# A Facile One-Pot Preparation and Catalytic Application of Tunable Silica-Coated Aqueous Gold Nanoparticles

## TL;DR

This paper introduces a simple method to create tunable gold nanoparticles using a special polymer, which can also act as a catalyst.

## Contribution

The study presents a one-pot method using TMSP-PEI polymer for synthesizing, stabilizing, and protecting gold nanoparticles.

## Key findings

- Gold nanoparticles with varying sizes and shapes were synthesized using TMSP-PEI without additional reducing agents.
- Adjusting the metal-to-ligand ratio and solvent environment influenced nanoparticle morphology and size distribution.
- The nanoparticles showed catalytic activity in reducing Eosin Y without degradation.

## Abstract

It is known that designer polymers can be used for the synthesis and stabilization of metallic nanoparticle systems, providing new, tailorable properties. In this work, we demonstrate the trifold utility of a designer polymer, trimethoxysilylpropyl-(polyethylenimine) (TMSP-PEI), providing reduction, stabilization, and protection in a single step. Our facile and unique synthesis affords gold nanoparticles with varying sizes and morphologies in a range of solvents without the need for additional reducing agents. The use of this substituted polymer was manipulated in terms of the metal-to-ligand ratio to induce changes in the nanoparticle nucleation and growth. Upon further experimental analysis, it was discovered that adjustments to not only the metal–ligand ratio but also the solvent environment produced nanoparticles with different shape and size distributions. In addition, the synthesized gold nanoparticles were investigated for their catalytic ability to reduce Eosin Y in the presence of sodium borohydride without degradation.