Metal cation intercalation

Considerable attention has been devoted to the study of intercalation compounds of the dichalcogenides (Whittingham, 1978 Subba Rao Shafer, 1979). Intercalation compounds of dichalcogenides can be divided into three categories (a) compounds with Lewis base type molecules such as ammonia, n-alkylamines, pyridines etc. (b) compounds with metal cations or molecular cations, Li, Na, K, etc., or [(C5H5)2Co]" and (c) compounds containing both cations and neutral polar (solvated) molecules in the van der Waals gap. 

Intercalation electrodes may include either carbon electrodes or transition metal oxide and sulfide electrodes, which intercalate with solution components such as metal cations. The most important example is intercalation of lithium ions with many types of carbonaceous materials at low potentials (0-1.5 V versus Li/Li+)... 

Bentonite, whose main ingredient is montmorillonite, is one kind of layer structure clay mineral. It is an ideal material for preparation of pillared clays. If metal cations with high catalytic activity were intercalated in the interlayers of montmorillonite, a new type of solid acid catalyst can be obtained. The catalytic activity of the catalyst is closely associated with its porosity, specific surface area and surface total acidity. One of the effective ways to enhance catalytic activity is to prepare catalyst with appropriate metal cations and structure. 

Compounds Containing Perovsldte Layers. A second class of layered oxides have structures related to the three-dimensional perovsldte lattice and include the Auriv-iUius phases, the Ruddlesden Popper phases and the Dion-Jacobson phases. The general composition can be written M [A iB 03 +i] where A is an alkaline or rare earth metal, and B is niobium or titanium. In the AurivUhus phases M = Bi202 +, whereas M is an aUcah metal cation in the ion-exchangeable Ruddlesden Popper a = 2) and Dion-Jacobson a = 1) phases. The relationships between the three structure types is shown in Figure 14. The intercalation chemistry of the Dion Jacobson phases was the first to be studied. 

Some attempts have been made to use a cationic metal complex intercalate as a catalyst these efforts are briefly reviewed in an account of the catalyst type (b) in Fig. 1. The results advocate the possibility of the immobilization of catalyst solution in the interlayer spaces. The catalytic activity of Cu -TSM or Cu Pd -TSM swelled with water or an organic solvent for the reaction involving molecular oxygen is introduced in the following section. 

There are two theories developed to explain the processes for charge storage in MnC>2.197 One theory suggests that proton (H+) and alkali metal cations (C+), present in the electrolyte, can be reversibly intercalated into the bulk of Mn02 through a reduction reaction and deintercalated via an oxidation reaction 198... 

A different phenomenon involving metallic cation/surface interactions is photointercalation (Ang and SammeUs, 1982 Rauh, 1982 Betz, 1985 Sharon et al, 1991). For lamellar semicondnctors nnder illumination, small cations can intercalate... 

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