Fluorescent Nanodiamonds with Silicon-Vacancy Color Center: A Potential Cellular Biolabels

摘要

The effect of particle size as well as the nitrogen content in the feedgas on room temperature photoluminescence of nanodiamonds, discrete nanodiamond particles of averaged size 500nm, 250nm, 100nm and 6nm were dispersed on to silicon substrate and plasma treated using microwave plasma chemical vapor deposition to create silicon vacancy color centers. We observed that adding nitrogen in feedgas increased the intensity of silicon vacancy color center room temperature photoluminescence. The resulting narrowband room temperature photoluminescence is intense, and clearly observed even for weakly agglomerated sub-10 nm size diamond. This is in contrast to the well-studied nitrogen-vacancy center in diamond which has luminescence properties that are strongly dependant on particle size, with low probability for incorporation of centers in sub-10 nm crystals. We suggest the silicon-vacancy center to be a viable alternative to nitrogen vacancy defects for use as a biolabel in the clinically-relevant sub-10 nm size regime.