3 research outputs found
Facet-Dependent Temporal and Spatial Changes in Boron-Doped Diamond Film Electrodes due to Anodic Corrosion
The progression of
corrosion in polycrystalline boron-doped diamond
(BDD) thin film electrode is explored as the electrode undergoes high-current
density anodic treatments with organic compounds. Micro-Raman spectroscopy
and spectral mapping indicate that anodic corrosion is initiated by
the conversion of sp<sup>3</sup> diamond to amorphous sp<sup>2</sup> carbon at the surface, which are then removed after longer anodic
treatment. Polarized Raman analysis reveals that corrosion-induced
changes on the surface are specific to (100)-grain facets and (111)-grain
edges. X-ray photoelectron spectroscopic measurements suggest that
carbonyl groups consequently form on these specific sites and act
as an intermediate toward the etching of the surface. This process
exposes and subsequently removes the subsurface boron atoms, thus
reducing the doping density. The observed crystal grain orientation
dependence of the corrosion process provides new insights toward a
better understanding of degradation in BDD electrodes