A New Method of Synthesizing Black Birnessite Nanoparticles: From Brown to Black Birnessite with Nanostructures

Table 1

Surface areas of standard material (Kaolinite) and synthesized nanosized black and brown birnessites.

Sample	Surface area m^2g^−1
Kaolinite—SRM lot # 19672-18	14.9(±1)
K-MnO2 (black birnessite synthesized by the developed method)	10.6(±1)
K-MnO2 (brown birnessite synthesized by the McKenzie method)	36.2(±1)