abstract
The functionalization of nanographene oxide (GO) with polymers is desirable for increasing the interface compatibility of GO, thereby enabling its use in a variety of applications such as biomedical and energy storage systems. Typically, wet chemistry processes are used to achieve polymer functionalization of GO, having limitations of high heterogeneity, time consumption, and difficult purification processes. Two approaches for dry functionalization of the nano-GO surface are therefore proposed, utilizing an atomic layer deposition (ALD) reactor: (1) vaporization-condensation of polyethylene glycol amine (PEG-NH2) and (ii) molecular layer deposition (MLD) of a polymer hybrid from trimethylaluminum (TMA) and ethylene glycol (EG). Carboxylic activated nano-GO (GO-COON) powders were exposed to PEG at variable temperatures, determining that a minimum of 100 degrees C was sufficient for adsorption of the polymer. In addition, a layer by layer deposition (an MLD route) is proposed to impart control over the growth of a polymer hybrid onto the GO COOH surface and to enhance the efficiency of polymer deposition by sequentially supplying a passivation layer, -Al- bonds, for monomer attachment. FTIR and XPS results showed effective control on the growth of the hybrid polymer at the GO COOH surface, achieved through optimization of ALD reactor experimental conditions.
keywords
GRAPHENE OXIDE; POLYETHYLENE-GLYCOL; FILMS; ALUMINA; NANOSHEETS; NANOPARTICLES; PEGYLATION; THERAPY; GROWTH
subject category
Chemistry; Science & Technology - Other Topics; Materials Science
authors
Jaggernauth, A; Silva, RM; Neto, MA; Hortiguela, MJ; Goncalves, G; Singh, MK; Oliveira, FJ; Silva, RF; Vila, M
our authors
Aneeta Jaggernauth
PhD Student
Filipe José Alves de Oliveira
Principal Researcher
Miguel Ângelo da Costa Neto
Researcher
Ricardo Manuel Fonseca Lopes da Silva
Junior Researcher
Rui Ramos Ferreira e Silva
Associate Professoracknowledgements
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate cofinanced by FEDER under the PT2020 Partnership Agreement. M.K.S. acknowledges Bilateral Indo-Portuguese 2015/2017 Project, FCT 2013 Investigator Call (IF/00976/2013).