Unveiling the role of dopants in boosting CuS supercapacitor performance: insights from first-principles calculations.

Transition metal sulfides have become famous in high energy density supercapacitor materials owing to their rich redox and high conductivity. While their development has achieved a breakthrough in terms of capacitance, there is little knowledge from the theoretical perspective on how dopants play a role in enhancing their capacitances. In this work, pseudocapacitance and quantum capacitance were evaluated through first-principles calculation to describe their role in transition metal sulfide, which here is represented by copper sulfide (CuS).

Theoretical Investigation of the Green-Synthesized Carbon-Based Nanomaterial Potential as Inhibitors of ACE2 for Blocking SARS-CoV-2 Binding.

Since the emergence of SARS-CoV-2 in 2020, the world has faced a global pandemic, emphasizing the urgent need for effective treatments to combat COVID-19. This study explores the use of green-synthesized carbon-based nanomaterials as potential inhibitors of ACE2, a critical receptor for SARS-CoV-2 entry into host cells. Specifically, the study examines four carbon-based nanomaterials, namely, CD1, CD2, CD3, and CD4 in amino, graphitic, pyridinic, and pyrrolic forms, respectively, synthesized from curcumin, to investigate their binding affinity with ACE2.

Role of Intrinsic Points Defects on the Electronic Structure of Metal-Insulator Transition -FeS.

Hexagonal iron sulfide (h-FeS) offers huge potential in the development of metal-insulator transition devices. A stoichiometric h-FeS is hard to obtain from its natural iron deficiency. The effect of this iron deficiency on the electronic properties is still obscure.

Multi-scale Simulation of Equilibrium Step Fluctuations on Cu(111) Surfaces.

Understanding the nature of active sites is a non-trivial task, especially when the catalyst is sensitively affected by chemical reactions and environmental conditions. The challenge lies on capturing explicitly the dynamics of catalyst evolution during reactions. Despite the complexity of catalyst reconstruction, we can untangle them into several elementary processes, of which surface diffusion is of prime importance.

Vibration-driven reaction of CO on Cu surfaces via Eley-Rideal-type mechanism.

Understanding gas-surface reaction dynamics, such as the rupture and formation of bonds in vibrationally and translationally excited ('hot') molecules, is important to provide mechanistic insight into heterogeneous catalytic processes. Although it has been established that such excitation can affect the reactions occurring via dissociative mechanisms, for associative mechanisms-in which the gas-phase reactant collides directly with a surface-adsorbed species-only translational excitation has been observed to affect reactivity. Here we report a bond-formation reaction that is driven by the vibrational energy of reactant molecules and occurs via an (associative) Eley-Rideal-type mechanism, in which the reaction takes place in a single collision.

Van der Waals density functional study of formic acid adsorption and decomposition on Cu(111).

We present a density functional theory study on the adsorption and decomposition mechanisms of monomeric formic acid (HCOOH) on a Cu(111) surface. We used Perdew-Burke-Ernzerhof (PBE) functional, PBE with dispersion correction (PBE-D2), and van der Waals density functionals (vdW-DFs). We found that the adsorption energy of HCOOH by using the PBE functional is smaller than the experimental value, while the PBE-D2 and vdW-DFs give better agreement with experimental results.

CO adsorption on the copper surfaces: van der Waals density functional and TPD studies.

We investigated the adsorption of CO on the flat, stepped, and kinked copper surfaces from density functional theory calculations as well as the temperature programmed desorption and X-ray photoelectron spectroscopy. Several exchange-correlation functionals have been considered to characterize CO adsorption on the copper surfaces. We used the van der Waals density functionals (vdW-DFs), i.

Desorption dynamics of CO from formate decomposition on Cu(111).

We performed ab initio molecular dynamics analysis of formate decomposition to CO and H on a Cu(111) surface using van der Waals density functionals. Our analysis shows that the desorbed CO has approximately twice larger bending vibrational energy than the translational, rotational, and stretching vibrational energies. Since formate synthesis, the reverse reaction of formate decomposition, has been suggested experimentally to occur via the Eley-Rideal mechanism, our results indicate that the formate synthesis can be enhanced if the bending vibrational mode of CO is excited rather than the translational and/or stretching vibrational modes.

Dissociative adsorption of CO2 on flat, stepped, and kinked Cu surfaces.

We studied the dissociative adsorption of CO2 to CO + O on the Cu(111), Cu(221), Cu(211), and Cu(11 5 9) surfaces by using state-of-the-art density functional theory (DFT) within a generalized gradient approximation (GGA) and van der Waals density functional (vdW-DF) calculations. The activation energy for CO2 dissociation on the flat Cu(111) surface is 1.33 eV.