Green Synthesis and Characterization of Gold Nanoparticles Using Lignin Nanoparticles.

Jiachuan Chen,Guigan Fang,Baobin Wang,Guihua Yang

doi:10.3390/nano10091869

Abstract

With the development of nanotechnology, gold nanoparticles (Au NPs) have attracted enormous attention due to their special properties. The green synthesis of Au NPs from lignin would inspire the utilization of lignin and its related functional materials. In this study, a rapid preparation process of Au NPs was investigated by utilizing lignin nanoparticles (LNPs) under room temperature without chemical addition. The LNPs acted as a reducing agent, stabilizing agent, and template for the preparation of LNPs@AuNPs. The obtained LNPs@AuNPs were characterized by UV-Vis spectrum, Transmission Electron Microscope (TEM), and X-ray photoelectron spectroscopy (XPS). The possible mechanism was illustrated by Fourier Transform Infrared Spectroscopy (FT-IR), 31P, XPS, and UV analyses. The abundant hydroxyl groups (24.96 mmol/g) favored the preparation of Au NPs. Au NPs diameters of 10–30 nm were well dispersed in the LNPs. The optimal reaction conditions were a ratio of 10 mg of LNPs to 0.05 mmol HAuCl4, room temperature, and a reaction time of 30 min. The LNPs@AuNPs exhibited excellent stability in the suspension for more than seven days. The reduction process could be related to the disruption of side chains of lignin, hydroxyl group oxidation, and hydroquinones and quinones from the comproportionation reaction. The LNPs@AuNPs would open a door for the design of Au NP/lignin-derived novel functional materials.

Highlights

With The development of nanotechnology and nanoscience, metal nanoparticles have attracted enormous attention because of their novel optical/electrical properties [1,2]
The Au NPs were well dispersed in The lignin nanoparticles (LNPs) due to The stabilizing effect of The lignin
The prehydrolysis lignin (PL) was dissolved in ethanol first, and deionized water was added as an anti-solvent to obtain LNPs

Summary

Introduction

With The development of nanotechnology and nanoscience, metal nanoparticles have attracted enormous attention because of their novel optical/electrical properties [1,2]. A more environmentally friendly procedure is needed to prepare The Au NPs. Lignin, The most abundant aromatic, is a biopolymer derived from trees and crops [11]. In The past decade, researchers found that The 3D structure and abundant surface groups (hydroxyl, carbonyl, and aldehyde groups) could act as reducing and stabilizing agents for The green synthesis of metal nanoparticles. Various approaches were applied in The green synthesis of metal nanoparticles including microwave irradiation, mechanical grinding method, and heat reduction. The green synthesis of well-dispersed Au NPs with LNPs is important for The preparation of composite lignin-derived materials. LNPs were utilized as reducing and stabilizing agents for The green synthesis of well-dispersed LNPs@AuNPs under room temperature. Au NPs were confined in The LNP structure which would facilitate The design of The lignin-based materials.

Materials

Preparation of LNP

Characterization

Results