Effectiveness of using nanoparticles in green composites: A scientometric analysis of fresh, mechanical, durability, and microstructural features

Geopolymer (GPL) nanocomposites are relatively new environment-friendly composite materials that can be employed as a substitute for Portland cement in the construction industry to minimize the carbon emissions of cement production. Less energy consumption and reduced carbon footprint compared with Portland cement are the main advantages of producing GPL. During the last few decades, nanotechnology is in the spotlight of advanced research with valuable applications and innovative science. The applications of various kinds of nanoparticles (NPL) in improving the engineering features of GPL are increasing day by day. A large number of research investigations are available in the literature that explores the mechanical, durability, and microstructural features of GPL incorporated with NPL. The present study has endeavored to examine and compare the influence of adding various kinds of NPL to GPL composites. Previous literature studies from various search engines were targeted to find the articles showing the effect of various NPL including different aspects of GPL pastes, conventional GPL concrete composites, recycled aggregate GPL concrete, high-strength GPL concrete, fiber-reinforced GPL, self-compaction GPL concrete, GPL mortars, and light-weight GPL concrete. Various fresh features, mechanical performance, durability behavior, and microstructural features of GPL mortar and concrete were evaluated and compared. Furthermore, the mechanism of working of various kinds of NPL in GPL composites was investigated and their effectiveness on the various features of GPL was studied. The environmental aspects, limitations in applications, and future challenges of using NPL in GPL composites were also discussed. This study concluded that the incorporation of NPL in GPL and concrete composites are a promising alternative for Portland cement to produce a high-performing GPL mix for the construction industry. The NPL incorporation substantially improves the strength, durability, and microstructural features of GPL by developing C-A-S-H, C-SH, and N-A-S-H gels that effectively fill the internal micro- and nano-voids to produce a densified matrix.