Triphenylphosphine modified graphene quantum dots: spectral modulation for full spectrum of visible light with high quantum yield

We report triphenylphosphine (P(Ph)(3)) modified graphene quantum dots (P-GQDs) with high quantum yield (c) and excellent stability. The light energy absorbed by P(Ph)(3) groups can quickly and efficiently transfer to the GQDs through the C-P-(Ph)(3) bonds, resulting in a high phi. The obtained P-GQDs have a tunable photoluminescence wavelength from blue to red, and at the same time maintain a high phi, over 58%, with increase of permittivity of the solvents. The main mechanism of full-visible-light-spectrum modulation could be due to the energy loss and electron-donating decrease caused by P(Ph)(3) group-solvent interaction or relaxation.