Fig. 6
From: Effect of Mn2+ concentration on the growth of δ-MnO2 crystals under acidic conditions
TEM images of δ-MnO2 react with 25 mM Mn2+ at pH 2.5 about 4 d (a and b), and 7 d (c and d). The yellow dashed lines show the side-to-side assembly in image b. The yellow dashed lines show the end-to-end assembly in image d