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The synthesis of nanostructured material is importance for the step from fundamental science to potential applications. This is true for coordination polymers and (porous) coordination networks particular. They are discussed for their high potential in drug delivery, chemical sensing, catalysis, as well as contrast agents, battery electrodes or solid electrolytes. Such applications are difficult to visualize for bulk materials, but need nano-size and incorporation into composite materials or functional devices. Advantages in processing and device construction are one further motivation for the nanostructures of such materials. In other hand, the nucleation and growth are two important processes for nanocrystal formation in a liquid medium. Synthesis methods are available for the synthesis of nanostructures of coordination polymers such as controlled precipitation (solvent-induced precipitation, ultrasonic, microwave, capping ligands, modulators, etc.) micro-emulsion as micro-reactors for size control and electrostatic stabilization. Among the various synthetic routes, ultrasound-assisted method is applicable for nanoscaled coordination polymer preparation as their reaction conditions can be easily adapted from conventional approaches, and is now positioned as one of the most powerful tools. In this chapter, the focus has been more on this method and various factors have been studied on the size and morphology of the nanostructures. Finally application of nano coordination polymers in field of adsorption removal, photo-catalytic degradation, use as templates in order to obtain the desired nanomaterials, anti-cancer drugs, supercapacitors and catalytic activities has been investigated.

New 2D lead(II) coordination polymers, Pb(4-bpdh)(CH3COO)(NO3)]n (1) and [Pb(4-bpdh)(ClO4)(NO3)]n (2), 4-bpdh ​= ​2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene, were prepared and characterized by single-crystal X-ray diffraction. Compound 3 with formula [Pb(4-bpdh)(NO3)2(H2O)]n (3) was obtained by solid state mechanochemical reaction of the compounds 1 and 2 via anion-exchange process. These conversions are reversible and the grinding of compound 3 with CH3COO¯ and ClO4¯ ions led to the formation of the compounds 1 and 2, respectively. Thermal decomposition of the compounds 1–3 results in the formation of different metallic composites. The composites were characterized by X-ray powder diffraction (XRD) and size and morphology of them were investigated by scanning electron microscopy (SEM).

A new two-dimensional lead(II) coordination polymer, [Pb(Pro)2] n (1); Pro = l-proline amino acid, has been synthesized and characterized by IR and X-ray diffraction. Structural determination of compound 1 reveals the Pb(II) ion is four-coordinated, bonded to two nitrogen atoms and two oxygen atoms from the l-proline ligand. PbO nanoparticles were synthesized by calcination of compound 1 at 500, 550 and 600 °C under air atmosphere. The PbO nanostructure was characterized by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The thermal stability of compound 1 was studied by thermal gravimetric analysis (TGA) and differential thermal analysis (DTA). Increase in calcination temperature decreased particles size and also led to layer-shape nanostructures morphology.

Nanoparticles of two new coordination polymers, [Pb(5,5′-dm-2,2′-bpy)Cl2] n (1) and [Pb(5,5′-dm-2,2′-bpy)Br2] n (2), {5,5′-dm-2,2′-bpy = 5,5′-dimethyl-2,2′-bipyridine}, have been synthesized by ultrasonic assistance at different concentrations and characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. Metal oxide nanoparticles were prepared from thermal decomposition of compounds 1 and 2 at 600 °C under air atmosphere. Scanning electron microscopy images of the residue which are obtained from calcination of compounds 1, 2 show the formation of lead(II) oxide nanoparticles with an average diameter of about 80 and 90 nm for compounds 1 and 2, respectively.

Nanostructures of three Zinc(II) coordination polymers, [Zn(NNO)2(H2O)4]n (1), [Zn(PNNO)2(H2O)2]n (2) and [Zn(H2O)6]·(INNO)2 (3) {NNO: Nicotinic acid N-oxide, PNNO: Picolinic acid N-oxide and INNO: Isonicotinic acid N-oxide}, have been synthesized by a sonochemical process and reaction of ligands with Zn(CH3COO)2. The Zinc(II) oxide nano-particles have been synthesized from thermolysis of [Zn(NNO)2(H2O)4]n (1), [Zn(PNNO)2(H2O)2]n (2) and [Zn(H2O)6]·(INNO)2 (3) at two different methods (with surfactant and without surfactant) and two temperatures (200 and 600°C). The ZnO nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Comparison of the SEM images of ZnO nano-particles at two different methods and temperatures shows that higher temperature results in an increasing of agglomeration and thus small and spherical ZnO particles with good separation were produced by thermolysis of compounds at 200°C and by use of surfactant.

Four new Zn(II) and Cd(II) coordination polymers, [Zn(2-AMP)2(N3)2]n (1), [Zn(2-AMP)2(SCN)2]n (2), [Cd(2-AMP)(N3)2]n (3) and [Cd(2-AMP)2(SCN)2]n (4) {2-AMP: 2-Aminomethylpyridine}, have been synthesized and characterized by single crystal X-ray diffraction, IR spectroscopy and elemental analyses. The Zinc(II) oxide and Cadmium(II) oxide nano-particles have been synthesized from thermolysis of 1–4 at 600 °C under air atmosphere for 4 h. The ZnO and CdO nanoparticles were characterized by X-ray diffraction and scanning electron microscopy (SEM). SEM images show the average size of produced ZnO and CdO nanoparticles are 60–70 nm in all compounds.

Two typical highly porous metal-organic framework (MOF) materials based on lead(II), [Pb(4-bpdh)(NO3)2(H2O)]n (TMU-1) and [Pb(4-bpdh)(NO3)2]n (TMU-2) have been used for the removal of harmful dyes (anionic dye methyl orange (MO) and cationic dye methylene blue (MB)) from contaminated water via adsorption. The adsorption capacities of TMU-1 and TMU-2 are much higher than those of an activated carbon. Our results show that the difference between MO and MB adsorption in TMU-1 and TMU-2 could be relate to pore size and coordinated H2O interactions. Dye elimination has also been studied by the use of adsorption/desorption process. The delivery of dyes from compounds in methanol at room temperature was determined by UV/vis spectroscopy.

Two Zinc(II) coordination polymers [Zn(NO2)2(3-bapp)]n·nH2O (1) and [Zn(NO2)2(4-bapp)]n·nH2O (2) have been synthesized by using zinc acetate, sodium nitrite, {3-bapp: 2,6-bis (3-amidopyridyl) pyridine} and {4-bapp: 2,6-bis (4-amidopyridyl) pyridine} as precursor. Pure phase ZnO nano-rods were obtained by thermolyses of compound 1 and 2 in 600 °C for 3 h under air atmosphere. The ZnO nano-rods were characterized by X-ray diffraction and scanning electron microscopy. The average crystallite size of ZnO nano-rods (1), (2) were determined 30 and 40 nm respectively. The particle size of hexagonal nano-rods of (1) and (2) are in the range of 20–70 and 30–80 nm respectively. The photo-catalytic performance of degradation of Congo red solution was increased when the particles size were decreased.

Nanostructures of the three-dimensional coordination polymers with the ligand 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh), [Pb(4-bpdh)(NO3)(μ-NCS)]n (1) and [Pb(4-bpdh)(μ-NCS)2]n (2), have been synthesized by a sonochemical process at different concentrations and characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. The solid state structural transformations of nano-compounds 1, 2 by anion-replacement processes under mechanochemical reaction, have been verified by IR and PXRD measurements. The SEM images showed that morphology change occurs on nanostructures during solid state anion-replacements.

Assembly of quinoxaline with Cd(II) in the presence of SCN− anion produces a new coordination polymer [Cd(Quinoxaline)(SCN)2(CH3CN)] n [Cd(Quinoxaline)2(SCN)2] n (1) and is characterized by IR, 1H NMR and 13C NMR spectroscopy. The single-crystal X-ray data of compound 1 show that this coordination polymer grows in two-dimensional supramolecular structure. In this polymer, the organic ligand chelate through its one nitrogen atom to cadmium(II) atom and thiocyanate anion acts as a bridge to two cadmium(II) atom in the chains. Also, nanoscale of CdS has been synthesized by calcination at 400, 500 and 600 °C under air atmosphere and characterized by scanning electron microscopy, X-ray powder diffraction and energy-dispersive X-ray. The thermal stability of compound 1 was studied by thermal gravimetric and differential thermal analyses.

A three-dimensional porous coordination polymer, [Pb(4-bpdh)(NO 3 )(H 2 O)] n ( TMU-1 ), has been synthesized with reaction of lead(II) nitrate and 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh). When solid TMU-1 was immersed in the ethanol solution of AgNO 3 for 5, 15 or 60 min and 20 h at room temperature, solid including Ag nanoparticles is formed ( Ag@TMU-1 ), as evidenced by HRTEM images and EDX spectrum. The visible fluorescence study of Ag@TMU-1 is another evidence for loading of silver nanoparticles on TMU-1 . Silver oxide and silver nanoparticles supported on nanocrystalline PbO were synthesized by heating of Ag@TMU -1 in air and Ar at 600 °C, respectively. The visible fluorescence study of Ag@TMU-1 is another evidence for loading of silver nanoparticles on TMU-1 .

Three new cadmium(II) coordination complexes, namely, [Cd2(1,2-bix)4(L)4]n (1), [Cd(1,3-bix)(L)2]n·H2O (2), [Cd(1,4-bix)(L)2H2O)]n·2.5H2O (3) have been synthesized using 4-carboxybenzaldehyde (HL) and 1,n-bis(imidazol-l-ylmethyl)benzene (1,n-bix; n = 2, 3, 4) as ligands. These complexes were structurally characterized by single-crystal X-ray crystallography and further characterized by FT-IR spectroscopy and thermogravimetric analysis (TGA). Complex 1 is a binuclear, complex 2 possesses a 1D double chain. Compound 3 features a 1D zigzag chain, assembled into a 2D layer structure by weak π–π interactions. The photoluminescent properties of the compounds 1–3 were also investigated.

Supported palladium nanoparticles on Mn-carboxylate coordination polymer (Pd/MnBDC) were prepared using solution impregnation method. This new catalyst was characterized by XRD, SEM, TEM, EDX, XPS, FTIR and TGA analysis. The Pd/MnBDC exhibits efficient catalytic activity for the Mizoroki–Heck coupling reaction between iodobenzene and either aromatic or aliphatic terminal alkenes and reuses up to four runs without significant loss of activities.

A three-dimensional (3D) nanoporous coordination polymer, [Pb(4-bpdb)(μ-NO3)(μ-SCN)]n·1.5CH3OH (TMU-15), was synthesized from the reaction of Pb(II) salt and 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene (4-bpdb) in a branched tube. Compound TMU-15 is stable for loading of guests. In this compound, we successfully loaded the porous crystals with I2 by suspending them in a solution of I2 in cyclohexane. The delivery of I2 from TMU-15 was performed in ethanol, a nonaromatic solvent, at room temperature and determined by UV/vis spectroscopy. The delivery and desorption rate of iodine from TMU-15 were also compared with those from analog compounds such as [Pb(4-bpdh)(NO3)2(H2O)]n (TMU-1) and [Pb(4-bpdh)(NO3)2]n (TMU-2).

Two mercury(II) complexes [Hg(4-mtrt)Cl2] (1) and [Hg(4-mtrt)Br2] (2), have been synthesized from reaction of ligand 4-methyl-4H-1,2,4-triazole-3-thiol (4-mtrt) with HgCl2 and HgBr2. Structures of compound 1–2 have been characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction. The nanoparticles of compound 1–2 have been prepared by sonochemical method. The new nano-structures were characterized by scanning electron microscopy, elemental analysis, IR spectroscopy and X-ray diffraction (XRD). The size of the samples prepared by sonochemical method are about 50 and 60 nm in compounds 1 and 2 respectively.

Two zinc(II) complexes [Zn(6,6′-dimethyl-2,2′-bipy)Cl2]n (1) and [Zn(6,6′-dimethyl-2,2′-bipy)I2]n (2) are synthesized from the reaction of the 6,6′-dimethyl-2,2′-bipy ligand with ZnCl2 and ZnI2. Zinc(II) oxide nanoparticles are synthesized by the thermolysis of [Zn(6,6′-dimethyl-2,2′-bipy)Cl2]n (1) and [Zn(6,6′-dimethyl-2,2′-bipy)I2]n (2) at two different temperatures. The ZnO nanoparticles are characterized by X-ray diffraction and scanning electron microscopy (SEM). SEM images show the average size of the ZnO nanoparticles produced of 50 nm and 60 nm in compounds 1 and 2 respectively.

Two new nano-structured Hg(II) supramo- lecular complexes, (Hg(5,5 0 -di-t-but-bpy)(l-Br)Br)2(Hg(5, 5 0 -di-t-but-bpy)Br2)(1) and (Hg(5,5 0 -di-t-but-bpy)I2 )( 2) were synthesized by the sonochemical method. The struc- tures of 1 and 2 were characterized by elemental analysis, IR, 1 H-NMR, and 13 C-NMR spectroscopy and single crystal X-ray diffraction. Their thermal stabilities were studied by thermogravimetric and differential thermal analyses. Solid-state luminescent spectra of 1 and 2 indi- cate a fluorescent broad emission band between 304 and 404 nm with excitation at 284 nm. These nanostruc- tured coordination polymers were characterized by scan- ning electron microscopy, elemental analysis, and IR spectroscopy.

A new coordination polymer of lead(II) nitrate complexes with bridging trans-1,2-bis(4-pyridyl)ethene (bpe) ligand, [Pb(µ-NO3)2(bpe)(MeOH)]n (1), has been synthesized and characterized by elemental analysis, FT-IR, 1H, 13C-NMR, thermal analysis and single crystal X-ray diffraction. In compound 1, lead(II) ions are bridged by nitrate ligands forming linear chains, which are also further coordinated by neutral bpe and methanol ligands into a two-dimensional polymeric chain. This polymeric precursor has been used to prepare PbO nano-particles using two different method. The prepared lead(II) oxide nano-structure was characterized by scanning electron microscopy and X-ray powder diffraction.

Nano-structures of Pb(II) 2-D coordination polymers, [Pb2(µ-2-bpdbe)2(NO3)4] n (1) {2-bpdbe = 1,6-bis(2-pyridyl)-2,5-diaza-1,5-hexadiene}, were synthesized by the sonochemical method. The structure of 1 may be considered a coordination polymer of lead(II) formed by bridging 2-bpdbe ligands, making a 2-D array of Pb(NO3)2 and 2-bpdbe. The thermal stability of the material was studied by thermal gravimetric and differential thermal analyses. The new nano-structure coordination polymer was characterized by scanning electron microscopy, elemental analysis, and IR spectroscopy. The sizes of the nano-structures were approximately 50 nm. Nano-particles were obtained by thermolysis of 1 in oleic acid as a surfactant at 180°C and 200°C under air atmosphere and the size of the PbO particles were about 60 nm.

A new nano-coordination polymer of lead(II) nitrate with the ethylenediamine (en) ligand, [Pb(en)(NO3)2] n (1), has been synthesized by a sonochemical process and characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. The structure of 1 has been characterized by single crystal X-ray diffraction. In 1, Pb(II) ions are bridged by nitrate ligands forming linear chains, which are also further coordinated by neutral en ligands. This polymeric precursor has been used to prepare Pb(II)O nano-particles using two different methods. The prepared Pb(II)O nano-structure was characterized by scanning electron microscopy and X-ray powder diffraction.

A new nano-sized Zn(II) complex, [Zn(5,5′-dtbu-2,2′-bipy)Cl2] n (1) was synthesized and its structure determined by X-ray crystallography. The new nano-sized complex was prepared at oleic acid as a surfactant at 280 °C and characterized by scanning electron microscopy, elemental analyses and IR spectroscopy. The ZnO nano-particles were synthesized from thermolysis of nano-compound 1 at 600 °C and similar compound, [Zn(5,5′-dimethyl-2,2′-bipy)Cl2] n (2), at two different methods. SEM images show the average size of ZnO nano-particles are 78 and 50 nm for the compounds 1 and 2, respectively.

Two new lead(II) nitrate coordination polymers from ligand 1,2-di-(4-pyridyl)-ethylene (bpe), [Pb2(μ-bpe)3(μ-NO3)2(NO3)2]n (1) and {[Pb(μ-bpe)(μ-NO3)2(NO3)(H2O)]·(Hbpe)·0.5(bpe)}n (2), were synthesized. The compounds 1 and 2 were characterized by IR spectroscopy, elemental analyses and X-ray crystallography. The structures of 1 and 2 may be considered coordination polymers of lead(II) consisting of metallocyclic chains formed by bridging bpe ligands, making two- and one-dimensional array of Pb(NO3)2 and bpe, respectively. Pure phase PbO nano-particles were obtained by thermolyses of compounds 1–2 in oleic acid as surfactant at 180 and 200 °C under air atmosphere. The PbO nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

A reversible anion-exchange of 2D lead(II) coordination polymers with the ligand 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene (4-bpdb), from 2D [Pb(4-bpdb)Br2]n (1) to 2D [Pb(4-bpdb)Cl2]n (2) coordination polymer by solid state anion-replacement processes under mechanochemical reactions, has been studied. The reversible solid state structural transformations of compound 1 to compound 2 by anion-replacement have been verified by PXRD and IR spectroscopy. PbBr2 and PbCl2 nanoparticles were obtained by thermal decomposition of compounds 1 and 2 in oleic acid as surfactant at 180 °C under an air atmosphere. These nanoparticles were characterized by powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM).

A new nano-sized lead(II) coordination polymer, {[Pb2(μ-3-bpdh)(μ-NO3)3(NO3)]n (1); (3-bpdh = 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene)}, was synthesized by a sonochemical method. The structure of 1, which may be considered coordination polymer of lead(II), consists of metallocyclic chains formed by bridging NO3 − and 3-bpdh ligands, thereby making a 2D array of Pb(NO3)2 and 3-bpdh. The thermal stability of compound was studied by thermogravimetric and differential thermal analyses. The new nano-structure coordination polymer was characterized by powder X-ray diffraction, elemental analysis and IR spectroscopy. The scanning electron microscopy shows the particle size of the 1 prepared by the sonochemical method is about 95 nm. The PbO nanoparticles were obtained by thermolysis of 1 at 180 °C with oleic acid as a surfactant. The scanning electron microscopy shows that the size of the PbO particles are ~60 nm.

A three-dimensional (3D) porous coordination polymer, [Pb(4-bpdh)(NO3)(H2O)]n (HMTI-1), has been synthesized under microwave-irradiation (MW) of identical reaction mixtures of Pb(II) salt and 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh) at different powers. The microwave synthesis of HMTI-1 has been compared to its conventional synthesis. It has been found that by using MW synthesis HMTI-1 can be obtained in a much shorter synthesis time with improved yield and physical properties. Compound HMTI-1 is stable up to 300 °C in the static atmosphere of nitrogen and useful for loading and unloading of guests. In this compound, we successfully loaded the porous crystals and nano-HMTI-1 with I2 by suspending them in a solution of I2 in cyclohexane. The delivery of I2 from HMTI-1⊃3I2 performed in ethanol, a nonaromatic solvent, at room temperature was determined by UV/vis spectroscopy. A comparison of adsorption and desorption rates of iodide between nano and bulk compounds was also conducted.

Yilmaz, Veysel/0000-0002-2849-3332 WOS: 000339131900035 Nanostructures of the porous three-dimensional coordination polymers, [Pb(4-bpdh)(NO3)(H(2)0)](n) (HWITI-1), and [Pb(4-bpdh)(NO3)](n). (HMTI-2), {4-bpdh = 2,5-bis(4-pyridy1)-3,4-diaza-2,4-hexadiene}, have been synthesized by a sonochemical process at different concentrations and characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. Lead(11) oxide nanoparticles were prepared from thermal decomposition in oleic acid and direct calcination of compounds HIVITI-11 and H1VM-2 at different temperatures. The results of this study indicated that the size of the coordination polymer precursor and temperature correlates to the particle size of the formed lead(II) oxide nanoparticles. Also results show that a decrease in the particles size of compounds leads to a decrease in the particles size of the Pb0. In other hand decrease in size of compounds lead to increase in catalysis activity too. (C) 2014 Elsevier B.V. All rights reserved. Tarbiat Modares University Support of this investigation by Tarbiat Modares University is gratefully acknowledged.

The reversible crystal-to-crystal transformations of a 1D lead(II) coordination polymer with the ligand 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh), from [Pb(4-bpdh)Br2]n (1) to intermediate [Pb(4-bpdh)(Br)(NO3)]n (2) and [Pb(4-bpdh)(NO3)2(H2O)]n (3) by a solid state anion-replacement processes under mechanochemical reactions, have been studied. The reversible solid state structural transformation of compound 1 to compound 2 and then 3 by anion replacement have been verified by PXRD and IR measurements. PbBr2, PbBr(OH), Pb3O2Br2 and PbO nanoparticles were obtained by the thermal decomposition of compounds 1, 2 and 3 in oleic acid at 180 °C in an air atmosphere, respectively. These nanoparticles were characterized by powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM).

Reversible crystal-to-crystal transformations of 3D lead(II) coordination polymers with the ligand 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh), from nitrate analoge [Pb(4-bpdh)(NO3)2(H2O)]n (1) to [Pb(4-bpdh)(NO3)(Br)]n (2), [Pb(4-bpdh)(Br)2]n (3), [Pb(4-bpdh)(NO3)(Cl)]n (4) and [Pb(4-bpdh)(Cl)2]n (5) by solid state anion-replacement processes under mechanochemical reactions, have been studied. The reversible solid state structural transformations of compounds 1-5, by anion-replacement processes under mechanochemical reaction, have been verified by PXRD measurements. Nanoparticles of compounds were synthesized by sonochemical process and characterized by scanning electron microscopy (SEM), powder X-ray diffraction, IR spectroscopy and elemental analyses. The SEM images showed that morphology change occurs during solid state anion-replacements of nanocrystals.

A reversible crystal-to-crystal transformation of a 1D lead(II) coordination polymer to a 2D lead(II) coordination polymer with the ligand 1,2-di-(4-pyridyl)-ethylene (bpe), [Pb2(μ-bpe)3(μ-NO3)2(NO3)2(H2O)2]n (1) to [Pb2(μ-bpe)3(μ-NO3)2(NO3)2]n (2), by de- and rehydration has been observed and the structures of 1 and 2 were determined by single crystal X-ray diffraction. The thermal stabilities of compounds 1 and 2 were studied by thermal gravimetric and differential thermal analyses. Powder X-ray diffraction experiments showed that the phase transitions observed for the single crystals also occur in the batch powder samples and lead to monophasic products. Nano-particles of compound 1 were synthesized by a sonochemical process and characterized by scanning electron microscopy (SEM), powder X-ray diffraction, IR spectroscopy and elemental analyses. The SEM images showed that no change in the morphology occurs during this dynamic crystal-to-crystal conversion.

A reversible anion exchange of 1D lead(II) coordination polymers with the ligand 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh), from [Pb(4-bpdh)Cl2]n (1) to intermediate 2D [Pb(4-bpdh)(Cl)(NO3)]n (2) and then 3D porous coordination polymer [Pb(4-bpdh)(NO3)2(H2O)]n (3) by solid state anion replacement processes under mechanochemical reactions, have been studied. The reversible solid state structural transformations of compound 1 to compound 2 and then 3 by anion replacement have been verified by PXRD and IR spectroscopy. PbCl2, Pb3O2Cl2 and PbO nanoparticles were obtained by thermal decomposition of compounds 1, 2 and 3 in oleic acid as surfactant at 180 °C under an air atmosphere, respectively. These nanoparticles were characterized by powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM).

A reversible crystal to crystal transformation of a new porous 3D lead(II) coordination polymer with the ligand 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh), [Pb(4-bpdh)(NO3)2]n (HMTI-2) to [Pb(4-bpdh)(NO3)2(H2O)]n (HMTI-1), by hydration and dehydration, has been observed. Powder X-ray diffraction experiments and IR analysis showed that the compounds obtained by hydration and dehydration have same crystalline lattice. Among the proposed methods for the removal of dyes and toxic materials such as iodine from contaminated water, removal by adsorption technologies is regarded as one of the competitive methods because of high efficiency, economic feasibility and simplicity of operation. In this work, we successfully loaded compounds HMTI-2 and HMTI-1 with I2 by suspending them in a cyclohexane solution of I2. The delivery of I2 from compounds HMTI-2 and HMTI-1 in ethanol at room temperature was determined by UV-vis spectroscopy. Adsorption and desorption rate of iodide in HMTI-1 and HMTI-2 shows that present of H2O molecules have effective role in increase of iodine adsorption in HMTI-1.