A new and facile way to fabricate catalytically active block copolymer/Au nanoparticle multilayer thin films at the air/liquid interface

Abstract

A composite polymer/Au nanoparticle multilayer film was fabricated at the air/liquid interface through a new and facile self-assembly and adsorption process. A planar liquid/liquid interface was formed at first by using a DMF/CHCl 3 mixed solution of polybutadiene-block-poly(4-vinylpyridine) (PB-b-P4VP) as the lower phase and a HAuCl 4 aqueous solution as the upper phase, respectively. The PB-b-P4VP molecules self-organized into disk-like micelles in the mixed organic phase. Owing to the intersolubility of water and DMF, DMF carried the block copolymer molecules and micelles into the upper aqueous phase, and then diffused into the HAuCl 4 aqueous solution, leading to further self-assembly of the polymer molecules with the inorganic species and the formation of larger sheet aggregates.These aggregates further adsorbed at the air/liquid interface, resulting in the formation of the multilayer composite film. Most AuCl 4 − ions were reduced by DMF during this process, and numerous Au nanoparticles were generated and embedded in the composite film. This film exhibited unique heterogeneous catalytic properties due to its unique multilayer structure.

Synthesis of Gold Nanoparticles Using Mimosa tenuiflora Extract, Assessments of Cytotoxicity, Cellular Uptake, and Catalysis

“…AuMt1 has a half population of NPs with size less to 40 nm, while AuMt2 NPs have a mean diameter of 150 nm, determined by TEM. Peak shift for Au4 f signals, due to the presence of small NPs, has been reported by other authors who relate the Au4 f BE increase with decreasing NP size [64, 65]. Also, the shift effect could be due to the interaction of functional groups capped on surfaces of AuNPs [66].…”

Lamellar Nanosheets of Water-Insoluble Amphiphiles via Aqueous Solution and Air/Liquid Interface Self-Assembly

“…On the basis of the results and our previous works, − the formation process of the lamellar nanosheets in method I is illustrated in Scheme A. DMF, perhaps with a small amount of chloroform, carried a large number of PCDA molecules from the bottom phase and entered into the upper phase across the liquid/liquid interface as soon as the interface formed, due to ouzo effect.…”

“…The aqueous droplets entered into the organic phase, while the organic droplets (mainly DMF) entered into the aqueous phase, leading to the formation of emulsions . Because of the miscibility between DMF and water, the DMF molecules in the droplets diffused into water rapidly, and then the amphiphilic block copolymer molecules escaped from the droplets and self-assembled into ordered aggregates, such as a rodlike micelle , and multilayer, which further adsorbed at the air/liquid interface to form thin films. This method was then extended to fabricate superstructures of metal nanoparticles by using aqueous dispersions of nanoparticles as the upper phase and chloroform/DMF solutions of ligands, such as fatty amines, as the bottom phase, respectively .…”

Organic–inorganic hybrid nanomaterials prepared via polymerization-induced self-assembly: recent developments and future opportunities

“…[17][18][19][20][21] In particular, the cooperative self-assembly of polymers and inorganic nanoparticles in solution has proved to be one of the most efficient methods to prepare organic-inorganic hybrid nanomaterials with unique structures and properties. [22][23][24][25][26][27][28][29][30] However, the cooperative self-assembly method is usually conducted in a highly dilute solution (<1% w/w) with multi-step processes, which is not beneficial for the large-scale preparation and application of organic-inorganic hybrid nanomaterials.…”