Extended Data Fig. 3: STM analysis of the air exposed k-chGNR sample before and after annealing.
From: Circumventing the stability problems of graphene nanoribbon zigzag edges
(a) Overview STM image of a ketone-GNR sample that was exposed to air for 24 minutes, without any further treatment. I = 50 pA; Vbias = 1.5 V. (b) and (c): STM images of the same sample after annealing to 200 °C for 1 hour. (b) I = 20 pA; Vbias = −0.8 V. (c) I = 30 pA; Vbias = −0.8 V. Although most have desorbed, a notable number of contaminants are still present on the surface after the annealing treatment. Islands of alkyl chain contamination from the ambient conditions are indicated in (c) with a blue arrow.
