ABSTRACT
The oxidation of CO has attracted great interest in recent years due to its important role in enhancing the catalyst durability in fuel cells and solving the growing environmental problems caused by CO emissions. Consequently, the catalytic oxidation of CO at double non-noble metal atoms anchored C2N is investigated using density functional theory (DFT) computations. All the screened Ti@C2N and Ti2@C2N are thermodynamically stable based on their binding energy calculations. The electronic characteristics, the natural bond orbital analyses (NBO), Frontier orbital, statistical thermodynamics, projected densities of states (PDOS) characteristics, non-covalent interactions (NCI), and quantum theory of atoms in molecules (QTAIM) descriptors of these systems have been examined to analyze the interaction process. Our comparative study suggested that the newly predicted double-atom catalyst (Ti2@C2N) is highly active for CO oxidation, which is a useful guideline for further development. The calculated static first-order hyperpolarizability (ßo) illustrated that the double-atom catalyst under investigation can be considered a potential candidate for non-linear optical behavior and could be used for NLO applications. CO oxidation on Ti2@C2N along the Eley-Rideal (ER) mechanism with a low energy barrier of 0.16 eV, which is smaller than the maximum energy barrier (0.73 eV) of CO oxidation along the Langmuir-Hinshelwood (LH) mechanism. Consequently, the ER mechanism is more favorable both thermodynamically and dynamically. This work can provide useful insights and guidelines for future theoretical and experimental investigations to promote the design and development of highly effective and low-cost non-precious-metal Ti2@C2N nanocatalysts towards CO oxidation at ambient temperature.
Subject(s)
Electronics , Transition Elements , Catalysis , Oxidation-Reduction , Quantum Theory , ThermodynamicsABSTRACT
Context hydrazine compounds based on 1,3,5-triazine were synthesised and their molecular structures were characterised by elemental analysis, Electronic, IR and 1H NMR spectra. The spectral behaviour of the newly prepared compounds in organic solvents of different polarities was extensively studied and correlated to the molecular structure. In this study, 1,3,5-Triazine derivatives (L1, L6, L7, L8) have been subjected to theoretical studies using the Semi-empirical PM3 quantum chemical method. The physical-chemical properties of some Hydrazone derivatives are determined theoretically. The molecular geometry, the Highest Occupied Molecular Orbital (HOMO) - Lowest Unoccupied Molecular Orbital (LUMO) energy gap, molecular hardness (η), ionisation energy (IE), Electron affinity and total energy were analysed, and applications as biological effects were done.