Trends in Nanoscopy in Materials Research: Nano-Scale Microscopic Characterization of Cements

Introduction

Nanotechnology, a multidisciplinary research area of the current science and technology which includes material science, biological science, organic chemistry, molecular biology, surface science, micro fabrication and so on (R. Saini, S. Saini, & Sharma, 2010). It is become essential to adopt new tactics of making things through understanding and control over the fundamental building blocks (i.e. atoms, molecules and nanostructures) of all physical things. Over the few decades many researchers have shown their research interests on nano materials and are investing their time, skill and knowledge with a view to providing a new dimension in modern science and technology for the betterment of the world. Nano particles are typically smaller than large biological molecules such as enzymes, receptors, and antibodies. Being hundred to ten thousand times smaller than human cell, nanoparticles can offer novel interactions with biomolecules both on the surface of and inside the cells which may revolutionize cancer diagnosis and treatment (Cai, Gao, Hong, & Sun, 2008). The well-studied nanoparticles include quantum dots (Cai, Hsu, Li, & Chen, 2007; Cai et al., 2006), carbon nanotubes (Liu et al., 2006), paramagnetic nanoparticles (Thorek, Chen, Czupryna, & Tsourkas, 2006), liposomes (Park, Benz, & Martin, 2004), gold nanoparticles (Huang, Jain, I. H. El-Sayed, & M. A. El-Sayed, 2007), and many others (Grodzinski, Silver, & Molnar, 2006).

Nanotechnology based application in construction related technology is still very insignificant. Following after evolving nanotechnology applications in biomedical and electronic industries, the construction industry recently started seeking out a way to advance conventional construction materials using a variety of nanomaterials. Several nanomaterials can enhance fundamental characteristics of construction materials such as strength, durability, and thermal properties and perform as key sensing components to monitor structural safety and health. Despite the current relatively high cost of nanostructured products, their use in construction materials is likely to increase because of imparting highly valuable properties at relatively low additive ratios in nanostructured materials.

A range of nanomaterials can be incorporated for favorable applications in construction that encompass superior structural properties, functional paints and coatings, and high-resolution sensing/actuating devices. Carbon nanotubes (CNTs) can extra ordinarily enhance mechanical properties by bonding concrete mixtures (i.e. cementitious agents and concrete aggregates), reduce their fragility, prevent crack propagation and as well as improve their thermal properties (Lee, Mahendra, & Alvarez, 2010). Nanoparticles (e.g. SiO₂, TiO₂ and Fe₂O₃) can penetrate nano- or micropores that developed during cement hydration of concrete (Becher, 1991). Addition of magnetic nickel nanoparticles during concrete formation increases the compressive strength by over 15% as the magnetic interaction enhances the mechanical properties of cement mortars. Copper nanoparticles (NPs) mitigate the surface roughness of steel to promote the weldability and render the steel surface corrosion-resistant (Becher, 1991).

However, a little commercial activity has started to emerge and some nano-based materials are now adopted by the construction industry. There seems to be a lack of consciousness of nanotechnology among construction professionals (Zhu, Bartos, & Porro, 2004). To fix this skepticism, integrated actions are required for focused R&D for appropriate knowledge transfer in construction industry. Even minor developments in materials and practices could bring large accumulated benefits. The maximum impact is expected to come from enhancement in performance of materials with much improved energy efficiency, sustainability and adaptability to changing environment with nanotechnological development (Campillo, Dolado, & Porro, 2004).