Revealing the impact of catalyst phase transition on carbon nanotube growth by in situ Raman spectroscopy.
نویسندگان
چکیده
The physical state of the catalyst and its impact on the growth of single-walled carbon nanotubes (SWNTs) is the subject of a long-standing debate. We addressed it here using in situ Raman spectroscopy to measure Fe and Ni catalyst lifetimes during the growth of individual SWNTs across a wide range of temperatures (500-1400 °C). The temperature dependence of the Fe catalyst lifetimes underwent a sharp increase around 1100 °C due to a solid-to-liquid phase transition. By comparing experimental results with the metal-carbon phase diagrams, we prove that SWNTs can grow from solid and liquid phase-catalysts, depending on the temperature.
منابع مشابه
Catalyst of Ni and Co dependencies for carbon nanotube synthesis by CVD method
In this research, the effect of catalyst type on the CNTs synthesis was investigated. The carbonnanotubes (CNTs) were produced on stainless steel substrates and two of catalyst with differentcharacteristics by using Thermal chemical vapor deposition (TCVD) method. The catalysts have theimportant role for the growth carbon nanotubes (CNTs). Acetylene gas (C2H2) diluted by NH3 wasused as the reac...
متن کاملThe Impact of Cadmium Loading In Fe/Alumina Catalysts and Synthesis Temperature on Carbon Nanotubes Growth by Chemical Vapor Deposition Method
We evaluated the effect of Fe/Alumina Catalyst contained different Cadmium contents and two synthesis temperatures on producing carbon nanotubes by chemical vapor deposition of methane as a feedstock. X-ray powder diffraction (XRD), N2 adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and Thermogravimetry analysis (TGA) were u...
متن کاملEffect of Catalyst on the Growth of Diamond-like Carbon by HFCVD
Diamond like carbon (DLC) film was grown by hot filament chemical vapor deposition (HFCVD)technique. In the present work, we investigated the quality of the DLC films groew on the substratesthat were coated with various metal nanocatalysts (Au and Ni). A combination of CH4/Ar/H2 rendersthe growth of carbon nanostructures technique (diamond like carbon). The utilized samples werecharacterized by...
متن کاملIn situ observations of catalyst dynamics during surface-bound carbon nanotube nucleation.
We present atomic-scale, video-rate environmental transmission electron microscopy and in situ time-resolved X-ray photoelectron spectroscopy of surface-bound catalytic chemical vapor deposition of single-walled carbon nanotubes and nanofibers. We observe that transition metal catalyst nanoparticles on SiOx support show crystalline lattice fringe contrast and high deformability before and durin...
متن کاملSynthesis and Characterization of Carbon Nanotubes Catalyzed by TiO2 Supported Ni, Co and Ni-Co Nanoparticles via CCVD
Monometallic and bimetallic Ni and Co catalytic nanoparticles supported on Titanium dioxide (rutile phase) substrate were prepared by wet impregnation method. These nanoparicles were used as catalysts for synthesis of multiwalled carbon nanotubes (MWCNTs) from acetylene decomposition at 700°C by the catalytic chemical vapor deposition (CCVD) technique. The nanomaterials (catalyst and CNTs) were...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- ACS nano
دوره 7 2 شماره
صفحات -
تاریخ انتشار 2013