Table 3.
Phases | Average composition | Average composition with proton balance | Mean Mn AOS | SE(hyd), J/m2* |
CR2 | K0.11·MnO1.94·0.37H2O | K0.11H0.12MnO2·0.37H2O | 3.78 ± 0.01 | 0.77 ± 0.10 |
NaBi | Na0.09·MnO1.82·0.52H2O | Na0.09·H0.36MnO2·0.52H2O | 3.56 ± 0.01 | 0.69 ± 0.13 |
KBi | K0.21·MnO1.87·0.33H2O | K0.21H0.27MnO2·0.33H2O | 3.52 ± 0.01 | 0.55 ± 0.11 |
CaBi | Ca0.12·MnO1.81·0.72H2O | Ca0.12H0.38MnO2·0.72H2O | 3.50 ± 0.01 | 0.41 ± 0.11 |
CaMnO† | Ca0.39MnO2.34·0.42H2O† | Ca0.05MnO2·0.42H2O† | 3.89 ± 0.01 | 0.75 ± 0.11 |
CaMnO† | Ca0.43MnO2.27·0.31H2O† | Ca0.16MnO2·0.31H2O† | 3.68 ± 0.01 | 0.57 ± 0.12 |
Cryptomelane: CR2, NaBi, KBi, and CaBi (Bi, birnessite) are from the present work.
Surface enthalpies are for the hydrous surfaces [SE(hyd)].
Samples of Ca–Mn–oxide nanosheets (6).