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Fabrication of thickness controllable free-standing sandwich-structured hybrid carbon film for high-rate and high-power supercapacitor.

Wei H, Wei S, Tian W, Zhu D, Liu Y, Yuan L, Li X - Sci Rep (2014)

Bottom Line: Here we demonstrate a simple approach to fabricate free-standing sandwich-structured hybrid carbon film composed of porous amorphous carbon film and multilayer graphene film by chemical vapor deposition in a controllable and scalable way.Supercapacitors assembled by hybrid carbon films exhibit ultrahigh rate capability, wide frequency range, good capacitance performance, and high-power density.Moreover, this approach may provide a general path for fabrication of hybrid carbon materials with different structures by using different metals with high carbon solubility, and greatly expands the application scope of carbon materials.

View Article: PubMed Central - PubMed

Affiliation: School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei. 430074, PR China.

ABSTRACT
Hybrid carbon films composed of graphene film and porous carbon film may give full play to the advantages of both carbon materials, and have great potential for application in energy storage and conversion devices. Unfortunately, there are very few reports on fabrication of hybrid carbon films. Here we demonstrate a simple approach to fabricate free-standing sandwich-structured hybrid carbon film composed of porous amorphous carbon film and multilayer graphene film by chemical vapor deposition in a controllable and scalable way. Hybrid carbon films reveal good electrical conductivity, excellent flexibility, and good compatibility with substrate. Supercapacitors assembled by hybrid carbon films exhibit ultrahigh rate capability, wide frequency range, good capacitance performance, and high-power density. Moreover, this approach may provide a general path for fabrication of hybrid carbon materials with different structures by using different metals with high carbon solubility, and greatly expands the application scope of carbon materials.

No MeSH data available.


Related in: MedlinePlus

Thickness and electrical property of carbon films.(a) Thickness of the PACF and MGF dependence of growth temperature and methane/hydrogen flow ratio, (b) Sheet resistivity of the carbon films dependence of the thickness of the PACF, insets are the photographic images of the samples.
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f5: Thickness and electrical property of carbon films.(a) Thickness of the PACF and MGF dependence of growth temperature and methane/hydrogen flow ratio, (b) Sheet resistivity of the carbon films dependence of the thickness of the PACF, insets are the photographic images of the samples.

Mentions: The thicknesses of the MGF and PACF are measured by cross sectional SEM images, and the thicknesses of thin MGF (<10 nm) are estimated from the SEM and TEM images. The effect of the growth temperature and flow ratio (CH4:H2) on the carbon film thickness is shown in Figure 5a. It is clear that the carbon film thicknesses increase with increasing the growth temperature. At high carbon source concentration (CH4:H2 = 80:8 sccm), the PACF thickness increases significantly at high temperature zone compared with that at low temperature zone. This is because that the solubility of carbon atoms in Ni increases exponentially with increasing the growth temperature28293031. The thickness of the PACF increases from 90 to 1000 nm as the growth temperature increases from 500 to 900°C. It should be pointed out that continuous PACF can not be obtained as the growth temperature is lower than 500°C because of the extremely low solubility of carbon atom28293031. Similar result is also observed for MGF growth, continuous MGF can be obtained only when the growth temperature is greater than 620°C. The thickness of the MGF increases from about 10 to 60 nm as the growth temperature increases from 620 to 900°C. At low carbon source concentration (CH4:H2 = 8:80 sccm), no MGF and PACF form as the growth temperature is lower than 600°C. Continuous PACF can be obtained when the growth temperature is greater than 700°C. The thickness of the PACF increases from 125 to 220 nm as the growth temperature increases from 700 to 900°C. Continuous MGF can be obtained as the growth temperature is greater than 850°C, and the thickness of the MGF increases from about 5 to 10 nm with increasing the growth temperature from 850 to 900°C. The above results suggest that the growth temperature and flow ratio (CH4:H2) greatly influence the growth of carbon film during APCVD growth process.


Fabrication of thickness controllable free-standing sandwich-structured hybrid carbon film for high-rate and high-power supercapacitor.

Wei H, Wei S, Tian W, Zhu D, Liu Y, Yuan L, Li X - Sci Rep (2014)

Thickness and electrical property of carbon films.(a) Thickness of the PACF and MGF dependence of growth temperature and methane/hydrogen flow ratio, (b) Sheet resistivity of the carbon films dependence of the thickness of the PACF, insets are the photographic images of the samples.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4231341&req=5

f5: Thickness and electrical property of carbon films.(a) Thickness of the PACF and MGF dependence of growth temperature and methane/hydrogen flow ratio, (b) Sheet resistivity of the carbon films dependence of the thickness of the PACF, insets are the photographic images of the samples.
Mentions: The thicknesses of the MGF and PACF are measured by cross sectional SEM images, and the thicknesses of thin MGF (<10 nm) are estimated from the SEM and TEM images. The effect of the growth temperature and flow ratio (CH4:H2) on the carbon film thickness is shown in Figure 5a. It is clear that the carbon film thicknesses increase with increasing the growth temperature. At high carbon source concentration (CH4:H2 = 80:8 sccm), the PACF thickness increases significantly at high temperature zone compared with that at low temperature zone. This is because that the solubility of carbon atoms in Ni increases exponentially with increasing the growth temperature28293031. The thickness of the PACF increases from 90 to 1000 nm as the growth temperature increases from 500 to 900°C. It should be pointed out that continuous PACF can not be obtained as the growth temperature is lower than 500°C because of the extremely low solubility of carbon atom28293031. Similar result is also observed for MGF growth, continuous MGF can be obtained only when the growth temperature is greater than 620°C. The thickness of the MGF increases from about 10 to 60 nm as the growth temperature increases from 620 to 900°C. At low carbon source concentration (CH4:H2 = 8:80 sccm), no MGF and PACF form as the growth temperature is lower than 600°C. Continuous PACF can be obtained when the growth temperature is greater than 700°C. The thickness of the PACF increases from 125 to 220 nm as the growth temperature increases from 700 to 900°C. Continuous MGF can be obtained as the growth temperature is greater than 850°C, and the thickness of the MGF increases from about 5 to 10 nm with increasing the growth temperature from 850 to 900°C. The above results suggest that the growth temperature and flow ratio (CH4:H2) greatly influence the growth of carbon film during APCVD growth process.

Bottom Line: Here we demonstrate a simple approach to fabricate free-standing sandwich-structured hybrid carbon film composed of porous amorphous carbon film and multilayer graphene film by chemical vapor deposition in a controllable and scalable way.Supercapacitors assembled by hybrid carbon films exhibit ultrahigh rate capability, wide frequency range, good capacitance performance, and high-power density.Moreover, this approach may provide a general path for fabrication of hybrid carbon materials with different structures by using different metals with high carbon solubility, and greatly expands the application scope of carbon materials.

View Article: PubMed Central - PubMed

Affiliation: School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei. 430074, PR China.

ABSTRACT
Hybrid carbon films composed of graphene film and porous carbon film may give full play to the advantages of both carbon materials, and have great potential for application in energy storage and conversion devices. Unfortunately, there are very few reports on fabrication of hybrid carbon films. Here we demonstrate a simple approach to fabricate free-standing sandwich-structured hybrid carbon film composed of porous amorphous carbon film and multilayer graphene film by chemical vapor deposition in a controllable and scalable way. Hybrid carbon films reveal good electrical conductivity, excellent flexibility, and good compatibility with substrate. Supercapacitors assembled by hybrid carbon films exhibit ultrahigh rate capability, wide frequency range, good capacitance performance, and high-power density. Moreover, this approach may provide a general path for fabrication of hybrid carbon materials with different structures by using different metals with high carbon solubility, and greatly expands the application scope of carbon materials.

No MeSH data available.


Related in: MedlinePlus