Abstract
Amines are used extensively as reductants and subsequent capping agents in the synthesis of metal nanoparticles, especially gold, due to its affinity to nitrogen. Taking 2-methyl aniline as an example, we show that metal reduction is followed by polymerization of the amine, while part of it covers the nanoparticle surface another fraction deposits in the solution. It is found that the oxidative polymerization of the amine goes in step with the formation of gold nanoparticles. The gold nanoparticles thus formed have a mean diameter of 20 nm. The polymerized amine encapsulates the gold nanoparticle forming a robust shell of about 5 nm thickness, making the gold core inert towards mineralizing agents such as chloroform, bromoform, sodium cyanide, benzylchloride, etc. which react with the naked gold nanoparticles. The deposited polymer is largely protonated, taking up protons from the medium during its formation. Similar results have been observed in the case of aniline also. The materials have been fully characterized by spectroscopy and microscopy.
Similar content being viewed by others
References
E.M. Andrade F.V. Moline M.I. Florit D. Posadas (1996) ArticleTitleIR response of poly(o-toluidine): Spectral modifications upon redox state change Electroanal. Chem. 419 15–21 Occurrence Handle10.1016/S0022-0728(96)04874-7
M. Aslam L. Fu M. Su K. Vijayamohanan V.P. Dravid (2004) ArticleTitleNovel one-step synthesis of amine-stabilized aqueous colloidal gold nanoparticles J. Mater. Chem. 14 1795–1797 Occurrence Handle10.1039/b402823f
M. Brust M. Walker D. Bethell DJ. Schiffrin R. Whyman (1994) ArticleTitleSynthesis of thiol-derivatised gold nanoparticle in a two-phase liquid–liquid system J. Chem. Soc. Chem. Commun. 7 801–802 Occurrence Handle10.1039/c39940000801
P. Colombian A. Gruger A. Novak A. Regis (1994) ArticleTitleInfrared and Raman study of polyaniline Part I. Hydrogen bonding and electronic mobility in emeraldine salts. J. Mol. Struct. 317 261–266 Occurrence Handle10.1016/0022-2860(93)07898-7
V. Eswaranand T. Pradeep (2002) ArticleTitleZirconia protected silver clusters through functionalised monolayers J. Mater. Chem. 12 2421–2425 Occurrence Handle10.1039/b203081k
C. Graf A. Blaaderen Particlevan (2002) ArticleTitleMetallodielectric colloidal core–shell particles for photonic applications Langmuir 18 524–534 Occurrence Handle10.1021/la011093g
M.J. Hostetler JE. Wingate CJ. Zhong JE. Harris RW. Vachet MR. Clark JD. Londono SJ. Green JJ. Stokes GD. Wignall GL. Glish MD. Porter ND. Evans R.W. Murray (1998) ArticleTitleAlkanethiolate gold cluster molecules with core diameters from 1.5 to 5.2 nm: Core and monolayer properties as a function of core size Langmuir 14 17–30 Occurrence Handle10.1021/la970588w
A. Kumar S. Mandal PR. Selvakannan R. Pasricha AB. Mandale M. Sastry (2003) ArticleTitleInvestigation into the interaction between surface-bound alkylamines and gold nanoparticles Langmuir 19 6277–6282 Occurrence Handle10.1021/la034209c
D.V. Leff L. Brandt J.R. Heath (1996) ArticleTitleSynthesis and characterization of hydrophobic, organically-soluble gold nanocrystals functionalized with primary amines Langmuir 12 4723–4730 Occurrence Handle10.1021/la960445u
G. Liu M.S. Freund (1997) ArticleTitleNew approach for the controlled cross-linking of polyaniline: Synthesis and characterization Macromolecules 30 5660–5665 Occurrence Handle10.1021/ma970469n
S. Mitra B. Nair T. Pradeep PS. Goyal R. Mukhopadhyay (2002) ArticleTitleAlkyl chain dynamics in monolayer protected clusters (MPCs): A quasielastic neutron scattering investigation J. Phys. Chem. B 106 3960–3967 Occurrence Handle10.1021/jp0144146
R. Mukhopadhyay S. Mitra I. Tsukushi S. Ikeda T. Pradeep (2003) ArticleTitleEvolution of dynamical motions in monolayer protected metal clusters Chem. Phys. 292 223–227 Occurrence Handle10.1016/S0301-0104(03)00094-6
Nair A.S., Pradeep T., I. Maclaren. (2004a). An investigation of the structure of stearate monolayer on Au@ZrO2 and Ag@ZrO2 core–shell nanoparticles. J. Mater. Chem. DOI: 10.1039/b313850j
Nair A.S., Suryanarayanan V., Tom RT., Pradeep T. (2004b). Porosity of core shell nanoparticles. J. Mater. Chem. In press
A.S. Nair RT. Tom V. Suryanarayanan T. Pradeep (2003) ArticleTitleZrO2 bubbles from core shell nanoparticles J. Mater. Chem. 13 297–300 Occurrence Handle10.1039/b210734a
A.S. Nair T. Pradeep (2003) ArticleTitleHalocarbon mineralization and catalytic destruction by metal nanoparticles Curr. Sci. 84 1560–1564
H. Nakao H. Shiigi Y. Yamamoto S. Tokonami T. Nagaoka S. Sugiyama T. Ohtani (2003) ArticleTitleHighly ordered assemblies of Au nanoparticles organized on DNA Nano Lett. 10 1391–1394 Occurrence Handle10.1021/nl034620k
H. Patel SK. Das T. Sundararajan AS. Nair B. George T. Pradeep (2003) ArticleTitleThermal conductivities of naked and monolayer protected metal nanoparticle based nanofluids: Manifestation of anomalous enhancement and chemical effects Appl. Phys. Lett. 83 2931–2933 Occurrence Handle10.1063/1.1602578
Pillalamarri S.K., Blum FD., M.F. Bertino. (2004). Surface-initiated polyaniline-coated gold nanoparticles. Abstracts of Papers, 228th ACS National Meeting, Philadelphia, PA, United States, August 22–26. 2004
T. Pradeep S. Mitra AS. Nair R. Mukhopadhyay (2004) ArticleTitleDynamics of alkyl chains in monolayer protected Au and Ag clusters and silver thiolates: A comprehensive QENS investigation J. Phys. Chem. B 108 7012–7020 Occurrence Handle10.1021/jp0369950
N. Sandhyarani T. Pradeep (2003) ArticleTitleTowards understanding structure and phase transitions of self-assembled monolayers on two- and three-dimensional surfaces: An overview of current efforts Int. Rev. Phys. Chem. 22 221–262 Occurrence Handle10.1080/0144235031000069705
P.R. Selvakannan S. Mandal S. Phadtare R. Pasricha M. Sastry (2003) ArticleTitleCapping of gold nanoparticles by the amino acid lysine renders them water-dispersible Langmuir 19 3545–3549 Occurrence Handle10.1021/la026906v
K.G. Thomas P.V. Kamat (2000) ArticleTitleMaking gold nanoparticles glow: Enhanced emission from a surface-bound fluoroprobe J. Am. Chem. Soc. 122 2655–2656 Occurrence Handle10.1021/ja9941835
K.G. Thomas J. Zajicek P.V. Kamat (2002) ArticleTitleSurface binding properties of tetraoctylammonium bromide-capped gold nanoparticles Langmuir 18 3722–3727 Occurrence Handle10.1021/la015669d
R.T. Tom AS. Nair N. Singh M. Aslam CL. Nagendra R. Philip K. Vijayamohanan T. Pradeep (2003) ArticleTitleFreely dispersible Au@TiO2, Au@ZrO2, Ag@TiO2 and AgZrO2 core-shell nano particles: One step synthesis, characterization, spectroscopy and optical limiting properties Langmuir 19 3439–3445 Occurrence Handle10.1021/la0266435
R. Wang J. Yang Z. Zheng MD. Carducci J. Jiao S. Seraphin (2001) ArticleTitleDendron-controlled nucleation and growth of gold nanoparticles Angew. Chem. 40 549–551 Occurrence Handle10.1002/1521-3773(20010202)40:3<549::AID-ANIE549>3.3.CO;2-G
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Subramaniam, C., Tom, R.T. & Pradeep, T. On the formation of protected gold nanoparticles from AuCl −4 by the reduction using aromatic amines. J Nanopart Res 7, 209–217 (2005). https://doi.org/10.1007/s11051-005-0315-0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s11051-005-0315-0