Platinum(II)‐Coordinated Pyridine‐Functionalized Single‐Wall Carbon Nanotubes and Electron Transport in Their Films

Abstract

Carbon nanotubes (CNTs) are ideal support materials for platinum in fuel cells. However,l ittle is known about the conduction mechanism of Pt-coordinated CNTs. Herein, ac oordination complexo fp yridine-functionalized singlewalled nanotubes (Py-SWNTs) with Pt (Pt/Py-SWNTs) was prepared via the ligand exchange reaction between cis-[Pt(dmso) 2 Cl 2 ]a nd Py-SWNTsg enerated by pyridine diazonium salt addition to SWNTs. The presence of Pt in modified SWNTsw as confirmed by X-ray photoelectron spectroscopy (XPS). The N1 sX PS spectra provided evidence of Pt coordination to the pyridine nitrogen atom. Modified SWNTsw ere furtherc haracterized by thermogravimetric analysisc oupled with mass spectrometry,u ltraviolet-visible-near infrared spectroscopy,R amans pectroscopy,a nd elemental analysis. The electron conduction mechanism of Pt/Py-SWNT films was bestd escribed by am odified quantum tunneling model,i dentified from ac ombined analysis of the voltage and temperature dependence of the current.

Functionalized Carbon Nanotubes with Ni(II) Bipyridine Complexes as Efficient Catalysts for the Alkaline Oxygen Evolution Reaction

“…To investigate this further, the N 1s peak of Bipy-MWNT has been deconvoluted, assuming the presence of four peaks at 398.9 (N 1 ), 400.0 (N 2 ), 401.2 (N 3 ), and 405.4 eV (N 4 ). The N 1 peak is attributed to the typical characteristic peak for pyridinic nitrogen. ,, The N 2 peak is assigned to azo/azoxy groups, resulting from the side reactions of the diazonium salt , and/or possible amino groups either left over from incompletely reacted amino-bipyridine or from reduction of nitro groups under the X-ray beam. , The N 3 peak can be attributed to protonated pyridinic nitrogen (pyridinium salt) , formed in the acetic acid. The N 4 peak is assigned to nitro/nitrite species, probably originating from the sodium nitrite precursor.…”

“…The N 1 peak is attributed to the typical characteristic peak for pyridinic nitrogen. 22,24,63 The N 2 peak is assigned to azo/azoxy groups, resulting from the side reactions of the diazonium salt 64,65 and/or possible amino groups either left over from incompletely reacted amino-bipyridine or from reduction of nitro groups under the X-ray beam. 61, 65 The N 3 peak can be attributed to protonated pyridinic nitrogen (pyridinium salt) 22,63 formed in the acetic acid.…”

“…Incorporating the Ni complexes onto the sidewalls of the CNTs via covalent immobilization can produce a stable hybrid material with efficient charge transfer between the CNTs and the complexes. Among different strategies for covalent functionalization of CNTs, diazonium salt addition to the surface of single-walled carbon nanotubes (SWNTs) has been widely used because of its high efficiency and versatility. − Diazonium salt functionalization has been also performed to coordinate metal-based catalysts to the SWNTs as the support to develop stable hybrid materials. However, the sp 2 hybridization of the hexagonal structure of the sidewalls of the SWNTs is disturbed by the covalent functionalization and therefore the conductivity of the SWNTs is dramatically degraded.…”

Hybrid Materials Based on Carbon Nanotubes and Polyaromatic Molecules: Methods of Functionalization and Sensor Properties

“…An interesting unusual method for the preparation of 3D CNT structures was proposed by Jombert el al. [79] Nanotubes were cross-linked by the ligand exchange reaction between cis-[Pt(dmso) 2 Cl 2 ] and pyridine-functionalized single walled carbon nanotubes (Py-SWCNT) (Figure 10). Platinum was confirmed by XPS to coordinate the pyridine nitrogen atoms.…”

Mono‐Acetylenes as New Crosslinkers for All‐Carbon Living Charge Carbon Nanotubide Organogels

“…[8] Most physical gelation strategies rely on the non-covalent interaction of bi-and multi-functional bridging molecules/polymers with CNMs (e. g. ferrocene-grafted poly(p-phenyleneethynylene)s [9] and oligo(p-phenylene vinylene)s [10] etc.). In contrast, covalent strategies exploit chemical reactions between surface-modified CNMs and biand multi-functional organic/inorganic cross-linkers (e. g. diazidocarbonates, [11] 1,2-dibromoethane, [12] 1,4-diethynyl compounds, [13] 1,2-diphenyl-diacetylene, [14] ethylenediamine, [15] poly(allylamine) [16] and cis-[Pt(dmso) 2 Cl 2 ] [17] etc.). Direct and spacer-free crosslinking of surface-modified single-walled carbon nanotubes (SWCNTs) containing multiple reactive free radicals generated by reductive defluorination of highly fluorinated SWCNTs was reported under ambient temperature through inter-tube radical recombination.…”