Synthesis of Carbon Nanotubes and Nanofibers on Silica and Cement Matrix Materials

Abstract

In order to create strong composite materials, a good dispersion of carbon nanotubes (CNTs) and nanofibers (CNFs) in a matrix material must be obtained. We proposed a simple method of growing the desirable carbon nanomaterial directly on the surface of matrix particles. CNTs and CNFs were synthesised on the surface of model object, silica fume particles impregnated by iron salt, and directly on pristine cement particles, naturally containing iron oxide. Acetylene was successfully utilised as a carbon source in the temperature range from 550 to750∘C. 5–10 walled CNTs with diameters of 10–15 nm at600∘Cand 12–20 nm at 750∘Cwere synthesised on silica particles. In case of cement particles, mainly CNFs with a diameter of around 30 nm were grown. It was shown that high temperatures caused chemical and physical transformation of cement particles.

A quantitative method for analysing the dispersion of carbon nanotubes in cement composite materials

“…Numerous methods have been applied for the purpose of better dispersion, such as physical dispersion methods, chemical dispersion methods, the combination of physical and chemical methods (Han et al, 2011;Raki et al, 2010;Sun et al, 2013) and growing CNTs in situ on the cement/mineral admixture particles (Cwirzen et al, 2009;Hlavacek et al, 2011;Hlavacek and Smilauer, 2012;Mudimela et al, 2009;Nasibulin et al, 2007Nasibulin et al, , 2009Nasibulin et al, , 2013Nasibulina et al, 2010Nasibulina et al, , 2012.…”

Nanobioceramic Composites: A Study of Mechanical, Morphological, and Thermal Properties

“…Carbon materials have a naturally high electrical conductivity and low cost, high surface area, porosity, and formability, and possess good chemical and electrochemical resistivity (Mudimela et al 2009). Carbon black is a form of amorphous carbon that has an extremely high surface area to volume ratio.…”

“…Carbon black is a form of amorphous carbon that has an extremely high surface area to volume ratio. As such, it is one of the first nano-materials to be commonly used (Mudimela et al 2009). With the novel discovery of carbon nanotubes (CNTs) and nanofillers (CNFs) material, having unique geometrical structure, stable mechanical and chemical properties, it has attracted wide scale attention in many sectors (Mudimela et al 2009).…”

“…As such, it is one of the first nano-materials to be commonly used (Mudimela et al 2009). With the novel discovery of carbon nanotubes (CNTs) and nanofillers (CNFs) material, having unique geometrical structure, stable mechanical and chemical properties, it has attracted wide scale attention in many sectors (Mudimela et al 2009). Predominantly, carbon black is used as a pigment and for reinforcement in rubber and plastic products.…”

Performance of carbon nanofiber-cement composites subjected to accelerated decalcification

“…CNFs possess a number of unique properties, such as high specific strength, chemical resistance, and electrical and thermal conductivity, making them excellent candidates for nanoscale reinforcement in cement composites [3,4]. While most studies to date have been conducted to examine the direct structural, mechanical, and electrical properties provided by the CNFs [5][6][7], the long-term chemical and structural stability of these materials in response to severe conditions such as decalcifying environments and the potential impact of the CNF dispersion on the chemo-mechanical behavior of CNF-cement composites has received little attention. This paper reports on how microstructural alteration of the cement paste due to decalcification affects the nano-scale reinforcement ability of the CNFs, and in turn, the macro-scale properties of the material.…”