title: Influence of Inert and Oxidizing Atmospheres on the Physical and Optical Properties of Luminescent Carbon Dots Prepared through Pyrolysis of a Model Molecule.
abstract: This work used L-tartaric acid as a model molecule to evaluate how the use of inert and oxidizing atmospheres during pyrolysis affected the physical and optical properties of the resulting carbon dots (CDs). Pyrolysis revealed to be a simple procedure that afforded CDs in a single step, dismissed the addition of organic solvents, and involved only one extraction stage that employed water. By X-ray diffraction a dependency between the structure of the CDs and the atmosphere (oxidizing or inert) used during the pyrolysis was found. Potentiometric titration demonstrated that the CDs were largely soluble in water; it also aided characterization of the various groups that contained sp(3) -hybridized carbon atoms on the surface of the dots. Raman spectroscopy suggested that different amounts of sp(2)- and sp(3)-hybridized carbon atoms emerged on the CDs depending on the pyrolysis atmosphere. In conclusion, the pyrolysis atmosphere influenced the physical properties, such as the composition and the final structure.
authors: Grupo de Pesquisa em Química de Materiais, GPQM, DCNat-Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, UFSJ, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP, 36301-160, São João del-Rei, MG, Brazil.
authors: Cláudia Emanuele
authors: CE
authors: Machado
authors: Grupo de Pesquisa em Química de Materiais, GPQM, DCNat-Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, UFSJ, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP, 36301-160, São João del-Rei, MG, Brazil.
authors: Letícia Gazola
authors: LG
authors: Tartuci
authors: Grupo de Pesquisa em Química de Materiais, GPQM, DCNat-Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, UFSJ, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP, 36301-160, São João del-Rei, MG, Brazil.
authors: Honória
authors: H
authors: de Fátima Gorgulho
authors: Núcleo de Espectroscopia e Estrutura Molecular, Departamento de Química, Universidade Federal de Juiz de Fora, CEP, 36036-330, Juiz de Fora, MG, Brazil.
authors: Luiz Fernando Cappa
authors: LF
authors: de Oliveira
authors: Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, CEP, 13083-970, Campinas, SP, Brazil.
authors: Jefferson
authors: J
authors: Bettini
authors: Grupo de Pesquisa em Química de Materiais, GPQM, DCNat-Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, UFSJ, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP, 36301-160, São João del-Rei, MG, Brazil.
authors: Daniela
authors: D
authors: Pereira dos Santos
authors: Grupo de Pesquisa em Química de Materiais, GPQM, DCNat-Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, UFSJ, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP, 36301-160, São João del-Rei, MG, Brazil.
authors: Jefferson Luis
authors: JL
authors: Ferrari
authors: Grupo de Pesquisa em Química de Materiais, GPQM, DCNat-Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, UFSJ, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP, 36301-160, São João del-Rei, MG, Brazil. schiavon@ufsj.edu.br.
authors: Marco Antônio
authors: MA
authors: Schiavon
keywords: atmospheres; carbon dots; luminescence; nanoparticles; optical properties; physical properties