- Email: [email protected]
carbon composites as rocket throats
CARBON 51 (2013) 435– 438
437
showed that nitrogen content and d002 decreased, and carbon con-
Ordered mesoporous carbons were prepared by pyrolysis of
tent and La increased with HTT temperature. La increased sharply
polymer blends, which were formed by the organic–organic self-
with temperature above 1900 °C. The Raman spectra taken at four
assembly of resorcinol–formaldehyde pre-polymers and tri-block
points in radial directions indicated that the intensity of the G
copolymers under acidic conditions. The tri-block copolymer
band at the skin was stronger than at the core with no change in
mixtures of F127 and P123 were used as structure-directing
peak position at 1700 °C. However, the G peak position decreased
agents. The samples were characterized by X-ray diffraction,
from 1588.2 to 1582.2 cm 1, the width of the G band at half maxi-
transmission electron microscopy and nitrogen adsorption.
mum intensity decreased from 46.3 to 28.9 and that of D band
Results show that the degree of order of mesoporous carbons
1
from core to skin after HTT at 2500 °C.
exhibits a maximum with increasing holding time from 24 to
The differences of microstructure in the core and skin at different
72 h. When the molar ratio of the F127 to P123 is 1, the mesopor-
temperatures are related closely to the differences in nitrogen
ous carbon obtained has the most ordered hexagonal mesostruc-
removal efficiency and temperature. At temperatures below
ture (Pm6m), with a typical BET surface area of 640.3 m2/g, pore
1900 °C, nitrogen near the skin is more easily removed due to a
size of 3.7 nm and pore volume of 0.59 cm3/g.
from 46.9 to 36.7 cm
shorter diffusion path and a higher temperature on the skin, leading to a slower increase of La with temperature on the skin than in
[New Carbon Materials 2012, 27(4): 301–306]
the core. At temperatures above 1900 °C, nitrogen is removed com-
doi:10.1016/j.carbon.2012.08.040
pletely and graphitization on the skin is more rapid than in the core, leading to a large skin-core difference with the skin portion having a high modulus and the core portion a high strength. [New Carbon Materials 2012, 27(4): 288–293] doi:10.1016/j.carbon.2012.08.038
Intermittent growth of a diamond film by direct current hot cathode plasma chemical vapor deposition Hong-wei Jiang, Hai-liang Huang, Xiang-hua Jia, Long-cheng Yin, Yu-qiang Chen, Hong-yan Peng Department of Physics, Mudanjiang Normal College, Mudanjiang
Preparation of activated carbons by ZnCl2 activation from herb
157012, China
residues under vacuum Juan Yang, Ke-qiang Qiu
A diamond film was intermittently prepared by direct-current
School of Chemistry and Chemical Engineering, Central South Univer-
(DC) hot-cathode plasma chemical vapor deposition (PCVD). The
sity, Changsha, Hunan 410083, China
intermittent growth was carried out by alternating deposition under methane flow for 20 min and etching for 10 min without methane flow. For comparison, a diamond film was continuously
Activated carbons were prepared by ZnCl2 activation from
prepared under the same growth conditions without etching.
herb residues under an absolute pressure of 30 kPa and the Doehl-
Scanning electron microscopy, Raman spectroscopy and XRD
ert matrix was used to optimize activation temperature and
were used to characterize surface morphology, texture and purity
impregnation ratio based on adsorption capacities of methylene
of the two diamond films. Results indicated that the diamond film
blue and iodine by the activated carbons. Results showed that
produced by the intermittent growth had smaller amounts of
activation temperature and impregnation ratio had little effect
non-diamond phase and its grains were more uniform than that
on the total yield of the activated carbons. The activation temper-
produced by the continuous growth without etching. Amorphous
ature had a greater influence than the impregnation ratio in
carbon and graphite formed during deposition on the surface of
methylene blue and iodine adsorption. The optimized activated
the diamond film can be reduced by etching.
carbon was obtained under an activation temperature of 474 °C and an impregnation ratio of 1.225, and had a methylene blue
[New Carbon Materials 2012, 27(4): 307–310]
value and an iodine value of 316 and 994 mg g 1, respectively.
doi:10.1016/j.carbon.2012.08.041
The experimental values agree well with those calculated from the Doehlert model. The activated carbon optimized in this study had a higher adsorption capacity compared with commercial ones. [New Carbon Materials 2012, 27(4): 294–300] doi:10.1016/j.carbon.2012.08.039
Effect of hafnium carbide content on the ablative performance of carbon/carbon composites as rocket throats Shu-ping Lia, Ke-zhi Lia, Hong-ying Dub, Shou-yan Zhanga, Xuetao Shena a
School of Materials Science and Engineering, Northwestern Polytech-
nical University, Xi’an 710072, China b
Synthesis of ordered mesoporous carbon with dual templates as structure directing agents
Institute of Product Design, Jinxi Machinery Industries Group Corpo-
ration, Taiyuan 030027, China
Yu Zhang, Tong-hua Wang, Pan-pan Mi State Key Laboratory of Fine Chemicals, Carbon Research Laboratory,
Hafnium carbide (HfC) modified carbon/carbon (HfC-C/C)
School of Chemical Engineering, Dalian University of Technology, Dalian
composites were prepared by impregnating carbon felts with a
116012, China
saturated HfOCl2 8H2O ethanol solution and heat treating at
438
CARBON 51 (2013) 435– 438
600 °C to form HfO2/C composites that were then densified with
ity. Research on the structure and properties of graphene is mov-
pyrocarbon by chemical vapor infiltration and graphitized at
ing from curiosity-oriented to application-oriented. Mathematical
2100 °C to convert HfO2 into HfC. The HfC-C/C composites as
formulation or modeling of pore structures has been promoted by
rocket throats were ablated at 7 MPa and around 3200 °C for 3 s
the progress in characterization methods. The modification of the
by an experimental solid rocket motor. Results showed that the
surface/interface in carbon materials, which plays important
HfC-C/C composites with HfC contents more than 5.7 wt.% had
roles in determining their physical, chemical or mechanical prop-
a stable period with a constant ablation rate and the duration of
erties is still a focus of research activity in carbon materials.
this period increased with HfC content. The overall ablation rate was decreased by 25.2% and 49.6% for the composites having
[New Carbon Materials 2012, 27(4): 315–318]
5.7 and 8.7 wt.% HfC respectively as compared with the composite
doi:10.1016/j.carbon.2012.08.043
with 2.5 wt.% HfC. [New Carbon Materials 2012, 27(4): 311–314] doi:10.1016/j.carbon.2012.08.042
A brief overview of the Tenth Cross-Strait Symposium on Carbon Materials Jia Li, Fei-yu Kang
How will carbon material lead to a Low Carbon Society – A review of Carbon 2012 Xu-guang Liu
Shenzhen Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong 518055, PR China
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China
The Tenth Cross-Strait Symposium on Carbon Materials was
Key Laboratory of Interface Science and Engineering in Advanced
held in Baotou City, Inner Mongolia, PR China from August 1 to
Materials, Taiyuan University of Technology, Ministry of Education,
4, 2012. It was hosted by Tsinghua University and Inner Mongolia
Taiyuan, Shanxi 030024, China
University of Science & Technology. More than 60 cross-strait carbon scientists participated in the conference, and 31 presentations were given, including 15 keynote talks and 16 oral
A review is given of the Annual World Conference on Carbon,
presentations. The presentations were classified into the follow-
which was held on June 17–22, 2012 in Krakow, Poland and orga-
ing eight topics: highly efficient conversion and applications of
nized by the Polish Carbon Society. In this conference, 5 plenary
coal, carbon fibers and carbon-based composites, special car-
lectures, 30 keynote lectures, 220 oral presentations and 465 post-
bon-graphite materials, nano-structured carbons and their appli-
ers were divided into 10 topics, i.e., carbons for energy storage;
cations, carbon materials for energy storage, preparation and
carbons for health and environmental protection; precursors,
applications of graphene, evaluation and performance of new car-
processing and technology; carbon nanomaterials; porous car-
bon materials, and other new carbon materials. The 4-day sym-
bons; carbon-based composites; graphene; new methods for car-
posium has increased cross-strait academic exchange and has
bon characterization; computation and modeling; and industrial
advocated close academic cooperation in the field of carbon
news. Besides traditional modification on surface area and poros-
materials.
ity, doping with hetero atoms such as N, B and P or compositing with metals or metal oxides have been developed into effective
[New Carbon Materials 2012, 27(4): 319–320]
means for modifying carbon materials for improved adsorption,
doi:10.1016/j.carbon.2012.08.044
catalysis and energy-storage performance. The applications of novel carbon structures like nanotubes are still limited by the controllable and scalable preparation, processability and reactiv-
437
showed that nitrogen content and d002 decreased, and carbon con-
Ordered mesoporous carbons were prepared by pyrolysis of
tent and La increased with HTT temperature. La increased sharply
polymer blends, which were formed by the organic–organic self-
with temperature above 1900 °C. The Raman spectra taken at four
assembly of resorcinol–formaldehyde pre-polymers and tri-block
points in radial directions indicated that the intensity of the G
copolymers under acidic conditions. The tri-block copolymer
band at the skin was stronger than at the core with no change in
mixtures of F127 and P123 were used as structure-directing
peak position at 1700 °C. However, the G peak position decreased
agents. The samples were characterized by X-ray diffraction,
from 1588.2 to 1582.2 cm 1, the width of the G band at half maxi-
transmission electron microscopy and nitrogen adsorption.
mum intensity decreased from 46.3 to 28.9 and that of D band
Results show that the degree of order of mesoporous carbons
1
from core to skin after HTT at 2500 °C.
exhibits a maximum with increasing holding time from 24 to
The differences of microstructure in the core and skin at different
72 h. When the molar ratio of the F127 to P123 is 1, the mesopor-
temperatures are related closely to the differences in nitrogen
ous carbon obtained has the most ordered hexagonal mesostruc-
removal efficiency and temperature. At temperatures below
ture (Pm6m), with a typical BET surface area of 640.3 m2/g, pore
1900 °C, nitrogen near the skin is more easily removed due to a
size of 3.7 nm and pore volume of 0.59 cm3/g.
from 46.9 to 36.7 cm
shorter diffusion path and a higher temperature on the skin, leading to a slower increase of La with temperature on the skin than in
[New Carbon Materials 2012, 27(4): 301–306]
the core. At temperatures above 1900 °C, nitrogen is removed com-
doi:10.1016/j.carbon.2012.08.040
pletely and graphitization on the skin is more rapid than in the core, leading to a large skin-core difference with the skin portion having a high modulus and the core portion a high strength. [New Carbon Materials 2012, 27(4): 288–293] doi:10.1016/j.carbon.2012.08.038
Intermittent growth of a diamond film by direct current hot cathode plasma chemical vapor deposition Hong-wei Jiang, Hai-liang Huang, Xiang-hua Jia, Long-cheng Yin, Yu-qiang Chen, Hong-yan Peng Department of Physics, Mudanjiang Normal College, Mudanjiang
Preparation of activated carbons by ZnCl2 activation from herb
157012, China
residues under vacuum Juan Yang, Ke-qiang Qiu
A diamond film was intermittently prepared by direct-current
School of Chemistry and Chemical Engineering, Central South Univer-
(DC) hot-cathode plasma chemical vapor deposition (PCVD). The
sity, Changsha, Hunan 410083, China
intermittent growth was carried out by alternating deposition under methane flow for 20 min and etching for 10 min without methane flow. For comparison, a diamond film was continuously
Activated carbons were prepared by ZnCl2 activation from
prepared under the same growth conditions without etching.
herb residues under an absolute pressure of 30 kPa and the Doehl-
Scanning electron microscopy, Raman spectroscopy and XRD
ert matrix was used to optimize activation temperature and
were used to characterize surface morphology, texture and purity
impregnation ratio based on adsorption capacities of methylene
of the two diamond films. Results indicated that the diamond film
blue and iodine by the activated carbons. Results showed that
produced by the intermittent growth had smaller amounts of
activation temperature and impregnation ratio had little effect
non-diamond phase and its grains were more uniform than that
on the total yield of the activated carbons. The activation temper-
produced by the continuous growth without etching. Amorphous
ature had a greater influence than the impregnation ratio in
carbon and graphite formed during deposition on the surface of
methylene blue and iodine adsorption. The optimized activated
the diamond film can be reduced by etching.
carbon was obtained under an activation temperature of 474 °C and an impregnation ratio of 1.225, and had a methylene blue
[New Carbon Materials 2012, 27(4): 307–310]
value and an iodine value of 316 and 994 mg g 1, respectively.
doi:10.1016/j.carbon.2012.08.041
The experimental values agree well with those calculated from the Doehlert model. The activated carbon optimized in this study had a higher adsorption capacity compared with commercial ones. [New Carbon Materials 2012, 27(4): 294–300] doi:10.1016/j.carbon.2012.08.039
Effect of hafnium carbide content on the ablative performance of carbon/carbon composites as rocket throats Shu-ping Lia, Ke-zhi Lia, Hong-ying Dub, Shou-yan Zhanga, Xuetao Shena a
School of Materials Science and Engineering, Northwestern Polytech-
nical University, Xi’an 710072, China b
Synthesis of ordered mesoporous carbon with dual templates as structure directing agents
Institute of Product Design, Jinxi Machinery Industries Group Corpo-
ration, Taiyuan 030027, China
Yu Zhang, Tong-hua Wang, Pan-pan Mi State Key Laboratory of Fine Chemicals, Carbon Research Laboratory,
Hafnium carbide (HfC) modified carbon/carbon (HfC-C/C)
School of Chemical Engineering, Dalian University of Technology, Dalian
composites were prepared by impregnating carbon felts with a
116012, China
saturated HfOCl2 8H2O ethanol solution and heat treating at
438
CARBON 51 (2013) 435– 438
600 °C to form HfO2/C composites that were then densified with
ity. Research on the structure and properties of graphene is mov-
pyrocarbon by chemical vapor infiltration and graphitized at
ing from curiosity-oriented to application-oriented. Mathematical
2100 °C to convert HfO2 into HfC. The HfC-C/C composites as
formulation or modeling of pore structures has been promoted by
rocket throats were ablated at 7 MPa and around 3200 °C for 3 s
the progress in characterization methods. The modification of the
by an experimental solid rocket motor. Results showed that the
surface/interface in carbon materials, which plays important
HfC-C/C composites with HfC contents more than 5.7 wt.% had
roles in determining their physical, chemical or mechanical prop-
a stable period with a constant ablation rate and the duration of
erties is still a focus of research activity in carbon materials.
this period increased with HfC content. The overall ablation rate was decreased by 25.2% and 49.6% for the composites having
[New Carbon Materials 2012, 27(4): 315–318]
5.7 and 8.7 wt.% HfC respectively as compared with the composite
doi:10.1016/j.carbon.2012.08.043
with 2.5 wt.% HfC. [New Carbon Materials 2012, 27(4): 311–314] doi:10.1016/j.carbon.2012.08.042
A brief overview of the Tenth Cross-Strait Symposium on Carbon Materials Jia Li, Fei-yu Kang
How will carbon material lead to a Low Carbon Society – A review of Carbon 2012 Xu-guang Liu
Shenzhen Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong 518055, PR China
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China
The Tenth Cross-Strait Symposium on Carbon Materials was
Key Laboratory of Interface Science and Engineering in Advanced
held in Baotou City, Inner Mongolia, PR China from August 1 to
Materials, Taiyuan University of Technology, Ministry of Education,
4, 2012. It was hosted by Tsinghua University and Inner Mongolia
Taiyuan, Shanxi 030024, China
University of Science & Technology. More than 60 cross-strait carbon scientists participated in the conference, and 31 presentations were given, including 15 keynote talks and 16 oral
A review is given of the Annual World Conference on Carbon,
presentations. The presentations were classified into the follow-
which was held on June 17–22, 2012 in Krakow, Poland and orga-
ing eight topics: highly efficient conversion and applications of
nized by the Polish Carbon Society. In this conference, 5 plenary
coal, carbon fibers and carbon-based composites, special car-
lectures, 30 keynote lectures, 220 oral presentations and 465 post-
bon-graphite materials, nano-structured carbons and their appli-
ers were divided into 10 topics, i.e., carbons for energy storage;
cations, carbon materials for energy storage, preparation and
carbons for health and environmental protection; precursors,
applications of graphene, evaluation and performance of new car-
processing and technology; carbon nanomaterials; porous car-
bon materials, and other new carbon materials. The 4-day sym-
bons; carbon-based composites; graphene; new methods for car-
posium has increased cross-strait academic exchange and has
bon characterization; computation and modeling; and industrial
advocated close academic cooperation in the field of carbon
news. Besides traditional modification on surface area and poros-
materials.
ity, doping with hetero atoms such as N, B and P or compositing with metals or metal oxides have been developed into effective
[New Carbon Materials 2012, 27(4): 319–320]
means for modifying carbon materials for improved adsorption,
doi:10.1016/j.carbon.2012.08.044
catalysis and energy-storage performance. The applications of novel carbon structures like nanotubes are still limited by the controllable and scalable preparation, processability and reactiv-