Abstract
Tip-induced oxidation of silicene nano-ribbonsMohamed Rachid Tchalala,*aHanna Enriquez,aAzzedine Bendounan,bAndrew J. Mayne,aG ́erald Dujardin,aAbdelkader Kara,cMustapha Ait Alidand Hamid Oughaddou*aeWe report on the oxidation of self-assembled silicene nanoribbonsgrown on the Ag (110) surface using scanning tunneling microscopyand high-resolution photoemission spectroscopy. The results showthat silicene nanoribbons present a strong resistance towards oxida-tion using molecular oxygen. This can be overcome by increasing theelectricfield in the STM tunnel junction above a threshold of +2.6 V toinduce oxygen dissociation and reaction. The higher reactivity of thesilicene nanoribbons towards atomic oxygen is observed as expected.The HR-PES confirm these observations: even at high exposures ofmolecular oxygen, the Si 2p core-level peaks corresponding to pristinesilicene remain dominant, reflecting a very low reactivity to molecularoxygen. Complete oxidation is obtained following exposure to highdoses of atomic oxygen; the Si 2p core level peak corresponding topristine silicene disappears.