Nanostructured and/or nanoscale lanthanide metal-organic frameworks

The research on metal-organic framework (MOF) compounds has developed rapidly, stimulated by not only their aesthetically pleasing structures but also diverse chemical and materials applications. The use of lanthanide-containing building blocks adds several features that are unique, fundamentally interesting, and practically significant to the construction of MOFs, due largely to the traits originated from the unique f-electronic configuration of these elements; these include primarily ionic metal-ligand interactions and flexible coordination geometry, line-like luminescence, and interesting magnetic properties associated with the exclusively high-spin configuration. Nanostructured Ln-MOFs featuring nanosized pores and channels offer even more attractive applications since when compared with their sub-nanosized analogs, a greater variety of guest species may be accommodated, either for storage or separation of guests of energy and environmental significance, sensing, or catalysis. On the other hand, reducing the physical size of MOFs to nanoscale imparts properties distinctly different from those of their bulk counterparts. Nanoparticles of Ln-MOFs have been shown to possess unique luminescence and magnetic properties for applications in optical and magnetic imaging as well as for drug delivery. This chapter provides an up-to-date review of the work on both nanostructured and nanoscale Ln-MOFs and ends with some personal perspectives regarding what future directions the research is heading toward.