The extended time evolution size decrease of gold nanoparticles formed by the Turkevich method

Uppal, Madeeha A.; Kafizas, Andreas; Lim, Teck Hock; Parkin, Ivan P.

doi:10.1039/b9nj00745h

Cited by 38 publications

(39 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Figure 4a presents chromatograms obtained for the freshly prepared Au/Pd core/shell NPs and those that had undergone thermal treatment for 4 and 12 h (sample B, fabricated as described in the ''Experimental'' section). Upon increasing the storage time, the intensity of the signal for the Au/Pd core/shell NPs decreased, the peak width broadened slightly, and the retention time decreased, presumably as a result of Ostwald-type growth (aggregation) [27] that increased the sizes of the Au/Pd core/shell NPs during thermal treatment. The results are consistent with those from a previous study reported by Cha et al [30], who revealed a more-rapid growth rate for Pd NPs upon increasing the temperature.…”

Section: Separation Of Np Standards Using Secmentioning

confidence: 95%

“…Figure 3a displays chromatograms obtained from the freshly prepared and 4-and 12-h thermally treated Au NPs (sample A, fabricated as described in the ''Experimental'' section). The intensity of the signal for the Au NPs decreased and the retention time elongated slightly upon increasing the heating time-presumably as a result of ripening digesting, which decreases the size of Au NPs [27].…”

Section: Separation Of Np Standards Using Secmentioning

confidence: 98%

See 1 more Smart Citation

Using Size-Exclusion Chromatography to Evaluate Changes in the Sizes of Au and Au/Pd Core/Shell Nanoparticles Under Thermal Treatment

Liu

Chang

2011

Chromatographia

View full text Add to dashboard Cite

In this study, we used size-exclusion chromatography (SEC) to evaluate the sizes of Au and Au/Pd core/shell nanoparticles (NPs) that had been subjected to thermal treatment, with the eluted NPs monitored through diode array detection (DAD) of the surface plasmon (SP) absorption of the NPs. In the absence of an adequate stabilizer, thermal treatment resulted in longer retention times for the Au NPs and shorter retention times for the Au/Pd core/shell NPs in the SEC chromatograms. Thus, thermal treatment influenced the sizes of these Au and Au/Pd core/shell NPs, through digestive ripening and Ostwald-type growth, respectively. In addition, the trends in the SP absorption phenomena of the NPs in the eluted samples, as measured using DAD, were consistent with the trends of their size variations, as measured from their elution profiles. In the presence of 3A-amino-3A-deoxy-(2AS,3AS)-b-cyclodextrin (H 2 N-b-CD) as a stabilizer, the retention times and SP absorptions of the eluted Au and Au/Pd NP samples remained constant. Thus, H 2 N-b-CD is a good stabilizer against size variation duration the thermal treatment of Au and Au/Pd core/shell NPs. A good correlation existed between the sizes obtained using SEC and those provided by transmission electron microscopy. Therefore, this SEC strategy is an effective means of further searching for suitable stabilizers for NPs, especially those exposed to harsh reaction conditions (e.g., in catalytic reactions).

show abstract

Section: Separation Of Np Standards Using Secmentioning

confidence: 95%

Section: Separation Of Np Standards Using Secmentioning

confidence: 98%

Using Size-Exclusion Chromatography to Evaluate Changes in the Sizes of Au and Au/Pd Core/Shell Nanoparticles Under Thermal Treatment

Liu

Chang

2011

Chromatographia

View full text Add to dashboard Cite

show abstract

“…4−6,9,13−17 Most often, it leads to spherical NPs, but not always. 18 Essentially, DR is a thermochemical step that follows the SMAD, 4,5 the Turkevich 3 or the reverse micelle synthesis 11,19,20 in which a ligandexchange reaction induces the redistribution of atoms from polydisperse NPs and leads to a much narrower size distribution; typically with smaller average size, although the opposite has also been observed. 6,21 The term DR introduced by Klablunde and co-workers 10 is often associated with heating the as-prepared, polydisperse colloidal solution in the presence of excess strong capping ligand at or near the boiling point of the solvent under reflux.…”

Section: ■ Introductionmentioning

confidence: 99%

Understanding Digestive Ripening of Ligand-Stabilized, Charged Metal Nanoparticles

Manzanares

Peljo

2017

J. Phys. Chem. C

View full text Add to dashboard Cite

Most syntheses of thiolate-protected metal nanoparticles (NPs) include a thermochemical step in which the as-prepared, polydisperse NPs are transformed to a narrower size distribution in a poorly understood process known as digestive ripening (DR). Previous theoretical approaches considered either surface and electrostatic contributions or surface and ligand-binding contributions. We show that the three contributions are needed to obtain theoretical predictions in agreement with experimental observations. Although statistical thermodynamics does not clarify mechanistic details, it certainly provides valuable insights on the DR process. Remarkably, a relatively simple theory with no fitting parameters satisfactorily explains the roles of the metal:ligand ratio, the NP charge, the relative permittivity of the solvent, the ripening temperature, the binding energy, and the ligand chain length.

show abstract

“…In this case, the solution was usually stored in the dark at room temperature for several days before use. This was reported to have a beneficial effect on the AuNP quality, [104] although it was not found here.…”

Section: Analysis Of Citrate Aunps Via Optical Spectroscopymentioning

confidence: 76%

Building-block design

Ebeling

2015

Springer Theses

View full text Add to dashboard Cite

In order to study AuNPs, they first have to be synthesized. As already described in Section 1.2.3.2, "gold nanoparticles" is just the umbrella term for particles with fundamentally different properties, which in particular depend on their size and the kind of stabilization and thus directly on the synthesis method. Several liquid-chemical synthesis methods were performed and surveyed regarding the suitability of the products for the envisaged functionalization experiments and the experimental ease of implementation with the accessible equipment. In this section, the results from these experiments, the characteristic properties of the produced nanoparticles and feasible analysis methods for them are discussed. In Chapter 8 "Nanohybrids of gold particles", the functionalization reactions of the synthesized AuNPs using coupling reactions on their surface, the study of their interactions with trithiocarbonate groups, and the employment in grafting-to reactions with different classes of polymers will be presented. General remarks on AuNP synthesis strategiesBecause of the high curvature, the gold atoms on the surface of AuNPs are unsaturated and especially reactive. In order to obtain a stable colloid in a AuNP synthesis, particle aggregation must be prevented. This can be achieved in three fundamentally different ways:Electrostatic stabilization: The nanoparticles carry a (remaining) charge, so that they (or the oppositely charged ligand layers) repel each other. Gold colloids stabilized in this manner are very sensitive to salts. * The list only refers to the stability of AuNPs. In order to form a colloidal solution, also a good solubility is required, which is a different matter concerning the interactions with the solvent.

show abstract

The extended time evolution size decrease of gold nanoparticles formed by the Turkevich method

Cited by 38 publications

References 43 publications

Using Size-Exclusion Chromatography to Evaluate Changes in the Sizes of Au and Au/Pd Core/Shell Nanoparticles Under Thermal Treatment

Using Size-Exclusion Chromatography to Evaluate Changes in the Sizes of Au and Au/Pd Core/Shell Nanoparticles Under Thermal Treatment

Understanding Digestive Ripening of Ligand-Stabilized, Charged Metal Nanoparticles

Building-block design

Contact Info

Product

Resources

About