Influence of Exfoliated G-c3n4 on the Mechanical Properties of Structural Mortars

Abstract This study intends to develop a new mortar material with improving microstructural properties through the addition of nanomaterials in its composition. Among the nanomaterials with interesting features, graphitic carbon nitride (g-C3N4) stands out for having a graphene-like carbon-based structure, in addition to exhibiting high chemical/thermal stability, and excellent electronic and optical properties. The present study evaluated the influence of exfoliated g-C3N4 addition, with 0.25%, 0.50%, and 1.00% by weight of anhydrous cement, on the physical and mechanical properties of structural mortars. The microstructure of the exfoliated g-C3N4 was characterized by transmission electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. Regarding the characterization of the mortars, the physical and mechanical properties were evaluated by flow table test, porosity and density measurements, SEM microscopy, and flexural and compressive strength tests. When the dosage of g-C3N4 nanosheets was 1.0% by weight of cement, the compressive and flexural tensile strengths at 28 days increased by 16% and 18%, respectively. At the same time, the addition of the nanomaterials also seems to have reduced the workability and slightly increased the total porosity. When compared with regular cement mortar, despite negatively affecting the compaction of the structure, it reveals that the exfoliated g-C3N4 addition could act as a reinforcing agent, improving the engineering performance of the cement composites making possible the production of lighter and stronger structures.