Combined Functionalization of Carbon Nanotubes (CNT) Fibers with H2SO4/HNO3 and Ca(OH)2 for Addition in Cementitious Matrix

Acid treatment is commonly used to improve the dispersion of carbon nanotubes (CNT) in a cementitious matrix, but it causes undesired delay on cement hydration kinetics. This work reports a combined CNT functionalization method with H2SO4/HNO3 and Ca(OH)2 for addition in a cementitious matrix. Results showed that the Ca(OH)2 exposure neutralized the active sites generated by acid exposure, compensating the delay in hydration. As a result, CNT exposed to H2SO4/HNO3 for 9 h and further Ca(OH)2 treatment led to equivalent hydration kinetics than un-treated CNT did with improved stability.

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Fast and clean functionalization of carbon nanotubes by dielectric barrier discharge plasma in air compared to acid treatment

Carbon ◽

10.1016/j.carbon.2009.12.027 ◽

2010 ◽

Vol 48 (5) ◽

pp. 1369-1379 ◽

Cited By ~ 104

Author(s):

Masoud Vesali Naseh ◽

Abbas Ali Khodadadi ◽

Yadollah Mortazavi ◽

Fathollah Pourfayaz ◽

Ommolbanin Alizadeh ◽

...

Keyword(s):

Carbon Nanotubes ◽

Dielectric Barrier Discharge ◽

Acid Treatment ◽

Discharge Plasma ◽

Barrier Discharge ◽

Dielectric Barrier Discharge Plasma ◽

Dielectric Barrier ◽

Barrier Discharge Plasma ◽

Functionalization Of Carbon Nanotubes

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FUNCTIONALIZATION OF CARBON NANOTUBES FOR MESENCHYMAL STEM CELL-ASSISTED PHOTOTHERMAL THERAPY

10.37099/mtu.dc.etd-restricted/233 ◽

2014 ◽

Author(s):

Ethan J. Weydemeyer

Keyword(s):

Carbon Nanotubes ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Photothermal Therapy ◽

Functionalization Of Carbon Nanotubes

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Insight on the active sites of CoNi alloy embedded in N-doped carbon nanotubes for oxygen reduction reaction

Science China Materials ◽

10.1007/s40843-021-1668-0 ◽

2021 ◽

Author(s):

Ying Wang ◽

Miaomiao Tong ◽

Lei Wang ◽

Xu Liu ◽

Chungui Tian ◽

...

Keyword(s):

Carbon Nanotubes ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Active Sites ◽

Reduction Reaction

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Effect of C-S-H Nucleating Agent on Cement Hydration

Applied Sciences ◽

10.3390/app11146638 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6638

Author(s):

Wenhao Zhao ◽

Xuping Ji ◽

Yaqing Jiang ◽

Tinghong Pan

Keyword(s):

Fractal Dimension ◽

Cement Hydration ◽

Nucleating Agent ◽

Crystal Nucleation ◽

Enhancement Effect ◽

Hydration Products ◽

Hydration Degree ◽

Hydration Kinetics ◽

Cement Mortars ◽

Early Strength

This work aims to study the effect of a nucleating agent on cement hydration. Firstly, the C-S-H crystal nucleation early strength agent (CNA) is prepared. Then, the effects of CNA on cement hydration mechanism, early strength enhancement effect, C-S-H content, 28-days hydration degree and 28-days fractal dimension of hydration products are studied by hydration kinetics calculation, resistivity test, BET specific surface area test and quantitative analysis of backscattered electron (BSE) images, respectively. The results show that CNA significantly improves the hydration degree of cement mixture, which is better than triethanolamine (TEA). CNA shortens the beginning time of the induction period by 49.3 min and the end time of the cement hydration acceleration period by 105.1 min than the blank sample. CNA increases the fractal dimension of hydration products, while TEA decreases the fractal dimension. CNA significantly improves the early strength of cement mortars; the 1-day and 3-days strength of cement mortars with CNA are more than the 3-days and 7-days strength of the blank sample. These results will provide a reference for the practical application of the C-S-H nucleating agent.

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