticles and a hydrophobic ligand, effectively mixed together within a moderate temperature range.