Zinc ion-doped carbon dots with strong yellow photoluminescence

We demonstrated a simple strategy for facile generation of high-quantum yield robust yellow photoluminescent (PL) carbon dots (CDs) doped with zinc ions. These as-synthesized CDs when synthesized using zinc ions and citric acid as the precursor via a one-pot solvothermal method produced zinc ion-doped CDs that yielded excitation-independent yellow PL emission and the highest QY reported to date of 51.2%. We also thoroughly discuss the formation mechanism of these CDs, whose high quality was attributed to the radiative recombination of electrons and holes trapped on the CD surface. We also showed the ability to find practical applications of these as-prepared CDs, such as for bifunctional photonic crystal films and for fluorescent microfibers and patterns.