Iron-Catalyzed Growth of Vertical Graphitic Layers on the (100) Face of Single-Crystal Diamond

The transformation of diamond into graphite occurs at elevated temperatures, and by controlling this process, sp2/sp3 carbon hybrids can be created. In this work, we study the effect of a thin iron film coating on the reconstruction of a (100) diamond face. We use a synthetic single-crystal and anneal it in ultrahigh vacuum at 1150 degrees C for 15 min. The electronic state of carbon on a clean face and a coated face is immediately examined by X-ray photoelectron spectroscopy and angle-dependent near-edge X-ray absorption fine structure spectroscopy. Raman spectroscopy and scanning electron microscopy measurements complete the structural characterization of the annealed sample. An analysis of the experimental data reveals the formation of thin sp2-carbon fragments on a clean (100) diamond surface and ordered graphite planes on the iron-coated surface. According to our estimates, iron catalyzes the transformation of roughly 10 nm diamond into graphitic layers growing vertically relative to the (100) face of the diamond.

Automated summary

By controlling the transformation process of diamond into graphite at elevated temperatures, sp2/sp3 carbon hybrids can be created. This study examines the effect of a thin iron film coating on the reconstruction of a (100) diamond face. Various spectroscopic and microscopy techniques were used to analyze the electronic and structural changes on the diamond surface. The results show the formation of thin sp2-carbon fragments on the clean diamond surface and ordered graphite planes on the iron-coated surface. Iron catalyzes the transformation of diamond into graphitic layers growing vertically relative to the (100) face.