Photoluminescent Carbon Nanodots Integrated Polymeric Materials in One Step from Molecular Precursors

The photoluminescence (PL) origin conundrum of the carbon nanodots (CNDs) is often restrained by the disconnect between the structural complexity of the CNDs in solid-state versus the PL properties in the dispersed solution phase. Herein, the solid-state photoluminescent polymeric materials synthesized by direct polyesterification of citric acid (CA) and glycols at 180 °C and 40 h. Characteristics of these polymeric materials were compared with the carbon nanodots (CNDs) prepared from direct pyrolysis of CA at similar conditions. The polymeric materials prepared with an excess of CA possess a higher yield of CA decomposition products such as molecular acids that are trapped in the polymer matrix, therefore, observe district structural and photophysical properties from the CNDs dispersed in solution. By comparing the structural and photophysical properties of the dispersed CNDs in dioxane, with those polymeric materials prepared by a single pot from CA and glycols, it is proposed that the intermediate molecular fluorophores can be trapped along with CNDs in the polymer matrix.