Effect of two sonochemical procedures on achieving to different morphologies of lead(II) coordination polymer nano-structures.
Résumé
Micro and nano-structures of a lead(II) coordination polymer, [Pb2(2-Me-8-Hq)2(MeOH)2]n (1), [2-Me-8-HqH=2-methyl-8-hydroxyquinoline], were synthesized by two sonochemical methods. These new micro and nano-structures were characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. Compound 1 was structurally characterized by single-crystal X-ray diffraction and consists of primary dimeric unit of [Pb2(2-Me-8-Hq)2(MeOH)2]. Self assembly between the dimmeric units of [Pb2(2-Me-8-Hq)2(MeOH)2] from Pb-O bonds results in formation of a one-dimensional lead(II) coordination polymer. The Pb(II)-ion in compound 1 has PbO6N1 coordination sphere with a stereo-chemically 'active' electron lone pair on the metals. By a reversible solid-state structural transformation, we successfully prepared [Pb2(2-Me-8-Hq)2]n (2) by thermal desolvation of 1. Thermal stability of compound 1 was studied by thermo gravimetric and differential thermal analyses. In addition nano-structure of PbO was prepared from calcination process of compound 1 at 873 K.