Surface structure of a glassy carbon. Scanning tunnelling microscopy study

Abstract

Scanning tunnelling microscopy (STM) has been used to study the topographical details of the surface structure of a glassy carbon at ultra-high resolution. In addition to small, localised graphite-like domains < 50 Å× 50 Å in area, the STM images of the glassy carbon studied, taken in the constant-tunnel-current mode in air, are in general characterized by two topographical features: (i) a granular structure with grain sizes typically in the range 80.0–250.0 Å in some surface locations and (ii) straight or curved fibrillar structures lying side by side, in other surface locations. The latter are considered to reflect the residual structure of the polymer chains initially present during processing of the material.