Figure 2: Structure of Na0.44[Mn1-xTix]O2.
From: Ti-substituted tunnel-type Na0.44MnO2 oxide as a negative electrode for aqueous sodium-ion batteries
(a) XRD patterns of Na0.44[Mn1-xTix]O2 compounds prepared at 950 °C, arranged in order of increasing titanium content from bottom to top. The bottom pattern is that of Na0.44MnO2. (b) The Rietveld plot (λ=0.7785 Å) for refined Na0.44[Mn0.78Ti0.22]O2 synchrotron XRD pattern with experimental data in black dots, calculated curve in red and difference curve in olive. (c) The Rietveld plot (λ=0.7785 Å) for refined Na0.44[Mn0.66Ti0.34]O2 pattern with experimental data in black dots, calculated curve in red and difference curve in olive. (d) General view of the crystal structure and view along c-axis showing sites for Mn ions and Ti ions located in MnO6/TiO6 octahedral/square pyramid. The cyan octahedral represents TiO6, whereas purple one represents MnO6/MnO5 polyhedron.
