Microwave-assisted synthesis of gold nanoparticles self-assembled into self-supported superstructures

Abstract

Passivated gold nanoparticles were synthesized through a microwave-assisted process in a two-phase system, in the presence of 1-dodecanethiol. An average particle size of 1.8 nm of the gold nanoparticles obtained and 0.35 S.D. was determined through HRTEM and STEM analysis. It was observed that these nanoparticles spontaneously self-assemble into self-supported superstructures of 1 μm in diameter avg and 400 nm thickness, yielding an off-white powder which can be handled as a simple powder. XRD analysis indicates that n-alkanethiol molecules used as a passivating compound, besides protecting against crystal growth, interact to form cubic ordered arrays between the nanoparticles. This interaction leads to the superstructure formation, with an average distance between nanoparticles in the array, of 3.56 nm. Theoretical calculations and molecular dynamics simulations were performed to analyze the resulting structure.

Green Synthesis of Gold Nanoparticles Using Carrageenan Oligosaccharide and Their In Vitro Antitumor Activity

“…The HRTEM result of CAO-AuNPs (Figure 5D) not only showed a clear ellipsoidal shape, but also displayed the distribution of the lattice of AuNPs that was consistent with the FCC structure of gold [10,20,31], which indicated that the obtained AuNPs are crystal structures. The zeta potential (ZP) of CAO-AuNPs was determined to be −20 mV, indicating that the CAO-AuNPs had a high negatively charged surface, which could be beneficial for the delivery of positively charged drugs [2,35].…”

Revisiting the conformational adsorption of L‐ and D‐cysteine on Au nanoparticles by Raman spectroscopy

“…Tetrachloroauric acid (HAuCl 4 · 3H 2 O ≥99.9 % ) was purchased from Sigma Aldrich and used without further purification. Au NPs were synthesized according to a previously reported method with some modifications . Nucleation of small NPs (∼ 0.7–1.3 nm) was induced in an ETHOS EZ microwave digestion system with a microwave frequency of 2.5 GHz.…”

A Review Article on Muscular Dystrophy and Its Management Through Ayurveda

“…[30,31] Microwave irradiation method was embraced to synthesize AuNPs by using citric acid as a reducing agent and cetyltrimethyl ammonium bromide (CTAB) as a binding agent. [32] In addition, other utilized physical technique such as ultrasonic waves, laser ablation, solvothermal method and electrochemical methods are available in literature for synthesis of AuNPs.…”