Akademik Veri Yönetim Sistemi
11. International Drug Chemistry Conference, Antalya, Türkiye, 9 - 12 Mart 2023, ss.59
Abstract
In this study, the effects of plant-based α-pinene (C10 H16, 3.5 ml/L, α-Pi) and citric acid (H3C6H5O7·2H2O, 1mM, CA) on dental cp-Ti in artificial oral solutions were investigated through electrochemical methods and theoretical (DFT/PBEPBE) calculations. Electrochemical techniques such as open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and current-potential change (Tafel) were used. DFT calculations were investigated using the PBEPBE method on the Gaussian 09W with 6-311G(d,p) basis set. Results of the Tafel method showed that α-Pi shifted the corrosion potential in the anodic direction by approximately 20 mV compared to CA. When both components (α-PiCA) were present, the potential shifted by 160 mV more significantly increasing the polarization resistance to 254 kΩ cm2 (77%). Therefore, the corrosion rate of the material decreased from 0.74 μA cm-2 to 0.18
μA cm-2. The α-PiCA was able to prevent corrosion (76%) by acting as an anodic inhibitor. According to the experimental data, a synergistic effect between α-Pi and CA was observed, and TiO2 formation supported by the α-Pi. DFT calculations for α-Pi HOMO and LUMO energies, maximum wavelength (¼max), chemical hardness (ղ), softness (S) and electrophilicity (ω) were also performed. Since the electron density is on the oxygen atoms in the interior of the cp-Ti atoms, it is open to the effects that may come from the external environment (Figure 1a) (1-2). According to the experimental data, this gap on cp-Ti was closed by α-PiCA. The synergistic effect resulted in the reduction of electron density on cp-Titanium by α-pinene (Fig. 1b). α-pinene adsorbed on cp-Ti voluntarily, resulting in an energy release of 24,157 kcal/mol. As a result, the α-Pi determined to be a strong electrophile (ω=1.667 eV), ¼max obtained 212.41 nm and corrosion of cp-Ti significantly prevented by interconnecting α-Pi and cp-Ti with the help of both experimental and theoretical calculations.