A low temperature TiP2O7 polymorph exhibiting reversible insertion of lithium and sodium ions

A new TiP2O7 form has been prepared by low temperature synthesis, which does not exhibit the superstructure reported when TiP2O7 is prepared via a conventional ceramic route. This LT-TiP2O7 polymorph presents linear P2O7 pyrophosphate groups, connected through a pivotal oxygen which ensure the flexibility of the structure. Therefore it can reversibly take up both Li and Na ions, contrary to the high temperature polymorph that can only take up Li.