Chen Shucheng, Guo Chun Xian, Zhao Qipeng, Lu Xianmao
Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585 (Singapore), Fax: (+65) 6779-1936.
Chemistry. 2014 Oct 20;20(43):14057-62. doi: 10.1002/chem.201403411. Epub 2014 Sep 5.
CO2-responsive nanoparticles have been attracted increasing interest due to their benign reactions with CO2 that give them gas-switchable properties, which can be easily reversed by mild heating or purging with inert gases. In this work, we have prepared CO2-responsive magnetic nanoparticles in a simple one-pot polyol synthesis using diaminoalkanes as the surfactant. The as-synthesized nanoparticles show excellent reversible aggregation and dispersion in response to alternating purging of N2 and CO2 at room temperature. We found that, among the diaminoalkanes with different chain lengths, 1,8-diaminooctane is the best candidate for the synthesis of CO2-responsive nanoparticles, since it allows good dispersity of the nanoparticles after charging with CO2 and also provides effective aggregation and separation following N2 purging. Moreover, the self-assembly of 1,8-diaminooctane-functionalized nanoparticles can be controlled to form linear aggregates with the assistance of N2 and an external magnetic field, demonstrating an effective response to dual stimuli. This work paves the way for the direct synthesis of a wide range of CO2-responsive nanoparticles.
