Porous coordination polymer thermal

Approaches to the formation of three new types of micro-porous materials that complement zeolites will be discussed. In each case, whether metal coordination polymers, metal-linked ceramic oxide clusters, or new hybrids containing both coordination and ceramic components, engineering of the Secondary Building Unit (SBU) is of critical importance. Successful examples of these approaches include the first thermally stable 3-D micro-porous coordination polymer with chemical functionalizability [Cu3(TMA)2(H20)3] , as well as a 3-D micro-porous cluster based material [V,2B18O60H8(Cd(en)(H2O) 3]". ... 

The high thermal stability of zeolites and related micro-porous solids is one of their most attractive features. Whilst it Is clear that materials with organic components cannot withstand ultra-high temperatures, quite respectable compositional stability can be achieved. Thus the [Er(TMA)] polymer mentioned above shows no weight loss in its TGA curve before 550°C. However for porous solids another key issue is that of structural stability. Many open framework coordination polymers lose their crystalline structure upon mild heating, or even evacuation, through loss of guest molecules. 

Some lanthaitide ions have also well-known catalytic properties. For instance, the Sm(II) ion is extensively used in asymmetric catalysis (lananaga et al., 2002) and cerium and praseodymium, thanks to their 111/IV valences, are used in many depollution processes ( Catalysis by Ceria and Related Materials , 2002). This second class of application seems to be very promising as far as coordination polymers are concerned. The prerequisites for these applications are clearly a high thermal stability, a porous network and a chemical availability of the lanthaitide ions. 

The thermal decomposition of Co-BDC coordination polymer H2BDC = 1,4-ben-zenedicarboxylic acid) leads to hierarchical porous CO3O43D superstructures, assembled from 2D sheets, densely composed of many uniform nanoparticles [119]. Depending on the calcination temperature, 0036 5 or CoO were obtained from [Co(ox)-2.5H20] compound [120]. 

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