Enhanced Mechanical and Durability Properties of Cement Mortar by Using Alumina Nanocoating on Carbon Nanofibers
This study evaluated the effect of carbon nanofibers (CNFs) coated by aluminum oxide Al<sub>2</sub>O<sub>3</sub> as a reinforcement on compressive strength, frost resistance, and drying shrinkage of cement mortars. Three weight ratios of 0.125%, 0.25%, and 0.5% of Al<sub&g...
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MDPI AG
2022-04-01
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| Online Access: | https://www.mdpi.com/1996-1944/15/8/2768 |
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| author | Huda Al Qader Ahmed M. Jasim Hani Salim Yangchuan Xing David Stalla |
| author_facet | Huda Al Qader Ahmed M. Jasim Hani Salim Yangchuan Xing David Stalla |
| author_sort | Huda Al Qader |
| collection | DOAJ |
| description | This study evaluated the effect of carbon nanofibers (CNFs) coated by aluminum oxide Al<sub>2</sub>O<sub>3</sub> as a reinforcement on compressive strength, frost resistance, and drying shrinkage of cement mortars. Three weight ratios of 0.125%, 0.25%, and 0.5% of Al<sub>2</sub>O<sub>3</sub>/CNFs and bare CNF cement mortars were compared with reference cement mortar samples. The reactive porous and high surface area layer of alumina induced the hydration reaction and promoted the production of well-distributed hydration gel. Derivative thermal analysis–differential thermogravimetric (TGA-DTG) and X-ray powder diffraction (XRD) characterization showed that Al<sub>2</sub>O<sub>3</sub>/CNFs reinforcement led to greater hydration gel production than bare CNFs. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were performed to study the coating and microstructure of the cement mortars evaluated in this paper. The results show that the optimum enhancement of the cement mortar properties was obtained at ratios of 0.125% for Al<sub>2</sub>O<sub>3</sub>/CNFs and 0.25% for CNFs. This enhancement was greater with Al<sub>2</sub>O<sub>3</sub>/CNFs-reinforced specimens in terms of high compressive strength, less compressive strength degradation after 150 cycles, and less drying shrinkage. The low use of the CNFs in Al<sub>2</sub>O<sub>3</sub>/CNFs samples indicates the coating is an economical and promising approach for improving the performance of cement mortars. |
| first_indexed | 2024-03-09T04:28:41Z |
| format | Article |
| id | doaj.art-59a8837cf1494609b049d18456c7c724 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-09T04:28:41Z |
| publishDate | 2022-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-59a8837cf1494609b049d18456c7c7242023-12-03T13:38:06ZengMDPI AGMaterials1996-19442022-04-01158276810.3390/ma15082768Enhanced Mechanical and Durability Properties of Cement Mortar by Using Alumina Nanocoating on Carbon NanofibersHuda Al Qader0Ahmed M. Jasim1Hani Salim2Yangchuan Xing3David Stalla4Department of Environmental and Civil Engineering, University of Missouri, Columbia, MO 65211, USADepartment of Biomedical, Biological, and Chemical Engineering, University of Missouri, Columbia, MO 65211, USADepartment of Environmental and Civil Engineering, University of Missouri, Columbia, MO 65211, USADepartment of Biomedical, Biological, and Chemical Engineering, University of Missouri, Columbia, MO 65211, USAElectron Microscopy Core Center, University of Missouri, Columbia, MO 65211, USAThis study evaluated the effect of carbon nanofibers (CNFs) coated by aluminum oxide Al<sub>2</sub>O<sub>3</sub> as a reinforcement on compressive strength, frost resistance, and drying shrinkage of cement mortars. Three weight ratios of 0.125%, 0.25%, and 0.5% of Al<sub>2</sub>O<sub>3</sub>/CNFs and bare CNF cement mortars were compared with reference cement mortar samples. The reactive porous and high surface area layer of alumina induced the hydration reaction and promoted the production of well-distributed hydration gel. Derivative thermal analysis–differential thermogravimetric (TGA-DTG) and X-ray powder diffraction (XRD) characterization showed that Al<sub>2</sub>O<sub>3</sub>/CNFs reinforcement led to greater hydration gel production than bare CNFs. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were performed to study the coating and microstructure of the cement mortars evaluated in this paper. The results show that the optimum enhancement of the cement mortar properties was obtained at ratios of 0.125% for Al<sub>2</sub>O<sub>3</sub>/CNFs and 0.25% for CNFs. This enhancement was greater with Al<sub>2</sub>O<sub>3</sub>/CNFs-reinforced specimens in terms of high compressive strength, less compressive strength degradation after 150 cycles, and less drying shrinkage. The low use of the CNFs in Al<sub>2</sub>O<sub>3</sub>/CNFs samples indicates the coating is an economical and promising approach for improving the performance of cement mortars.https://www.mdpi.com/1996-1944/15/8/2768carbon nanofibersnanocoatingaluminadurability |
| spellingShingle | Huda Al Qader Ahmed M. Jasim Hani Salim Yangchuan Xing David Stalla Enhanced Mechanical and Durability Properties of Cement Mortar by Using Alumina Nanocoating on Carbon Nanofibers Materials carbon nanofibers nanocoating alumina durability |
| title | Enhanced Mechanical and Durability Properties of Cement Mortar by Using Alumina Nanocoating on Carbon Nanofibers |
| title_full | Enhanced Mechanical and Durability Properties of Cement Mortar by Using Alumina Nanocoating on Carbon Nanofibers |
| title_fullStr | Enhanced Mechanical and Durability Properties of Cement Mortar by Using Alumina Nanocoating on Carbon Nanofibers |
| title_full_unstemmed | Enhanced Mechanical and Durability Properties of Cement Mortar by Using Alumina Nanocoating on Carbon Nanofibers |
| title_short | Enhanced Mechanical and Durability Properties of Cement Mortar by Using Alumina Nanocoating on Carbon Nanofibers |
| title_sort | enhanced mechanical and durability properties of cement mortar by using alumina nanocoating on carbon nanofibers |
| topic | carbon nanofibers nanocoating alumina durability |
| url | https://www.mdpi.com/1996-1944/15/8/2768 |
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