How PL Molecular Photoluminescence Spectroscopy in Nanotubes (CNTs and CNTs) PhD Nano _ Microelectronics

Researcher  and author: Dr.   (   Afshin Rashid)






Note: In photoluminescence spectroscopy in nanotubes (CNTs and CNTs), external factors affecting the fluorescence intensity of growth defect, nanotube length, molecules in the environment, physical or chemical degradation and chemical performance. Interaction between guest molecules by covalent and non-covalent methods with host nanotubes can lead to intensification or inactivation of PL intensity. 

PL spectroscopy provides good information    about CNT semiconductor nanotubes and CNTs in the sample    . This can be used to    arrange the sample based on the structure or measure the    selective production of a species of the resulting sample in    a rapid manner. Of course   , there are many   external factors    that   reduce the   accuracy of the data obtained,    and more calculations and   accurate   calibration    increase the accuracy of the work.

CNT and CNTS electrical conductivity measurements

Metal and semiconductor SWCNTs   with  electrical properties   There are  several differences   in  their conductivity measurements   Reflect  the   will   . In theory, metal nanotubes    can   pass   an electric current density of    4 109 109 which is 1000 times more    ACM-2    than metals such as copper, whereas    metal unlike   SWCNTs semiconductors   has   electrons having DOS at the    surface and surface. Fermi is   the chemical   potential of    electrons. At zero, this    surface contains electrons, but in semiconductors    electrons are placed in the energy gap, where  There is no energy level allowed. Thus, electrons   exist   to stabilize the complex transport   formed by increasing the   reaction to   Nanotube surface.


 Metal    swcnts are   better able to stabilize the converter and    therefore increase the reaction speed. Selective removal of semiconductor SWCNTs is related    to cavity doping with hydrogen peroxide. If surfactant is used, the    diameter of  the hydrogen peroxide decomposition reaction    increases with diameter because the SWCNTs   in which the surfactant is placed    react more strongly than the others. Oxidation of nanotubes with air   can be   compared   with    oxidation of nanotubes with hydrogen peroxide    . Under   air   oxidation conditions    , SWCNTs do not   react With higher chiral angle and    lower diameter faster. So    you can angle and diameter of the SWCNT with low catch   up    .

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 Similarly, the solubility of a solution    indicates that the reaction rate   depends    on the diameter   because the pyramidal or nonlinear reaction    on the π orbit is    a diameter-dependent process. While    exposed to air, metal SWCNTs in    the thin layer of carbon nanotubes can   be  selectively degraded   in the presence    of the semiconductor type  . Nitronium ions have been reported to    be selectively incorporated   into  low diameter metal SWCNTs   Attack   and  they  are amorphous carbon   Turns   out   . Sulfonic acid   binary   mixtures  are   also used to dissolve SWCNTs by direct protonation    . From    there, proton chain geometry    is sensitive, this selection method  based on the diameter to  allow it    . 




Conclusion : 

Reaction with hydrogen gas and fluorine, with the introduction of    SP3,   transforms   the electrical structure    of hybridization    metal nanotubes   into a semiconductor. These reactions sometimes  the walls of the nanotubes  damage    resulting    layer structure  of carbon or  graphite,   amorphous create   them    . Hydrogenation of single-walled nanotubes   increases the  nature   SWCNT semiconductors   are made at natural temperatures    . Engraving  plasma reaction    or   high temperature   in the wall   of metal   nanotubes    .

Researcher  and author: Dr.   (   Afshin Rashid)

PhD in Nano-Microelectronics