Assembling PNIPAM-Capped Gold Nanoparticles in Aqueous Solutions

Year: 2023

Type: article

Abstract: Employing small-angle X-ray scattering (SAXS), we explore the conditions under which assembly of gold nanoparticles (AuNPs) grafted with the thermosensitive polymer poly( N -isopropylacrylamide) (PNIPAM) emerges. We find that short-range order assembly emerges by combining the addition of electrolytes or polyelectrolytes with raising the temperature of the suspensions above the lower-critical solution temperature (LCST) of PNIPAM. Our results show that the longer the PNIPAM chain is, the better organization in the assembled clusters. Interestingly, without added electrolytes, there is no evidence of AuNPs assembly as a function of temperature, although untethered PNIPAM is known to undergo a coil-to-globule transition above its LCST. This study demonstrates another approach to assembling potential thermosensitive nanostructures for devices by leveraging the unique properties of PNIPAM.

Source: ACS Macro Letters

DOI: 10.1021/acsmacrolett.3c00617

Authors: Binay P. Nayak, Hyeong Jin Kim, Srikanth Nayak, Wenjie Wang, Wei Bu, Surya K. Mallapragada, David Vaknin

Institutions: Iowa State University, Ames National Laboratory, University of Chicago

Language: English

Topic: Gold and Silver Nanoparticles Synthesis and Applications

Subfield: Electronic, Optical and Magnetic Materials

Field: Materials Science

Domain: Physical Sciences

Open Access status: green

Funders: National Science Foundation, U.S. Department of Energy, Iowa State University, Office of Science, Division of Materials Research, Division of Chemistry, Basic Energy Sciences, Argonne National Laboratory, Division of Materials Sciences and Engineering

OpenAlex ID: W4388897022