A simple and green method for the production of nanostructured materials from poly(vinyl alcohol)/graphene quantum dots

Author(s)

Rodrigues, Bruno V. M. ^{[1, 2, 3]} ; Cabral, Tayna S. ^[1] ; Sgobbi, Livia F. ^[4] ; Delezuk, Jorge A. M. ^{[2, 5]} ; Pessoa, Rodrigo S. ^{[2, 3]} ; Triboni, Eduardo R. ^[6] ; de Moraes, Thaisa B. F. ^[6] ; Lobo, Anderson O. ^{[1, 2, 7, 8]}

Affiliation

^[1] Univ Vale Paraiba UNIVAP, Sao Jose Dos Campos, SP - Brazil

^[2] Univ Brasil, BR-08230030 Sao Paulo, SP - Brazil

^[3] ITA, Ctr Ciencia & Tecnol Plasmas & Mat PlasMar, BR-12228900 Sao Jose Dos Campos, SP - Brazil

^[4] Univ Fed Goias, Inst Quim, BR-74690900 Goiania, Go - Brazil

^[5] Univ Sao Paulo, Sao Carlos Inst Phys, CP 369, Sao Carlos, SP - Brazil

^[6] Univ Sao Paulo, Engn Sch Lorena, BR-12602810 Lorena, SP - Brazil

^[7] Univ Fed Piaui, Technol Ctr, PPGCM, Interdisciplinary Lab Adv Mat, BR-64049550 Teresina, PI - Brazil

^[8] MIT, Dept Chem, 77 Massachusetts Ave, 18-393, Cambridge, MA 02139 - USA

• Document type: Journal article
• Source: Materials Chemistry and Physics; v. 219, p. 242-250, NOV 1 2018.
• Web of Science Citations: 2

Abstract

Herein, a simple, low-cost and fast approach was proposed to produce fluorescent fibers from the electrospinning of poly (vinyl alcohol)/water-soluble graphene quantum dots (GQDs). Initially, the preparation of GQDs was explored via an easy bottom-up method based on the incomplete carbonization of citric acid under different times (30, 45 and 60 min). Next, fluorescent fibrous mats were prepared from the electrospinning of PVA solutions with different contents of GQDs. These materials were further characterized via several techniques, including High-Resolution Transmission Electronic Microscopy (HRTEM), UV-vis and fluorescence spectroscopies, Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The GQDs presented a strong blue photoluminescence under UV light exposure. Among the investigated carbonization times, 45 min led to GQDs with the highest fluorescence intensity (regardless the pH) and fluorescence quantum yield (10.5%). HRTEM analysis showed that this carbonization time led to GQDs with uniform and homogeneous dimensions, with an average diameter of 2.5 +/- 0.2 nm. After electrospinning, HRTEM revealed a homogeneous distribution of GQDs into the polymeric ultrathin fibers, while increasing the GQDs content in the PVA matrix led to a clear increase in the fluorescence intensity. Interestingly, as the GQDs content increased, a slight red-shift was ob served for the maximum of emission, which may be related to light re-adsorption or even as result of Foster Resonance Energy Transfer. This set of results widens the perspectives of application of this low-cost substrate in many fields, via a simple approach using a water-soluble polymer and a naturally occurring component from citrus fruits. (AU)

• FAPESP's process: 11/17877-7 - Development of new polymeric scaffolds by electrospinning technique with incorporation of vertically aligned carbon nanotubes and nanohidroxyapatite for bone tissue regeneration
• Grantee: Anderson de Oliveira Lobo
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 13/08166-5 - Interfacial chemistry: drugs, peptides and ezymes interactions with membrane models
• Grantee: Iolanda Midea Cuccovia
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 15/08523-8 - Development of a fluorescent nanosensor from the electrospinning of PVA and graphene quantum dots: application in the detection of Alzheimer's biomarkers
• Grantee: Bruno Vinícius Manzolli Rodrigues
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/13839-0 - Organic and inorganic systems for obtaining of meso and nanostructures
• Grantee: Eduardo Rezende Triboni
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/18826-3 - Sustainable nanostructured materials based on biodegradable polymers and luminescent carbon nanoparticles
• Grantee: Bruno Vinícius Manzolli Rodrigues
• Support Opportunities: Regular Research Grants