Abstract:
Solids containing voids or empty spaces in their lattices which can be used for
trapping gas or other molecules are called porous solids. The voids or empty spaces in
these solids are occupied by guest or template molecules (usually solvent used in the
synthesis) and can be removed by simple heating or evacuation. Zeolites and porous
carbons are regarded as classical porous solids whose synthesis and properties have seen
an enormous exploration (Figure 1). Recently, coordination compounds with infinite
structures, commonly known as coordination polymers have gained enormous interest
over the classical solids. A coordination polymer is an inorganic or an inorganic-organic
polymeric structure containing metal ions/clusters linked by ligands (inorganic or
organic) with an extended structure. In the first extended network compounds, the
inorganic part contained either isolated polyhedra or small clusters. However, very soon,
it was realized that these solids could possess inorganic part with larger dimensionality,
giving rise to 1D chains, 2D sheets and 3D frameworks. The more general terms ‘MetalOrganic Framework’ (MOF) or ‘Porous Coordination Polymer’ (PCP) have later been
coined and are widely accepted in the scientific community. MOFs or PCPs are
crystalline compounds consisting of metal ions/clusters linked to organic bridging ligands
to form one (1D), two (2D), three-dimensional (3D) structures that can be porous.
