Coordination‐Polymeric Nanofibers and their Field‐Emission Properties

Abstract

The large-scale fabrication of nanofibers of coordination polymers (CPs) is reported for the first time from CP gel precursors by the electrospinning method. In the absence of organic polymeric additives, viscous solutions suitable for drawing fibers have been made by diluting the gel precursors, which are obtained by mixing Ni(OAc)(2) and 4-trifluoromethylbenzoic acid with 4,4'-bis(pyridyl)ethylene (bpe) or 4,4'-bipyridine (bpy) linear spacer ligands in organic solvents. One-dimensional polymeric structures have been proposed for these gels and nanofibers based on the crystal structures of the compounds isolated. These fibers show some interesting field-emission properties. The results described here may well be extended to other one-dimensional polymers, thus opening the door for processing of the coordination polymers.

Multi-scale crystal engineering of metal organic frameworks

“…In some cases the preparation method of the crystalline particles is not only relevant for the morphology tuning but also provides a suitable medium for their implementation on functional devices [115,290]. In fact, crystal engineering of numerous luminescent MOFs and CPs has been reported, aiming at their use in (opto)electronic applications [109,111,122,290,291].…”

“…In such way, nanospheres with average diameter of 116 nm form in the reaction mixture under static conditions, while well-defined nanorods were observed when the reaction mixture was vigorously stirred. Similarly, uniform nanofibers of [[Ni(TBA)(m-BPY)]·BPY] n (TBA = 4-trifluoromethylbenzoate; BPY = 4,4´-bipyridine) have been prepared by direct precipitation under vigorous stirring [115]. Furthermore, Liu et al [97] observed evolution of [Ce(1,3,5-BTC)(H 2 O) 6 ] n morphology from straw-sheaf, urchin-like to nanorods when 1,3,5-BTC and Ce 2+ reacted without stirring.…”

“…[(Ag-2)NO3]n fibers 9 b) [112] ZIF-8 hexagonal 40 [62] [ [122] [SnT(4-Py)PCl2]n spheres 116.7 [114] [[Ni(TBA)(m-BPY)]·BPY]n fibers 100 b) [115] [Zn(BIBP)2(OSO2CF3)2]n sheets 2-3·10 3 [123] [Ag(L1)NO3]n rods 20-30 [94] [ [100]…”

Metal-containing nanofibers via coordination chemistry

“…The intensity of the fluorescence was enhanced significantly in the gel form compared to free ligand 23 and a solution of coordination polymer 24. Vittal and co-workers further reported a coordination polymer gel produced from linear bridging ligands and Ni(II) ion in an acidic medium [62]. An initial morphological study of the gel with SEM revealed no fibrous structure.…”

Modificação química do poli(3-hidroxibutirato) e preparação de membranas por eletrofiação para aplicação em biomateriais.

“…Em geral, na eletrofiação são usados solventes voláteis para facilitar sua remoção durante o processo. Porém, podem causar instabilidade do jato ou entupimento da ponta da agulha (Batabyal et al, 2009). Para a produção de nanofibras com aplicações biomédicas, recomenda-se o uso de clorofórmio como solvente, devido ao baixo ponto de ebulição, o que diminui a probabilidade de restar solvente no scaffold (Baker et al, 2006).…”