Zhejiang University material. Dr. Haojie Yu.
University of Missouri - St. Louis SEM. Professor Dan Zhou.
The photos range over 2000x, absolutely stunning. Over two hours of hard work on a scanning electron microscope reduced to a short story that tells the full story easily.
Note in one of the 1 micron shots there is a cube near the middle. This may be CaCO3. On top of it is an agglomerated pile of carbon black nanoparticles. There are several of these agglomerated piles around the series.