By fluoride doping MoO3 to MoO2.8F0.2 the reversibility of lithium intercalation could be greatly increased and a sluggish intercalation step could be bypassed.
Significance and Impact
An earlier JCESR publication observed that Mg2+ intercalates more readily into MoO2.8F0.2 than MoO3. This work shows the initial intercalation step in MoO3 has a far lower diffusivity than the initial intercalation step of the fluoride doped compound. By showing a correlation between Li and Mg intercalation, we propose a method for screening Mg cathodes.
- Li+ intercalation studies were performed on both MoO3 and MoO2.8F0.2 and showed that fluoride doping greatly increased the reversibility and cycle life of the cathode.
- The mobility of the intercalating species drops drastically at 75 mAh/g in the fluoride doped oxide upon lithium intercalation, corresponding to the Mg2+ capacity of 75 mAh/g in the same material.