Control of Electron Pathway in in-situ Synthesized Carbon Dot@Cellulose Nanofiber with Stable Solid-state Emission

In this study, carbon dot (CD) was in-situ synthesized on cellulose nanofiber (CNF) surface by simple one-step hydrothermal carbonization. Based on the analyses of chemical structure and photoluminescence characteristics, we changed the electron pathway of carbon dot by controlling the CNF concentration in the composite. The electronic stabilization of CNF was observed in the composites from low CNF concentrations. Meanwhile, with high CNF concentrations, electrons were barely transferred to CNFs but recombined radiatively. Aggregation-induced blue-shifted emission occurred in the solid-state composite films without significant changes in the electron relaxation pathways. This study provides valuable insights into the electron relaxation pathway of the fabricated composite, which may be helpful in the design and economical fabrication of CD-based advanced optical devices.