Research On The Inhibition Mechanism Of Heterocyclic Organic Inhibitors And The Properties Of Several Novel Semiconductor Materials

Generally, it’s valuable and important to explore ways to avoid equipment corrosion in the area of chemistry and chemical engineering. The semiconductor films formed on the metal surface can be seen as a protective layer to prevent metal corrosion, so studies on the geometric, electronic, and optical properties of these semiconductor materials are very necessary. Besides, among numerous corrosion prevention measures, corrosion inhibition possesses advantages of economy, high-efficiency, and facile- feasibility, and has been widely applied in various fiel. It has become a hot topic in the research of salt & petrochemical.Based on the above background, this study contains two primary parts. The first part is the research on the corrosion inhibition mechanism of several heterocyclic organic molecules for copper and carton steel. The second part is the calculation of physical characteristics for some novel semiconductor materials.In the first part of the study, mainly including the following respects,① The molecular reactivity of 4-chloro- acetophenone-O-1’-(1’.3’.4’-triazolyl)- methene-oxime(CATM), 4-fluoro-acetophenone-O-1’-(1’.3’.4’-triazolyl)-metheneoxime(FATM), and 3,4-dichloro-acetophenone-O-1’-(1’.3’.4’-triazolyl)-methene oxime(DATM) was investigated using density functional theory(DFT). Quantum chemical parameters such as the highest occupied molecular orbital energy, the lowest unoccupied molecular orbital energy, energy gap, dipole moment, and the fraction of electrons transferred, were calculated. Quantitative structure activity relationship approach has been used, and a composite index of above-mentioned descriptors was performed to characterize the inhibition performance of the studied molecules. Furthermore, Monte Carlo simulation studies were applied to search for the best configurational space of iron/triazole derivative system.② Inhibition effect of 2-aminothiazole on mild steel corrosion in 0.5 M H2SO4 and 1.0 M HCl media has been studied using various electrochemical techniques, viz., electrochemical impedance spectroscopy, linear polarization resistance method, and Tafel polarization. The docking way between the 2-aminothiazole molecule and iron atoms was investigated by DFT, quantum theory of atoms in molecules(QTAIM), and molecular dynamics(MD) simulation.③ The adsorption of thiophene, pyrrole, and furan molecules on Fe(110) surface was studied using different functionals as well as conductor-like screening model for real solvents. A empirical law was confirmed, i.e., the corrosion inhibition efficiency of the homologous series of organic substances differing only in the heteroatom is usually in the following sequence: S > N > O.④ Using quantum chemical and molecular dynamics approaches, the corrosion inhibition mechanism of Cu/HNO3 system in the presence of three triazole derivatives, i.e., 3-amino-1,2,4-triazole(ATA), 3,5-diamino-1,2,4-triazole(DAT), and 4-amino-3- hydrazino-5-mercapto-1,2,4-triazole(AHMT), was investigated. The interactions between inhibitors and copper substrates were evaluated using density functional theory with and without dispersion energy correction for describing van der Waals. The diffusion behavior of corrosive particle(H3O+) in membranes formed by three triazole compounds was investeigated with MD simulation. A reasonable adsorption and inhibition mechanism was proposed.⑤ The structural stability, electronic, elastic, and optical properties of the Cd X(X =S/Se/Te), Cd Rh2O4, β-Ag MO2(M=Al/Ga) have been investigated using the first- principle approach. The paper explores the band structure, density of states, and electron density difference. The conventional parameters, such as cohesive energy, band gap, debye temperature, anisotropy coefficient, refractive index, dielectric constant, are obtained accordingly and compared with other calculations and experimental measurements.