Intercalation of water in P2, T2 and O2 structure Az[COxNi1/3-xMn2/3]O2

The intercalation of water inter P2-Na-2/3[CoxNi1/3-xMn2/3]O-2 (x = 0, 1/6, 1/3) and T2 or O2 structure Li-2/3[CoxNi1/3-xMn2/3]O-2 (x = 0, 1/6, 1/3) has been investigated by X-ray diffraction and thermogravimetric analysis (TGA), Water san be intercalated into P2-Na-2/3[CoxNi1/3-xMn2/3]O-2 (x = 1/6, 1/3) but not within P2-Na-2/3[Ni1/3Mn2/3]O-2. This difference may be related to the existence of superlattice ordering of Ni atoms but not Co atoms within the transition metal layer which apparently induces a very strong interlayer interaction and inhibits the uptake of water, Two water-containing phases of P3-Na-2/3(H2O)(y)[Co1/3Mn2/3]O-2 were found and one. with y approximate to 2/3, could be prepared in pure form, By Rietveld refinement of the X-ray diffraction pattern of P2-Na-2/3(H2O)(2/3)[Co1/3Mn2/3]O-2, it can be concluded that the compound still exists in the ideal P2 structure (P6(3)/mmc) with the oxygen atoms of the water molecule located on the 2c site. Water cannot be intercalated into the corresponding lithiated phases, Li-2/3[CoxNi1/3-xMn2/3]O-2 for any value of x that we tested (x = 0, 1/6, 1/3).