scholarly journals Direct Synthesis of Multiplexed Metal‐Nanowire‐Based Devices by Using Carbon Nanotubes as Vector Templates

2019 ◽  
Vol 131 (29) ◽  
pp. 10033-10037 ◽  
Author(s):  
Pierrick Clément ◽  
Xinzhao Xu ◽  
Craig T. Stoppiello ◽  
Graham A. Rance ◽  
Antonio Attanzio ◽  
...  
2019 ◽  
Vol 58 (29) ◽  
pp. 9928-9932
Author(s):  
Pierrick Clément ◽  
Xinzhao Xu ◽  
Craig T. Stoppiello ◽  
Graham A. Rance ◽  
Antonio Attanzio ◽  
...  

2017 ◽  
Vol 423 ◽  
pp. 283-292 ◽  
Author(s):  
Namjo Jeong ◽  
Eunjin Jwa ◽  
Chansoo Kim ◽  
Ji Yeon Choi ◽  
Joo-youn Nam ◽  
...  

2008 ◽  
Vol 8 (7) ◽  
pp. 3333-3342
Author(s):  
D. Barreca ◽  
W. J. Blau ◽  
F. C. Dillon ◽  
J. D. Holmes ◽  
C. Kufazvinei ◽  
...  

Metal oxide-based nanoparticles of cobalt or nickel were deposited inside the pores and on the surface of hexagonal mesoporous silicas by a direct synthesis technique using Pluronic P85 and P123 surfactants as structure directing agents with the appropriate metal phthalocyanine as a metal precursor. Metal loadings were between 0.4–3.2 wt.%. XPS studies showed that the initial form of the metal oxide nanoparticles were [CoO] and [NiO] respectively. Samples of these materials formed from the P85 surfactant and 3.0 wt.% were used to grow carbon nanotubes (CNTs) from acetylene feedstock in a catalytic chemical vapour deposition (CCVD) reactor at 800 °C. CNT growth appeared to be random and the CNTs had diameters ranging from <10 to >90 nm. Treatment of the metal impregnated silicas with nitric acid produced materials which, under the same CNT growth conditions, afforded more uniform CNTs with diameters between 5–15 nm. No significant loss in mesophase ordering was seen in the TEM, PXRD or nitrogen physisorption analysis of the acid washed samples. CNTs grown with cobalt impregnated silicas formed with the P123 surfactant had diameters in the range 15–25 nm. Raman spectroscopy of the CNT products showed the nanotubes were highly graphitised and of good quality.


2021 ◽  
Vol 12 (2) ◽  
pp. 135-143
Author(s):  
Yu. I. Sementsov ◽  
◽  
O. A. Cherniuk ◽  
S. V. Zhuravskyi ◽  
Wang Bo ◽  
...  

Nitrogen-containing carbon nanotubes (CNTs) were synthesized by the CVD method on oxide catalysts of Al-Fe-Mo-O by adding acetonitrile or ethylenediamine to the carbon source (propylene), or completely replacing it, as well as impregnating the original CNTs with urea, followed by heat treatment. The structure of nitrogen-containing CNTs (N-CNT) was characterized by the method of Raman scattering, transmission electron microscopy (TEM), differential thermal and gravimetric analysis (DTA, DTG) and X-ray photoelectron spectroscopy (XPS). The influence of the synthesis method on the number and chemical state of nitrogen heteroatoms in the structure of the carbon matrix is found. According to the TEM, nitrogen-containing CNTs have a characteristic bamboo-like structure, which is less perfect compared to the structure of the original CNTs: the characteristic Raman bands (G and D) are shifted to higher frequencies, their half-width and band D intensity increase relative to G. This is also manifested in the lower thermal stability of nitrogen-containing CNTs. According to the XPS, the direct synthesis of nitrogen-containing CNTs increases the total content of nitrogen atoms and the proportion of pyrrolic and quaternary nitrogen against the background of a significant decrease in the amount of pyridinic form. This can be explained by the fact that nitrogen is evenly distributed throughout the carbon matrix of CNTs, and during nitriding of CNTs with urea, nitrogen is included mainly in the surface layers and defects, because the pyridine form is characteristic of the edge location of the nitrogen atom in the graphene plane.The catalytic effect of multilayer nitrogen-containing carbon nanotubes (N-CNT) on the kinetics of decomposition of hydrogen peroxide in aqueous solutions at different pH values is considered. It is concluded that the method of direct synthesis of nitrogen-containing CNTs allows to obtain more catalytically active carbon nanotubes containing more nitrogen, mainly pyrrolic and quaternary type. It has been found that regardless of the method of synthesis, the maximum catalytic activity in the decomposition of hydrogen peroxide is observed at pH 7.


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