Fig. 4: Kinetic investigation of single-molecule photoreactions.

a Normalized counting of survived BDP molecule collected from 45 individual single-molecule measurements as a function of irradiation time. It reveals photobleaching kinetics of the single-molecule reaction of BDP at the surface of NaYbF4:Tb(40 mol%)@NaTbF4 upconversion nanoparticles. b Plots of normalized counting of survived BDP molecule versus irradiation time indicating the single-molecule reaction of BDP accelerates after exposure to a different amount of H2O2.