Development of Multi-Scale Carbon Nanofiber and Nanotube-Based Cementitious Composites for Reliable Sensing of Tensile Stresses

Abstract

In this work, multi-scale cementitious composites containing short carbon fibers (CFs) and carbon nanofibers (CNFs)/multi-walled carbon nanotubes (MWCNTs) were studied for their tensile stress sensing properties. CF-based composites were prepared by mixing 0.25, 0.5 and 0.75 wt.% CFs (of cement) with water using magnetic stirring and Pluronic F-127 surfactant and adding the mixture to the cement paste. In multi-scale composites, CNFs/MWCNTs (0.1 and 0.15 wt.% of cement) were dispersed in water using Pluronic F-127 and ultrasonication and CFs were then added before mixing with the cement paste. All composites showed a reversible change in the electrical resistivity with tensile loading; the electrical resistivity increased and decreased with the increase and decrease in the tensile load/stress, respectively. Although CF-based composites showed the highest stress sensitivity among all specimens at 0.25% CF content, the fractional change in resistivity (FCR) did not show a linear correlation with the tensile load/stress. On the contrary, multi-scale composites containing CNFs (0.15% CNFs with 0.75% CFs) and MWCNTs (0.1% MWCNTs with 0.5% CFs) showed good stress sensitivity, along with a linear correlation between FCR and tensile load/stress. Stress sensitivities of 6.36 and 11.82%/MPa were obtained for the best CNF and MWCNT-based multi-scale composite sensors, respectively.

Colloidal Processing of Mn3O4-Carbon Nanotube Nanocomposite Electrodes for Supercapacitors

“…Colloidal methods are widely used for the fabrication of advanced nanomaterials and nanocomposites [ 1 , 2 , 3 ]. The use of surfactants for colloidal nanofabrication allows efficient control of particle size and prevention of their agglomeration [ 4 , 5 , 6 , 7 ]. Of particular interest is the use of surfactants for the fabrication of nanocomposite electrodes for energy storage in supercapacitors.…”

Advances and Applications of Carbon Nanotubes

“…In total, twenty-three articles are published on this Topic in the participating journals Nanomaterials, Applied Sciences, and Materials. The presented knowledge embraces numerical simulations [2,[5][6][7][8][9][10][11] and/or experimental data [1,[12][13][14][15][16][17][18][19][20][21][22][23].…”

“…A large set of new (nano)materials is under scrutiny, namely, silica-microsphere-supported N-doped CNT for electromagnetic wave absorption [13], low crystallinity CNT arrays as potential gas sensors [14], synthesis of tin dioxide/CNT nanonests for use in lithium-ion batteries [15], 3D CNT monoliths for controlled adsorption [16], and six different CNT yarns prepared by various spinning methods [17], among others [18,19]. Further developments were focused on materials for civil infrastructures such as sand-gel composites [20], cementitious composites [4,21], and ultra-high-performance concrete [23].…”