Lithium topotactic reactions

The reactions of these insertion materials, except for LiMnO, [19, 20], consist of electron and lithium-ion insertion into, or extraction from, each matrix without the destruction of its core structure this is called a topotactic reaction. A series of LiCovNi, v02 (0 < y < 1)) and... 

The ionic conductivity of transition metal oxides is due to ion conducting channels that exist in one (e.g., olivine), two (layered), or three (spinel) dimensions (Figure 36.2). In order to maintain the integritjr of these channels, lithium insertion reactions are generally desired to be topotactic, that is, the lithiated and delithiated states should be as crystallographically similar as possible. 

With a theoretical capacity of 1675 mAh g elemental sulfur has been considered as one of the most promising alternative cathode materials for high-capacity energy storage. The lithium-sulfur (Li-S) battery system uses conversion chemistry instead of the topotactic reactions [1] ... 

The second way in which an electroactive species such as lithium can be incorporated into the structure of an electrode is by a topotactic insertion reaction. In this case the guest species is relatively mobile and enters the crystal structure of the host phase so that no significant change in the structural configuration of the host lattice occurs. 

Originally, this referred specifically to layered structures that can undergo insertion of ions or molecules between the van der Waals gaps, but is now commonly used for any structure that undergoes topotactic insertion reactions. For Li-ion battery materials, it refers specifically to compounds that undergo reductive insertion of lithium ions, such as graphite (used as an anode) or LiCo02 (used as a cathode). 

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