New Concept on Photocatalytic Degradation of Thiophene Derivatives: Experimental and DFT Studies

Abstract

In this study, the photocatalytic degradation of seven sulfur compounds (2-methylthiophene, 3-methylthiophene, 2-phenylthiophene, 3-phenylthiophene, 2,5-diphenylthiophene, 2-(2-thienyl) pyridine, and 2-(3-thienyl) pyridine in semiaqueous medium are compared to thiophene. The apparent-reaction-rate constant (k) is found to decrease in the following order: 2From the data obtained by UV light absorption (λ max ) measurements and electronic structure calculations (frontier orbitals energy, global hardness, and global softness), the kinetic parameters of the reaction have been determined. Among the studied compounds, thiophene with a high λ max and low calculated LUMO−HOMO gap energy has showed higher activity under UV irradiation. Interestingly, a lower activity is observed with low λ max and high LUMO−HOMO gap energy. This demonstrates, for the first time, that the reactivity depends essentially on the thermodynamic stability of the sulfur compound rather than on the nature or the position of the substituent on the ring.

Study of N‐methyl‐5‐nitroindazolylacrylonitriles as a Function of Quantum Parameters Employing Density Function Theory Methods: Comparative Theoretical Study and Nonlinear Optical Properties

“…When the maximal absorption wavelength of UV light is high, the propensity of thiophene derivatives to be swiftly oxidized can be viewed as a fundamental parameter to predict their reactivity. This is a novel method for determining their kinetics that can replace expensive and time‐consuming testing [28] . The calculated excitation energy (E), absorption wavelengths (λ), and oscillatory forces (ƒ) are shown in Table 6.…”

“…The CDFT reactivity indices were calculated using the equations given in reference [22a] . NMR were simulated by using Gauge‐Independent Atomic Orbital (GIAO) calculations [28] . All chemical and physical properties of indazoles 2 a – l were calculated at theB3LYP/6‐311G(d,p) computational level.…”

“…This is a novel method for determining their kinetics that can expensive and time-consuming testing. [28] The calculated excitation energy (E), absorption wavelengths (λ), and oscillatory forces (ƒ) are shown in Table 6. Figure 5 shows the hypothetical UV-Vis spectrum of 2 a.…”

Elucidating the Aromatic Properties of Covalent Organic Frameworks Surface for Enhanced Polar Solvent Adsorption

“…The optimized structures were utilized for frequency, NMR and natural bond orbital (NBO) calculations. Specifically, the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) (E HL ) [ 20 ], hardness (η) [ 21 ], softness ( S ) [ 22 ], point groups [ 23 ] and geometric parameters for measuring harmonic oscillator model of aromaticity (HOMA) [ 24 ] were calculated. All detailed information for measuring HOMA is available in Section SI.1.2.…”

One-pot synthesis of Mn3O4-coupled Ag2WO4 nanocomposite photocatalyst for enhanced photooxidative desulfurization of thiophene under visible light irradiation

“…The exploration for a competitive way for ThP elimination started in a boundless concern. The oxidative desulfurization process employing photocatalysis is one of the most talented and clean systems for environmental remediation compared to other counterparts (Kêdra-Królik et al 2011;Zeng et al 2017;Li et al 2019;Zhang et al 2019a;Lin et al 2012;Djouambi et al 2018). Nanocomposites consisting of nanoparticles are employed to develop novel environment-friendly chemical mechanical polishing slurries (Zhang et al2016a(Zhang et al , b, 2018(Zhang et al , 2019b, which is used to polish high-performance substrates used in semiconductor and microelectronics industries.…”