Enhancing of Corrosion Protection of Steel Rebar in Concrete Using TiO2 Nanoparticles as Additive

Abstract

Nanomaterials became targeted materials for many important applications due to its huge surface area and quantum confinement effects. In this work TiO2 nanoparticles (30nm) were used as additive to enhance the corrosion protection of steel rebar in artificial concrete solution (Ca(OH)2 (2g), KOH (22.44mg), NaOH (8mg) in 1L of distilled water) against saline environment (3.5%NaCl) at four temperatures; 20, 30, 40, and 50á´¼C. Three different concentrations of TiO2 NPs were used namely; 1, 3, and 5% by weight. The corrosion parameters and pitting probability were followed using Tafel and cyclic polarization plots respectively. Protection enhancement was recorded at all TiO2 percent used and efficiencies of 75-86% were achieved. Using TiO2 NPs reduces but not diminished the pitting hysterias loop area. The results supported by surface morphology examination using atomic force microscope (AFM).

Enhancement of corrosion protection of metal carbon steel C45 and stainless steel 316 by using inhibitor (Schiff base) in sea water

“…Tafel plot reveals that Ecorr for carbon steel or stainless steel in the presence of the inhibitors (50 ml of inhibitor was added) shifts to a higher (noble) position compared with blank solution, which means the protection works as anodic protection. The inhibition efficiency (%IE) was calculated by the following Eq.1 5 .…”

“…The values of Δ𝑆 * for in the presence and absence of the inhibitor are negative, this means that the activated complex, which is the ratelimiting step of the reaction, represents an association rather than a dissociation, this indicates a decrease in disorder taking place by going from the reactants to the activated complex 10 . The values of activation Gibbs free (∆G*) energies take positive values and most of them change slightly with increasing temperature, and this indicates that the activated complex is unstable and the probability of its formation decreases with increasing temperature, it also describes that the process is non-spontaneous one for transition reaction 5 .…”

“…Recently, nanomaterials have been used as a coating material on metal surfaces because of the unique properties that distinguish them from other materials. The most important of these materials are TiO2, ZnO, Al2O3, ZrO2…etc [3][4][5] , nanopolymers [6][7][8] , carbon nanomaterials (as reduced graphene oxide, graphene, and carbon nanotubes) [9][10][11][12] , drugs [13][14][15][16] , and environmentally friendly materials 17 all of which are reported. The second method that is used to reduce corrosion is the use of the so-called corrosion inhibitors 18 , which are chemical compounds, especially organic compounds (drugs or ligands; Especially ligands that contain nitrogen atoms [19][20][21] , such as Schiff bases [22][23][24][25] or other ligands [26][27][28][29] ) or nanoparticles 30 , that are added in small concentrations to the corrosion medium, they reduce corrosion by decreasing cathodic reduction or anodic oxidation, or both, by making a film on the metal surface.…”

Factorial Mixture Design for Properties Optimization and Modeling of Concrete Composites Incorporated with Acetates as Admixtures

“…Among those additives are nanoparticles including nano-silica (nano-SiO 2 ), nano-alumina (nano-Al 2 O 3 ), nano-ferric oxide (nano-Fe 2 O 3 ), nano-titanium oxide (nano-TiO 2 ), carbon nanotubes (CNTs), graphene and graphene oxide [2][3][4]. Moreover, nanopolymers were found to participate in self-healing mechanisms [5,6], as well as rewarding an improved product layer on the steel surface and calcium content in the bulk matrix [7].…”

The use of Nanomaterials in the construction sector: A literary review

“…Currently, with the implementation of nanoparticles as an additional material in the designs of concrete mixtures, better results have been obtained in the fresh properties of concrete, since it improves its mechanical characteristics, in addition to positively influencing the increase in durability [4]. Now, in order to 102 know the current advances in this field, studies on the influence of nanomaterials in different areas of the construction industry have been compiled [5].…”