  Understanding and engineering the domain boundaries in chemically vapor
deposited (CVD) monolayer graphene will be critical for improving its
properties. In this study, a combination of transmission electron microscopy
(TEM) techniques including selected area electron diffraction (SAED), high
resolution transmission electron microscopy (HRTEM), and dark field (DF) TEM
was used to study the boundary orientation angle distribution and the nature of
the carbon bonds at the domain boundaries. This report provides an important
first step towards a fundamental understanding of these domain boundaries. The
results show that, for the graphene grown in this study, the 46 measured
misorientation angles are all between 11-30 degrees (with the exception of one
at 7 degrees). HRTEM images show the presence of adsorbates in almost all of
the boundary areas. When a boundary was imaged, defects were seen (dangling
bonds) at the boundaries that likely contribute to adsorbates binding at these
boundaries. DFTEM images also showed the presence of a 'twin like' boundary.
