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Inorganic two-dimensional semiconductor indium sulfide (In2S3) has recently attracted considerable attention as a buffer material in the field of thin-film photovoltaics, photo electrochemical cells and other energy-related applications. Compared with this growing interest, however, detailed characterizations of the commercial material are not done. The present investigation deals with the systematic investigation of the physical properties of powdered β-indium sulfide (In2S3). The crystalline structure, the composition, and the morphological properties of the samples were characterized using a range of techniques such as X-ray powder diffraction (XRD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). X-ray diffraction patterns revealed mixed peaks of In2S3 and In2O3 for the sample annealed at 400 °C. The In2O3 peaks were crystalline with a cubic phase with a (222) preferential orientation. These results were supported by the FTIR, and XPS studies. Thus, a significant correlation was established between the annealing temperature and the TEM images. The main conclusion of the paper opens the possibility of using In2S3 layers for solar cells.

This study investigated the effect of using calcium carbonate (CaCO3) nanoparticles on the microstructural properties, flexural strength and fracture toughness of ceramic nanomaterials. The flexural strength and fracture toughness were evaluated for CaCO3 nanoparticle contents of 1%, 2%, and 3% by weight of cement powder. The microstructural analyses from X-ray diffraction showed that nano-CaCO3 improved the microstructure of nanocomposites because it reduces the tricalcium silicate and dicalcium silicate peaks and increases the calcium silicate hydrate products. Moreover, the results showed that the nanocomposites with 1 wt% nano-CaCO3 exhibited the maximum flexural strength and fracture toughness compared to the other composites owing to the filler and nucleation effect of nano-CaCO3. In addition, nano-CaCO3 could resist the unstable micro-crack propagation in cement nanocomposites by filling the micro-cracks and voids. Future applications in synthesis or steel fiber-reinforced concrete or ceramic nanocomposites could benefit from the use of the analyses presented in this study.

Cement nanocomposites reinforced with hemp fabrics and calcined nanoclay (CNC) have been fabricated and investigated. The treated hemp fabric-reinforced cement composites and nanocomposites were subjected to 3 wetting and drying cycles and then tested at 56 and 236 days. The influences of CNC dispersion on the durability of these composites have been characterized in terms of porosity, flexural strength, stress-midspan deflection curves and microstructural observation of hemp surface. The microstructure of matrix was investigated using X-ray Diffraction. Results indicated that the CNC effectively mitigated the degradation of hemp fibre. The durability and the degradation resistance of hemp fibre enhanced due to the addition of CNC into the cement matrix and the optimum content of CNC was 1 wt.%. Keywords: Nanoclay-cement composites, Hemp fabric, Durability, Microstructure

Cement nanocomposites reinforced with hemp fabrics and calcined nanoclay (CNC) have been fabricated and investigated. CNC is prepared by heating nanoclay (Cloisite 30B) at 900°C for 2h. The influences of CNC dispersion on the mechanical properties and thermal properties of these composites have been characterized in terms of porosity, density, water absorption, flexural strength, fracture toughness, durability impact strength, and thermal stability. The microstructure is investigated using quantitative X-ray diffraction analysis and high-resolution transmission electron microscopy. The effects of alkali (NaOH) treatment of hemp fabric on the mechanical properties of hemp fabric-reinforced cement composites with different fabric contents of 4.5, 5.7, 6.9, and 8.1 wt% are also investigated. Results show that the optimum hemp fabric content is 6.9 wt% (i.e., six fabric layers). Results also indicated that physical, mechanical, and thermal properties enhanced because of the addition of CNC into the cement matrix and the optimum content of CNC was 1 wt%. The treated hemp fabric–reinforced nanocomposites containing 1 wt% CNC exhibited the highest flexural strength, fracture toughness, impact strength, and thermal stability than their counterparts and good fiber–matrix interface. Results also indicated that the CNC effectively mitigated the degradation of hemp fiber. The durability and the degradation resistance of hemp fiber were enhanced due to the addition of CNC into the cement matrix and the optimum content of CNC was 1 wt%. This environmentally friendly nanocomposite can be used for various construction applications such as ceilings and roofs.

The influence of calcined nanoclay (CNC) and chemical treatment on the microstructure and mechanical properties of treated hemp fabric-reinforced cement nanocomposites has been investigated. The optimum hemp fabric content for these nanocomposites is 6.9 wt% (i.e. 6 fabric layers). Alkali-treated hemp fabric-reinforced cement composites exhibit the highest flexural strength when compared to their non-treated counterparts. In addition, mechanical properties are improved as a result of CNC addition. An optimum replacement of ordinary Portland cement with 1 wt% CNC is observed through reduced porosity and increased density, flexural strength and fracture toughness in treated hemp fabric-reinforced nanocomposite. It is shown that CNC behaves not only as a filler to improve the microstructure, but also as the activator to facilitate the pozzolanic reaction and thus improved the adhesion between the treated hemp fabric and the matrix.

Cement nanocomposites reinforced with hemp fabrics and calcined nanoclay (CNC) have been fabricated and investigated. CNC is prepared by heating nanoclay (Cloisite 30B) at 900 °C for 2 h. The influences of CNC dispersion on the mechanical properties and thermal properties of these composites have been characterized in terms of porosity, density, water absorption, flexural strength, fracture toughness, impact strength and thermal stability. The microstructure is investigated using Quantitative X-ray Diffraction Analysis (QXDA) and High Resolution Transmission Electron Microscopy (HRTEM). The effects of alkali (NaOH) treatment of hemp fabric on the mechanical properties of hemp fabric-reinforced cement composites with different fabric contents of 4.5, 5.7, 6.9 and 8.1 wt% are also investigated. Results show that the optimum hemp fabric content is 6.9 wt% (i.e. 6 fabric layers). Results also indicated that physical, mechanical and thermal properties were enhanced due to the addition of CNC into the cement matrix and the optimum content of CNC was 1 wt%. The treated hemp fabric-reinforced nanocomposites containing 1 wt% CNC exhibited the highest flexural strength, fracture toughness, impact strength and thermal stability by virtue of good fibre–matrix interface. This environmentally friendly nanocomposite can be used for various construction applications such as ceilings and roofs.

The influence of nanoclay (NC) and calcined nanoclay (CNC) on the mechanical and thermal properties of cement nano-composites presented. Calcined nanoclay is prepared by heating nanoclay (Cloisite 30B) at 900 °C for 2 h. Characterisation of microstructure is investigated using Quantitative X-ray Diffraction Analysis (QXDA) and High Resolution Transmission Electron Microscopy (HRTEM). Estimation of Ca(OH)2 content in the cement nanocomposite is studied by the combination of QXDA and thermogravimetry analysis (TGA) techniques. Results showed that the mechanical and thermal properties of the cement nanocomposites are improved as a result of NC and CNC addition. An optimum replacement of ordinary Portland cement with 1 wt% CNC is observed through reduced porosity and water absorption as well as increased density, compressive strength, flexural strength, fracture toughness, impact strength, hardness and thermal stability of cement nanocomposites. The microstructural analyses from QXRA and SEM indicate that the CNC acted not only as a filler to improve the microstructure, but also as the activator to support the pozzolanic reaction. Cost-benefit analysis indicates that nanoparticles are expensive but from economic point of view nanoclay is used in very small amount (i.e. 1 wt. %) in cementitious materials. As a result nanoclay does not add any significant cost but improves the mechanical properties significantly.

In the construction industry, several types of nanomaterials have been incorporated into concretes or cement based materials such as nano-SiO2, nano-Al2O3, nano-Fe2O3, nano-ZnO2, nano-MgO, nano-CaCO3, nano-TiO2, carbon nanotubes, nano-metakaolin and nano-ZrO2 in order to improve the durability and mechanical properties of concrete and Portland cement matrix.

This chapter presents the micro-structural characterisation, physical, mechanical and thermal properties of nanoclay-cement nanocomposites fabricated and tested at 56 days. The influence of nanoclay on properties of hemp fabric-reinforced cement composites is also presented in this chapter. Two layers of hemp fabric (HF) were used and the total amount of hemp fabric in each specimen was about 2.5 wt%.

Recently, natural fibres are gaining increasing popularity to develop ‘environmental-friendly construction materials’ as alternative to synthetic fibres in fibre-reinforced concrete. Natural and cellulose fibres have been used in polymer and cement matrices to improve their tensile/flexural strength and fracture resistance properties. They are cheaper, biodegradable and lighter than synthetic fibres. Some examples of natural fibres are: sisal, flax, hemp, bamboo and others.

This chapter presents the durability of hemp fibre reinforced cement composites by combining both methods e.g. modification of fibre surfaces using NaOH solution and the cement matrix by adding calcined nano clay. The effect of calcined nanoclay (CNC) on the durability properties of treated hemp fabric-reinforced cement composite is studied. The durability of the treated hemp fabric-reinforced cement composites and nanocomposites is discussed based on the porosity and flexural strength obtained at 56 days and 236 days. Thus eight series of mixes are considered in this study. The first series is control matrix termed as “C” and consisted of 100% OPC. The second, third and fourth series are similar to the first series in every aspect except the partial replacement of OPC by 1, 2 and 3 wt% of CNC, respectively. These series are termed as CNCC1, CNCC2 and CNCC3, respectively. In fifth series the control OPC matrix is reinforced by NaOH treated 6 layers of HF and is termed as 6THFRC. The sixth, seventh and eighth series are similar to fifth series in every aspect except the partial replacement of OPC by 1, 2 and 3 wt% of CNC, respectively. These series are termed as 6THFRC-CNCC1, 6THFRC-CNCC2 and 6THFRC-CNCC3, respectively. A constant water/binder ratio of 0.485 is considered in all mixes.

Cement eco-nanocomposites reinforced with hemp fabric (HF) and nanoclay platelets (Cloisite 30B) are fabricated and investigated in terms of X-ray diffraction, scanning electron microscopy, physical and mechanical properties. Results indicated that the mechanical properties generally increased as a result of the addition of nanoclay into the cement matrix with HF. An optimum replacement of ordinary Portland cement with 1 wt% nanoclay decreased the porosity and also significantly increased the density, flexural strength and fracture toughness of HF-reinforced nanocomposite. The microstructural results indicate that the nanoclay behaves not only as a filler to improve the microstructure, but also as an activator to promote the pozzolanic reaction and thus improved the adhesion with hemp fabric. The failure micromechanisms and energy dissipative processes in HF-reinforced cement composite and HF-reinforced nanocomposite are discussed in terms of microstructural observations. These cement eco-nanocomposites can provide new insights for the development of new ‘environmental-friendly nanomaterials’ for building applications such as the construction of sandwich panels, ceilings and roofs.

Cement eco-nanocomposites reinforced with hemp fabric (HF) and nanoclay platelets (Cloisite30B) are fabricated and investigated in terms of XRD, SEM, physical and mechanical properties. Results indicated that the mechanical properties generally increased as a result of the addition of nanoclay into the cement matrix with and without HF. An optimum replacement of ordinary Portland cement by 1 wt% nanoclay is concluded from the current work. It is found that, 1 wt% nanoclay decreases the porosity and also significantly increases the density, flexural strength and fracture toughness of cement composite and HF reinforced nanocomposite. The microstructural analysis results indicate that the nanoclay behaves not only as a filler to improve microstructure, but also as an activator to promote pozzolanic reaction which modified cement matrix and improved the hemp fabric-matrix adhesion. The failure micromechanisms and energy dissipative processes in HF reinforced cement composite and nanocomposite are discussed in terms of microstructural observations.

The influence of nanoclay on thermal and mechanical properties of hemp fabric-reinforced cement composite is presented in this paper. Results indicate that these properties are improved as a result of nanoclay addition. An optimum replacement of ordinary Portland cement with 1 wt% nanoclay is observed through improved thermal stability, reduced porosity and water absorption as well as increased density, flexural strength, fracture toughness and impact strength of hemp fabric-reinforced nanocomposite. The microstructural analyses indicate that the nanoclay behaves not only as a filler to improve the microstructure but also as an activator to promote the pozzolanic reaction and thus improve the adhesion between hemp fabric and nanomatrix.

influence of calcined nanoclay (CNC) on the porosity and fracture toughness of treated hemp fabric-reinforced cement nanocomposites is presented in this paper. Characterisation of microstructure is investigated using Quantitative X-ray Diffraction Analysis (QXDA) and High Resolution Transmission Electron Microscopy (HRTEM). An optimum replacement of ordinary Portland cement with 1 wt% CNC is observed through reduced porosity and increased fracture toughness of treated hemp fabric-reinforced nanocomposite. The microstructural analysis indicates that the CNC affect not only as a filler to improve the microstructure, but also as the activator to support the pozzolanic reaction and thus improved the adhesion between the treated hemp fabric and the matrix. Cost-benefit analysis indicates the benefit of such cement eco-nanocomposites to develop new environmentally friendly nanomaterials and it can be used for various construction applications such as, ceilings and roofs.