RESUMEN
The scope of CCC-NHC pincer complex synthetic methodology by metalation/transmetalation has been extended to Ir. Structural characterization revealed that it is isomorphous with the Rh complex. Both Rh and Ir complexes are efficient catalysts for the hydroamination/cyclization of secondary amines in the presence of air and/or water.
RESUMEN
Biological molecules such as deoxyribonucleic acid (DNA) possess inherent recognition and self-assembly capabilities, and are attractive templates for constructing functional hierarchical material structures as building blocks for nanoelectronics. Here we report the assembly and electronic functionality of nanoarchitectures based on conjugates of single-walled carbon nanotubes (SWNTs) functionalized with carboxylic groups and single-stranded DNA (ssDNA) sequences possessing terminal amino groups on both ends, hybridized together through amide linkages by adopting a straightforward synthetic route. Morphological and chemical-functional characterization of the nanoarchitectures are investigated using scanning electron microscopy, transmission electron microscopy, atomic force microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy, and Fourier-transform infrared spectroscopy. Electrical measurements (I-V characterization) of the nanoarchitectures demonstrate negative differential resistance in the presence of SWNT/ssDNA interfaces, which indicates a biomimetic route to fabricating resonant tunneling diodes. I-V characterization on platinum-metallized SWNT-ssDNA nanoarchitectures via salt reduction indicates modulation of their electrical properties, with effects ranging from those of a resonant tunneling diode to a resistor, depending on the amount of metallization. Electron transport through the nanoarchitectures has been analyzed by density functional theory calculations. Our studies illustrate the great promise of biomimetic assembly of functional nanosystems based on biotemplated materials and present new avenues toward exciting future opportunities in nanoelectronics and nanobiotechnology.
Asunto(s)
ADN/química , Nanotubos de Carbono/química , Platino (Metal)/química , ADN de Cadena Simple/química , Electroquímica/métodos , Electrónica , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión , Modelos Teóricos , Nanopartículas , Nanotecnología/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Espectrometría Raman , TemperaturaRESUMEN
Fabrication of perforated organometallic nanotubes using a di-rhodium bis(N-heterocyclic carbene) complex by a simple nanoporous template wetting technique is described along with characterization data from scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), proton NMR and Mass spectroscopy.