Chemical and microwave-assist functionalization of graphene oxide with rigid rod-like poly(phenylene ethynylene)s. Photophysical, molecular and structural analysis
In the present work, the influence of functional group incorporation on the GO surface was studied. Several approaches were applied with the aim to increase GO layers spacing and functionalize them for further application. Polymer grafting was performed via esterification reaction between the carbox...
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| Tipo de recurso: | tesis doctoral |
| Estado: | Versión publicada |
| Fecha de publicación: | 2018 |
| País: | México |
| Institución: | Centro de Investigación en Química Aplicada |
| Repositorio: | Repositorio Institucional CIQA |
| OAI Identifier: | oai:ciqa.repositorioinstitucional.mx:1025/561 |
| Acceso en línea: | http://ciqa.repositorioinstitucional.mx/jspui/handle/1025/561 |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/Doctorado en tecnología de polímeros/Doctorado en tecnología de polímeros info:eu-repo/classification/cti/2 info:eu-repo/classification/cti/23 |
| Sumario: | In the present work, the influence of functional group incorporation on the GO surface was studied. Several approaches were applied with the aim to increase GO layers spacing and functionalize them for further application. Polymer grafting was performed via esterification reaction between the carboxylic group of GO and the OH terminal group of the polymer. Nanohybrid materials comprising graphene oxide and a series of conjugated copolymers with different electron-donating and withdrawing groups were synthesized by microwave irradiation, which represents a green, effective and rapid heating method. The microwave irradiation matches perfectly with graphene oxide structure decorated with high polar functional groups which allowed the esterification. Polymers, as well as composites, were characterized by optical spectroscopy, Raman spectroscopy, cyclic voltammetry (CV), X-rays diffraction (XRD), X-Ray photoemission spectroscopy (XPS) and transmission electron microscopy (TEM). Effective interactions among the polymer functional group and graphene oxide, likely due to π–π stacking, are confirmed by fluorescence quantum yield (Φ), radiative rate constant (kr), fluorescence lifetime (τ), and non-radiative rate (k nr)constants. The introduction of graphene oxide allows for the reduction of the band gap of the active layer in optoelectronic devices. These results were corroborated by CV and UVVis spectroscopy. Graphene oxide exhibits a strong quenching effect revealed by fluorescence spectroscopy and time resolved spectroscopy. All spectroscopy data underscore the electronic coupling between polymers and graphene oxide in the nanohybrids. |
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