Indexed by:期刊论文

Date of Publication:2019-08-20

Journal:COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS

Included Journals:SCIE、EI

Volume:575

Page Number:94-101

ISSN No.:0927-7757

Key Words:Hybrid microgels; Plasmonic nanoparticles; In situ reduction; Polyampholyte; Polyol; Polyamine

Abstract:We demonstrate the applicability and versatility of recently developed epoxy-amine microgels toward the synthesis of gold nanoparticles through chemical reduction of tetrachloroauric (III) acid (HAuCl4). The reaction takes place in water under mild heating, and is free from extra reducing and stabilizing agents with both functions fulfilled by the amine groups of the microgels, making it a green process. Interestingly, results of transmission electron microscopy, infrared spectroscopy, and thermogravimetric analysis show that, despite the mild reaction conditions, hydroxyl groups of the microgels also mediate HAuCl4 reduction and in turn radically change chemical functionality as well as structure of the microgels. This effect is believed to be enabled by the overall basicity of the microgels. With the combined actions of amine and hydroxyl, versatile outcomes ranging from Au nanoparticle hybridized amphoteric microgels to assembly of Au nanoparticles can be achieved simply by varying the mass ratios of microgels to HAuCl4 from high to low. Further characterizations of the plasmonic amphoteric hybrids with UV-vis absorption spectroscopy and dynamic light scattering show their good storage stability and responsiveness to pH. The process reported herein can not only diversify the options available for the synthesis of gold nanoparticles, but also advance the development of functional hybrids integrating properties of plasmonic nanomaterials with amphoteric microgels.