This article presents the effect of LaSrCoO3, oxides commonly known as LSCO nanomaterials, on rheological, mechanical and microstructural properties of self‐compacting concrete (SCC). LSCO nanomaterials contents of 1–4 wt% are considered in this study. Compressive, flexural and split tensile strengths of SCC mixes are evaluated at curing ages of 7, 28, and 90 days. The effect of LSCO nanomaterials on the microstructures of above concretes is also evaluated using Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, thermogravimetric analysis techniques, Williamson–Hall equation, and X‐Powder software. Results show that workability of SCC mixes decrease with increase in LSCO nanomaterials. Increases are observed in compressive, flexural and split tensile strengths in SCC mixes when LSCO nanomaterials contents increase up to 2 wt%, followed by a decreasing trend which indicate 2 wt% as being the optimum amount. The microstructural analysis by means of various techniques also revels compact microstructure of cement matrix in SCC mixes containing 2 wt% LSCO nanomaterials, confirming the results of mechanical properties.

Titania nanoparticles are intensely studied for photodegradation applications. Control of nanoscale morphology and microstructural properties of these materials is critical for photocatalytic performance. Uniform anatase-type TiO2 nanoparticles were prepared by the sol-gel process using titanium isopropoxide as precursor. Controlled annealing up to 400 °C established crystallization and particle size ranging between 20 and 30 nm. Detailed thermal examination reveals that anatase phase transformation into rutile is affected by the annealing temperature and by the initial particle size. The anatase to rutile phase transformation occurs in the nanoparticles at 550 °C. The Total Reflection X-ray Fluorescence (TXRF) study of the anatase nanoparticles shows a shift towards higher energy in the Ka Ti line of 10 eV, related to structural defects. These features were discussed in the photocatalytic behavior of several cement-based materials modified with the so-prepared anatase nanoparticles. The photocatalytic activity of the anatase-type TiO2/cement mortar system is evaluated from the degradation of Methylene Blue (MB) under UV irradiation, monitored through the absorbance at 665 nm. The results show that the photocatalytic composites exhibit up to 76.6% degradation efficiency. Mechanical testing of the nano-TiO2 modified cementitious composites evinces a moderate reinforcement of the strength properties at long ages.

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