Intercalation - Reactions and Materials

  • West, Keld (Project Manager)
  • Zachau-Christiansen, Birgit (Project Participant)
  • Skaarup, Steen (Project Participant)
  • Jacobsen, Torben (Project Participant)

Project Details

Description

Intercalation is the reversible insertion of mobile guests - ions or molecules - into an open host structure. These reactions are conducted under mild thermal conditions where rearangements of the bonds in the host structure is prevented from kinetic reasons. Intercalation reactions may thus lead to labile products that could not be prepared by conventional equilibrium reactions.
Intercalation of ions can be driven as an electrochemical process. As the density of guest ions can be very high, such reactions are the ideal basis for charge storage in secondary (rechargeable) batteries. For this purpose, we have studied and characterized lithium and sodium intercalation in large number of transition metal oxides and sulphides. The main emphasis is on the determination of variations of the voltage of intercalation electrodes with composition - and on understanding how this property depends on both structure and chemical composition of the host materials. The voltage-composition relationship is the property that determines the energy density of batteries based on intercalation materials. We have also investigated the kinetics of intercalation reactions, as well as the ability to withstand a large number of insertion-extraction (charge-discharge) cycles.
Intercalation electrodes may be useful in other applications as well. We have studied colour changes in intercalation materials following lithium or hydrogen ion intercalation. Such materials may find use in electrochromic devices (displays). Likewise, we have studied the application of intercalation materials in sensors.
Intercalation reactions are non-equilibrium reactions offering a high degree of simultaneous control of both structure and composition which will normaly not be available through conventional equilibrium synthesis. We are presently trying to exploit this possibility in the synthesis of nano-composites made up by interprenetating inorganic (ceramic) and organic (polymer) networks.
StatusActive
Effective start/end date01/10/1978 → …