Cu(OH)2 nanoneedle and nanotube arrays were electrochemically synthesized by anodization of a copper foil in an aqueous solution of KOH. The nanoneedles and nanotubes were constructed from nanosheets of Cu(OH)2. Controlling the electrochemical conditions can qualitatively modulate the lengths, amounts, and shapes of Cu(OH)2 nanostructures. The composition of as-prepared Cu(OH)2 nanostructures has been confirmed by X-ray diffraction and select-area electron diffraction. The influences of the KOH concentration of the aqueous electrolyte, the reaction temperature, and current density on the morphology of Cu(OH)2 nanostructures were investigated, and the formation mechanism of the nanostructures is discussed. Furthermore, Cu(OH)2 nanoneedles can be successfully transformed to CuO nanoneedles with little morphology change by heating. This work developed a simple, clean, and effective route for fabrication of large area Cu(OH)2 or CuO nanostructured films.

Polymeric metal complexes are constructed by combining living polymerization techniques with coordination chemistry. These metal-centered linear and star-shaped materials combine the filmforming properties of polymers with optical and other features of metal complexes. A metal template approach described herein offers a versatile alternative to the metalloinitiator method previously employed to generate Ru tris(bipyridine)-centered polystyrenes. Specifically, 4,4′-bis(chloromethyl)-2,2′-bipyridine and 4-chloromethyl-2,2′-bipyridine were utilized as initiators for both the bulk and solution polymerization of styrene using atom transfer radical polymerization (ATRP). Narrow dispersity polystyrenes with bipyridine (bpy) binding sites at the end (bpyPS) or center (bpyPS 2) of the chains result. These bpyPSn macroligands were chelated to Ru precursor complexes, RuL2Cl2 (L ) bpy, phen) or Ru(DMSO)4Cl2, to form complexes with one or three bpyPSn macroligands, respectively. Linear polymers, [RuL2(bpyPSn)] 2+ , with Ru chromophores at the end or center of the chains, as well as Ru-centered star-shaped polymers, [Ru(bpyPSn)3] 2+ , with three and six arms were produced. In all cases, dehalogenation with AgPF6 was crucial for efficient macroligand chelation. The relative efficiency of these reactions was estimated by UV/vis spectroscopy. Molecular weight determination by GPC was coupled with in-line diode array UV/ vis spectroscopy to confirm the presence of the Ru chromophores in the eluting polymer fractions. The convergent macroligand chelation approach to star-shaped polymeric metal complexes typically works best for polymers of low to moderate molecular weights (<∼65K), with higher molecular weights possible for systems with a single macroligand coordinated. Specific molecular weight thresholds encountered are determined by the number of macroligands, the position of the bpy on the polystyrene chain, and the total number of arms emanating from the metal core.

The present work reports a simple and economic route for production and characterization of stable superhydrophobic surfaces from thin copper layers coated on arbitrary solid substrates. The thin copper layer was anodized in a 2 M aqueous solution of potassium hydroxide to form a thin film of copper hydroxide nanoneedles; then the film was reacted with n-dodecanethiol to form a thermally stable Cu(SC12H25)2 superhydrophobic coating. The contact angle of the modified nanoneedle surface was higher than 150 degrees , and its tilt angle was smaller than 2 degrees . Furthermore, the surface fabricated on copper foil kept its superhydrophobic property after heating at 160 degrees C in air for over 42 h. This technique has also been applied for fabrication of copper wire with superhydrophobic submicrofiber coating to mimic water strider legs. The maximal supporting force of the superhydrophobic copper column has also been investigated in comparison to real water striders.

Highly oriented ZnO nanoneedle/nanorods arrays have been fabricated by direct oxidation of zinc foil in alkaline zincate ion solution at near room temperature (20 degrees C for nanoneedles, 30 degrees C for nanorods).

The ligand derivative, 4,4‘-bis(chloromethyl)-2,2‘-bipyridine (bpy(CH2Cl)2), and Ru(II) complexes with 2, 4, or 6 pendant halomethyl groups were employed as initiators in the atom transfer radical polymerization (ATRP) of styrene to produce linear and star polymers with ligands and chromophores at discrete positions in the polymer architectures. With the metalloinitiators, [Ru(bpy) n {bpy(CH2Cl)2}3 - n ](PF6)2 (n = 0, 1, 2), styrene polymerizations were run in bulk monomer, as well as in the presence of small amounts of anisole (14% v/v vs styrene), employing either CuCl/2bpy(C13H27)2 or CuBr/1,1,4,7,10,10-hexamethyltriethylenetetraamine (HMTETA) as the ATRP catalyst. Kinetics experiments were performed to determine the level of molecular weight control that is attainable in these polymerizations. With the former catalyst and when anisole is added, reactions exhibited increased control for the metalloinitiators and ligand initiators. Since the dicationic metalloinitiators exhibited limited solubility, which correlated with poor initiation, attempts were made to improve the compatibility of metalloreagents in the nonpolar ATRP medium. Di- and tetrafunctional metalloinitiators modified with alkyl chains, [Ru{bpy(C13H27)2} n {bpy(CH2Cl)2}3 - n ](PF6)2 (n = 1, 2), displayed improved initiation and molecular weights closer to targeted values. However, attempts to improve the solubility of the homoleptic complex, [Ru{bpy(CH2Cl)2}3](PF6)2 by substituting a BAr‘4 - counterion for PF6 - did not enhance molecular weight control. The use of DMF, a more polar solvent, in place of anisole did increase solubility of the hexafunctional initiator; at low monomer conversion, polydispersities were lower in DMF vs anisole. Polymers were characterized by gel permeation chromatography (GPC) with refractive index (RI) and multiangle laser light scattering (MALLS) detection, by UV/vis spectroscopy to confirm the covalent attachment of Ru(II) chromophores to polystyrene chains, and by modulated differential scanning calorimetry (MDSC).

Although Ru(II) tris(bipyridine) complexes and related alpha-diimine analogues find wide use in chemistry, many common ligand and metal complex derivatives are difficult to synthesize. The halomethyl bpy ligands and their inert metal complexes are one such example. These compounds are desirable since they serve as useful starting materials for a variety of more elaborate derivatives. Although 4,4'-bis(halomethyl)-2,2'-bipyridine ligands readily chelate to labile metal ions, they are not compatible with the higher temperatures and polar solvents typically required to effect ligand substitution at more inert Ru centers. Alternate routes to these targets involving solvento and other substitution labile intermediates yield products, but yields are typically low due to difficulties in purification. This report describes a new route to Ru(II) halomethyl bpy complexes involving chelation of the more robust 4,4'-bis(hydroxymethyl)-2,2'-bipyridine, bpy(CH(2)OH)(2), followed by conversion to the corresponding chloromethyl species on the metal using oxalyl chloride and DMF in THF or CH(3)CN solution. This new "OH to Cl" methodology is demonstrated for Ru(II) complexes with two, four, and six functionalities with both bpy and phen ancillary ligands. Complexes of the general formula [L(n)()Ru{bpy(CH(2)X)(2)}(3)(-)(n)()](PF(6))(2) (L = bpy, phen; X = OH, Cl; n = 0-2) have been prepared in good yield and are conveniently purified by precipitation. These Ru alpha-diimine complexes have already been utilized as multifunctional metalloinitiators for controlled cationic and radical polymerizations. They promise to be valuable for bpy derivatization generally.

We report a simple method for fabricating a lotus-like micro-nanoscale binary structured surface of copper phosphate dihydrate. The copper phosphate dihydrate nanosheets were generated by galvanic cell corrosion of a copper foil with aqueous phosphorus acid solution drops and dried in an oxygen gas atmosphere, and they self-organized into a film with a lotus-like micro-nanoscale binary structured surface. The wettability of this surface can be changed from superhydrophilic to highly hydrophobic or superhydrophobic by heating or modifying it with an n-dodecanethiol monolayer.

When metals are bound to polymers, both inner and outer sphere environments may be engineered. As is illustrated by metalloproteins, macromolecular structure and electronic environment can play important roles in modulating properties, including access to and reactivity at the metal core. For example, the protective polymer shell of hemoglobin prevents iron porphyrin dimerization, whereas in other proteins, the polypeptides influence substrate specificity. 1 Analogous features have been incorporated into synthetic systems including molecularly imprinted polymers 2 and catalysts on solid supports. 3 Although the polymer matrix and metal binding sites are not entirely uniform in these cases, site isolation and architectural control have been achieved in metal-centered dendrimers via iterative methods. 4 Another approach to well-defined polymeric metal complexes 5 involves the preparation of linear polymers with tailored binding sites by controlled polymerization, 6 followed by their chelation to metal ions. 7 This metal template-assisted polymer synthesis is highly modular and allows for systematic control over molecular weight, architecture, and metal position. 8 Especially intriguing are block copolymer analogues 9 such as metal-centered heteroarm stars, which are expected to form discrete higher order assemblies with chromophores localized at the microdomain boundaries. Luminescent [Ru(bpy) 3 ] 2+ analogues are of interest as additives for photonic materials and as probes of polymer interfaces. 10 Although heteroleptic metal complexes with nonpolymeric ligands are commonplace, it was not certain that heteroarm stars would also be easily obtained by chelation. Different factors come into play when coordination chemistry is performed with polymeric ligands. Ligand field stabilization is counterbalanced by entropic losses and interchain repulsion upon convergence, the latter of which is particularly pronounced for dissimilar polymers, which often phase-separate when mixed. Moreover, solvation influences polymeric ligand conformation in a significant way.In this study, strategic manipulation of solvent polarity was used to advantage in the assembly of ruthenium tris(bipyridine)-centered polystyrene-poly(methyl methacrylate) heteroarm stars, 1 and 2 (Figure 1). Macroligands for chelation reactions were prepared by copper-catalyzed atom transfer radical polymerization 11 using bpy ligand initiators. Bipyridine end-and centerfunctionalized polystyrenes, bpyPS, 3, and bpyPS 2 , 4, were generated from 4-(chloromethyl)-2,2′-bipyridine 12 and 4,4′-bis-(chloromethyl)-2,2′-bipyridine, 13 respectively. 5c,8 Poly(methyl methacrylate) ligands, bpyPMMA, 5, and bpyPMMA 2 , 6, (Table 1) were synthesized using bromoester bpy initiators made by esterification of the appropriate hydroxymethyl bpy 14 with 2-bromoisobutyryl bromide. Ruthenium-centered heteroarm star block copolymers were prepared by chelation of two bpyPS n macroli-(1) Bertini, I., Gray, H. B., Lippard, S.