Fig. 4
From: Comparison of Silicon Nanocrystals Prepared by Two Fundamentally Different Methods
Time evolution of photoluminescence. Panel a shows initial state of PL. Electrochemically etched (black curve) and control samples (blue curve) exhibit weak PL at 550 nm while plasma-synthetized sample with 20-nm particles (red curve) exhibit no PL. Inset of panel a shows PL of 5 nm plasma-synthetized particles which are not study in this paper. Panel b shows PL after 2 weeks of treatment. PL of the control sample slightly increases; new peak at 580 nm appears in PL of the electrochemically etched SiNCs while plasma-synthetized ones exhibit no PL all the time. Panel c shows PL after 5 weeks of treatment. PL of the control sample remains constant; the peak at 580 nm strongly increases in the case of electrochemically etched SiNCs but plasma-synthetized ones exhibit constantly no PL