DES-Engineered Bioinspired Wood Scaffolds with Fluorescence and Thermal Storage

Carbon-based quantum dots (CQDs) demonstrate quantum-enhanced photothermal conversion through bandgap-engineered light absorption, enabling efficient energy harvesting in phase change composites. This study proposes a method for delignin and functionalizing carbon dots with DES where delignified basswood-derived cellulose scaffolds provide anisotropic thermal transport channels, while polyethylene glycol (PEG) matrices functionalized with CQDs establish photon-electron-thermal coupling pathways. The engineered composite achieves congruent phase transition thermodynamics at 59.5 °C with latent heat storage capacity (163.2 J/g) comparable to pure PEG. The composite demonstrates exceptional thermoresponsive sensitivity (0.98%/°C, R2 = 0.977) with 40% fluorescence attenuation at 70 °C, suggesting CQDs’ surface defect states as effective thermal probes through temperature-modulated electron–hole pair recombination kinetics. These fundamental insights establish structure–property relationships for next-generation phase change materials with integrated energy storage and optical sensing functionalities.