Poly(ethylene imine) and Tetraethylenepentamine as Protecting Agents for Metallic Copper Nanoparticles

Abstract

The aim of this research was to explore the use of amine-containing polymeric and low-molar-mass organic protecting agents in the preparation of copper nanoparticles. Particles were synthesized using poly(ethylene imine) (PEI) or tetraethylenepentamine (TEPA) as protecting agents. The resulting particles were studied with UV-vis spectrometry, thermogravimetry, scanning electron microscopy, and transmission electron microscopy, wide-angle X-ray scattering with heating, X-ray photoelectron spectroscopy, and Auger electron spectroscopy. The average crystal sizes for the particles were at room temperature 8.5 and 19.4 nm for PEI and TEPA, respectively, and some surface oxidation was observed. The particles were sintered on paper, and the resistance and resistivity were measured. For Cu/PEI samples, the protecting agent was removed upon sintering at relatively low temperatures (between 150 and 200 degrees C). At this temperature range, particles exhibited a rapid increase in the crystal size. Sintered particles exhibited high conductivity, indicating that these kinds of materials might find use in paper-based printing.

Semiconductor-nanoparticle-donor nanochemical composites: Properties and applications as energy sources of the future

“…When NaBH 4 is added in small portions, the color changes from yellow to brown, which is interpreted as the formation of cop per nanoparticles protected with octanethiols [103]. As noted in [104], when NaBH 4 is added to Cu-PEI solution, the color gradually changes with time from red to green, blue, cyan, and purple magenta.…”

“…Studying copper nanoparticles is attractive and important in view of producing nanomaterials for electronics [103][104][105][106][107][108] due to the low cost of copper and its peculiar plasma properties and conductivity: the resistivity of bulk copper material is ~1.7 μΩ cm. Below, the properties of copper and gold nanoparticles are compared, because, as noted in [103], the methods of their synthesis are similar and based on chloride compounds in aqueous solutions where NaBH 4 acts as a reducing agent.…”

“…When copper nanoparticles are syn thesized, CuCl 2 is taken and the protective shells are amine (tetraethylenepentamine, TEPA) or imine (polyethylenimine, PEI) polymers or octanethiols (OT). During reduction of copper chlorides with NaBH 4 [103,104], the solution color varies in a broad spectral range. In the absence of the reducing agent, the solution is black, which characterizes mixed valence states of copper particles.…”

Facile preparation of L-ascorbic acid-stabilized copper-chitosan nanocomposites with high stability and antimicrobial properties

“…In particular, the smaller the nanoparticles are, the more easily they become oxidized. To overcome these obstacles, researchers have used inert gas and different sorts of polymers [17,18] as dispersants to protect Cu NPs during the synthesis process. Lactic acid [19] and iodine [20] have also been used as protecting agents.…”

Carboxymethylated chitosan-stabilized copper nanoparticles: a promise to contribute a potent antifungal and antibacterial agent

“…Among the different reported approaches, the widely accepted solution-based chemical precipitation method generally involves the precipitation of Cu-NPs or Cu-nanocomposites through reduction of copper salts at optimal precursor concentrations under inert atmosphere (Ar or N 2 ). Here the particle size of Cu-NPs is manipulated by controlling the process parameters, whereas their stability is often achieved through the use of various stabilizing agents (added in appropriate solvent medium), such as starch (Valodkar et al 2012), gelatin (Chatterjee et al 2012), chitosan (Usman et al 2013), sodium dodecyl sulfate (Soomro et al 2013), cetyltrimethylammonium bromide (Wu and Chen 2004), and so on (Mott et al 2007;Song et al 2004;Zhang et al 2014;Pulkkinen et al 2009;Wang and Asefa 2010;Giuffrida et al 2008;Sarkar et al 2008;Deng et al 2013). Their presence in solvent medium during the preparation not only helps in preventing surface oxidation of the Cu-NPs to form Cu 2 O and CuO but also helps in controlling their particle size to obtain stable, colloidal dispersions.…”