Gold nanoparticles modification with liquid crystalline polybenzylic dendrons via 1,3-Dipolar cycloaddition

Ulloa, José Antonio ; Barberá, Joaquín (Universidad de Zaragoza) ; Serrano, José Luis (Universidad de Zaragoza)

Resumen: A series of six polybenzylic dendrons with an alkynyl focal point were synthesized for their incorporation to gold nanoparticles. Five of these compounds showed columnar mesomorphism in a wide range of temperatures. These dendrons were reacted with gold nanoparticles stabilized with a combination of a dodecanethiol and 11-azidoundecane-1-thiol. The azido group of the last compound allowed the functionalization of the nanoparticles with the six polybenzylic dendrons by 1,3-dipolar cycloaddition between their alkynyl groups and the terminal azido groups of the thiols. A high efficiency of the cycloaddition process (47–69%) was confirmed by several experimental techniques and no decomposition or aggregation phenomena were detected in the dendron-coated nanoparticles. The involved mechanism and the resulting percentage composition of the final materials are discussed. The results of the ulterior growth of the nanoparticles by thermal treatment are influenced by the size and the shape of the dendron and the temperature of the process. The structures of the final nanoparticles were investigated by TEM, DSC, TGA, NMR and UV-Vis spectroscopy. These nanoparticles do not show liquid crystal properties. However, a melting process between a crystalline and a fluid phase is observed. In the solid phase, the nanomaterials prepared show a short-range interaction between nanoparticles with a 2D local hexagonal order. A near-field effect was observed in the UV-vis spectra by coupling of different surface plasmon resonance bands (SPR) probably due to the short-range interactions. The main novelty of this work lies in the scarcity of previous studies of gold nanoparticles coated with dendrons forming themselves columnar mesophases. Most of the studies reported in the literature deal with gold nanoparticles coated with calamitic mesogens. Additionally, the effect of the thermal treatment, which in a previous paper was shown to increase the mean size of the nanoparticles without increasing their size polydispersity, has been studied in these materials.

Idioma: Inglés

DOI: 10.3390/nano12224026

Año: 2022

Publicado en: Nanomaterials 12, 22 (2022), 4026 [17 pp.]
ISSN: 2079-4991

Factor impacto JCR: 5.3 (2022)

Categ. JCR: PHYSICS, APPLIED rank: 39 / 160 = 0.244 (2022) - Q1 - T1
Categ. JCR: NANOSCIENCE & NANOTECHNOLOGY rank: 51 / 107 = 0.477 (2022) - Q2 - T2
Categ. JCR: CHEMISTRY, MULTIDISCIPLINARY rank: 58 / 178 = 0.326 (2022) - Q2 - T1
Categ. JCR: MATERIALS SCIENCE, MULTIDISCIPLINARY rank: 110 / 343 = 0.321 (2022) - Q2 - T1

Factor impacto CITESCORE: 7.4 - Chemical Engineering (Q1) - Materials Science (Q1)

Factor impacto SCIMAGO: 0.811 - Chemical Engineering (miscellaneous) (Q1) - Materials Science (miscellaneous) (Q2)

Financiación: info:eu-repo/grantAgreement/ES/DGA-FSE/E47-20R
Financiación: info:eu-repo/grantAgreement/ES/MINECO-FEDER/PGC2018-097583-B-I00
Financiación: info:eu-repo/grantAgreement/ES/MINECO-FEDER/PID2021-122882NB-I00

Tipo y forma: Article (Published version)

Área (Departamento): Área Química Orgánica (Dpto. Química Orgánica)