  Scanning transmission electron microscopy (STEM) is the most widespread
adopted tool for atomic scale characterization of two-dimensional (2D)
materials. Many 2D materials remain susceptible to electron beam damage,
despite the standardized practice to reduce the beam energy from 200 keV to 80
or 60 keV. Although, all elements present can be detected by atomic
electrostatic potential imaging using integrated differential phase contrast
(iDPC) STEM or electron ptychography, capturing dynamics with atomic resolution
and enhanced sensitivity has remained a challenge. Here, by using iDPC-STEM, we
capture defect dynamics in 2D WS$_2$ by atomic electrostatic potential imaging
with a beam energy of only 30 keV. The direct imaging of atomic electrostatic
potentials with high framerate reveals the presence and motion of single atoms
near defects and edges in WS$_2$ that are otherwise invisible with conventional
annular dark-field STEM or cannot be captured sufficiently fast by electron
ptychography.
