ATiNbO (A = H, Li and K) family: ionic exchange, physical and electrochemical properties.

A new layered titanoniobate, LiTiNbO, a member of the AMO family, has been synthesized using a molten salt reaction between HTiNbO and an eutectic mixture of LiOH and LiNO. This compound crystallizes in the 2/ space group with = 9.273(15) Å, = 3.788(6) Å, = 8.871(3) Å, and = 114.33(1)°, as determined by 3D electron diffraction single crystal analysis. It exhibits [TiNbO] layers similar to KTiNbO, but differs from the latter by a 'parallel configuration' of its [TiNbO] ribbons between the two successive layers. The topotactic character of the reaction suggests that exfoliation plays a prominent role in the synthesis of this new form. This new phase intercalates reversibly 2 lithium through a first-order transformation leading to a capacity of 100 mA h g at a potential of 1.67 V . Li/Li.