Color-Tunable, White Light Emission from Electrospun Nanocomposite Fibers Sensitized by Graphene Quantum Dots

Photoluminescent, poly(sodium 4-styrenesulfonate) (PSS) electrospun fibers, sensitized by hydrophilic blue (b-GQDs) and green (g-GQDs) emitting graphene quantum dots, are demonstrated. A comprehensive experimental parametric study was conducted to determine the optimal PSS:b-GQD:g-GQD ratio and electrospinning conditions for producing nanocomposite fibers with color-tunable luminescence, including white light emission. Moreover, post-treatment of the produced fibrous materials was performed using toluene to optimize the materials’ morphological characteristics that consequently influence their optical characteristics. Based on the obtained CIE coordinates, the most promising systems in terms of pure white light emission were found to be the b-GQDs(1):g-GQDs(5):PSS system fabricated using GQDs concentration of 12 mg/mL (dual-component/g-b GQDs) with fluorescence CIE coordinates of (0.29,0.33) and the b-GQDs(0):g-GQDs(6):PSS with GQDs concentration of 4 mg/mL (single-component/g-GQDs) with derived CIE coordinates of (0.32,0.33), both after toluene treatment. This experimental design utilizes an innovative strategy for developing white-light emissive electrospun fibers by incorporating at least one luminescent component that is driven by the tunable GQD aggregation-induced emission pathway.