Controlled growth of metallic copper nanoparticles. (2nd November 2017)

• Record Type: Journal Article
• Authors: Boita, Jocenir; Nicolao, Lucas; Alves, Maria C. M.; Morais, Jonder
• Is Part Of: New journal of chemistry. Volume 41:Number 23(2017)
• Page Start: 14478
• Page End: 14485
• Publication Date: 2017-11-02
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c7nj03056h
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : We report a polyol synthesis method that provides controlled growth of chemically stable Cu nanoparticles with mean diameter easily tuned to lie below 10 nm. Abstract : We present a comprehensive characterization of Cu nanoparticles (NPs) synthesized by a polyol method, combining ethylene glycol, copper chloride, polyvinylpyrrolidone, sodium citrate and ascorbic acid. This simple and low cost synthesis results in a colloid containing nearly-monodispersed metallic NPs. Our investigation enabled two important stages to be distinguished during the growth reaction: (1) the first, revealed by in situ time resolved dispersive X-ray absorption spectroscopy (XAS), corresponds to a fast reduction/nucleation and early growth of metallic NPs, later corroborated by ex situ XAS measurements. The resulting Cu nanoparticles have a mean diameter of 1.5 ± 0.8 nm, as determined by TEM; (2) the second stage, monitored by TEM, HRTEM and XRD measurements, corresponds to a slow aggregation growth where the mean volume grows linearly with time with a rate of 2.1 ± 0.3 nm 3 per day – proceeding while the NPs are kept in the colloidal solution. Such slow growth rate allows the aging time to be used for tuning the NP size; nevertheless, we show that size dispersion also increases with time following a similar rate.