We studied the dissociative adsorption of CO2 to CO + O on 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) van der Waals (vdW-DF) calculations. The activation energy for dissociation flat Cu(111) surface is 1.33 eV. energies stepped kinked are 1.06 eV, 0.67 1.02 eV surfaces, respectively. Even though 0.66 lower Cu(211) than surface, we conclude that does not dissociate "ideal" flat,...

We investigated the adsorption of CO2 on flat, stepped, and kinked copper surfaces from density functional theory calculations as well temperature programmed desorption X-ray photoelectron spectroscopy. Several exchange-correlation functionals have been considered to characterize surfaces. used van der Waals (vdW-DFs), i.e., original vdW-DF (vdW-DF1), optB86b-vdW, rev-vdW-DF2, Perdew-Burke-Ernzerhof (PBE) with dispersion correction (PBE-D2). found that vdW-DF1 rev-vdW-DF2 slightly...

The dangers of ammonia gas (NH3) to human health must be considered. Exposure NH3 can have several adverse effects, including harm the skin; irritation eyes, nose, and throat; damage respiratory system. New materials are being developed for use in sensors mitigate hazards associated with exposure. This study investigated X12Y12 nanocages (X = B, In; Y N, Sb), B12Sb12, In12N12, In12Sb12, specifically their potential as first time, alongside B12N12. Utilizing density functional theory (DFT) at...

We performed density functional theory calculations with van der Waals corrections to elucidate diamond oxidation mechanism on the atomic-level which could lead insights that will advance improvement of nascent nanofabrication technologies. developed a comprehensive oxidative etching (100) surface, from adsorption gas phase O2, including details metastable states, intersystem crossing, and induced surface dereconstruction, desorption CO CO2, complete top layer its subsequent stabilization....

We performed ab initio molecular dynamics analysis of formate decomposition to CO2 and H on a Cu(111) surface using van der Waals density functionals. Our shows that the desorbed has approximately twice larger bending vibrational energy than translational, rotational, stretching energies. Since synthesis, reverse reaction decomposition, been suggested experimentally occur via Eley-Rideal mechanism, our results indicate synthesis can be enhanced if mode is excited rather translational and/or...

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

We have studied the dissociation process of nitric oxide (NO) on Cu(110) and influence hydrogen bond with water by means density functional theory calculations. found that an upright NO adsorbed at a short-bridge site side-on hollow connecting two sites are most stable molecularly states, latter is precursor for process. Various pathways under influences bonds been investigated. efficiently reduce activation energy introductions dimer to O dimers both sides NO, respectively. More...

The structural and electronic properties of naphthalene adsorbed on graphene are studied from first principles using the van der Waals density functional method. It is shown that molecules stabilized by forming a superstructure with periodicity $(2\sqrt{3}\ifmmode\times\else\texttimes\fi{}2\sqrt{3})$ tilted molecular adsorption geometry graphene, in good agreement scanning tunneling microscopy (STM) experiments highly oriented pyrolytic graphite. Our results predict image potential states...

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 deficiency. The effect this deficiency on electronic properties still obscure. Here, we performed a charged point defect calculation h-FeS. We found that most favorable can be tuned with proper synthesis environment. single vacancy could induce midgap state 0.05 eV energy gap, which explains low experimental band gap value....

By using first-principles electronic structure calculations, we study hydrogen monomers and dimers in graphene, the armchair edge \((5,5)\) carbon nanotube (CNT), zigzag \((10,0)\) CNT. We find that above three nanomaterials have a magnetic moment of 1 μB. In case CNTs, atoms are located on outer side CNTs. most stable structures materials, two bonded to host which nearest-neighbors. opposite sides, whereas CNT CNT, both side. The geometries found be nonmagnetic. However, when...

Understanding the nature of active sites is a non-trivial task, especially when catalyst sensitively affected by chemical reactions and environmental conditions. The challenge lies on capturing explicitly dynamics evolution during reactions. Despite complexity reconstruction, we can untangle them into several elementary processes, which surface diffusion prime importance. By applying density functional theory-kinetic Monte Carlo (DFT-KMC) simulation employed with cluster expansion (CE),...

We investigate the polymeric adsorption of formic acid (HCOOH) on Cu(111) surface by means density functional theory. present structural models for form HCOOH and characterize their stability, electronic, vibrational properties. Based energetics dynamics, as well simulated scanning tunneling microscopy atomic force images, we propose that $\ensuremath{\alpha}$ polymorph is likely to be formed can explain experimental findings. also study initial step catalytic dehydrogenation find O-H bond...

Computer science and technology development in recent years has experienced great developments. This time, some types of digitise almost everything related to human life, including facial recognition. In years, various methods for recognising faces have developed. One them is using the Histogram Oriented Gradients (HOG). On this occasion, an image processing system will be designed recognise Histograms (HOG) machine learning such as Convolutional Neural Networks (CNN) Support Vector Machines...

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

These days, during the issues of climate change, there has been a shift in energy industry from using fossil fuels to more environmentally friendly such as biomass fuels. Biomass fuel is considered CO2 neutral because carbon produced combustion form emissions can be used for new plant growth. However, besides advantages fuel, problem arises when contains high concentration corrosive agents, which released along with hot gas. agents damage boiler components. Coating technology one solutions...

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

Penelitian ini bertujuan untuk menentukan faktor risiko sindrom Down dari data kasus-kontrol menggunakan mesin pembelajaran. Metode yang digunakan meliputi random forest, k-nearest neighbors, support vector machine (SVM), naive bayes, k-means, dan artificial neural network (ANN). Data memiliki tiga subjek kelompok, (41 baris), tuna grahita tanpa kebutuhan khusus (27 baris) dengan total 37 variabel. Tingkat akurasi setiap metode ditentukan oleh jenis jumlah variabel digunakan. Kelompok...

Abstract Supercapacitor gains so much interest in recent years due to its capabilities provide high power densities with energy density possibilities. Several transition metal sulfides (TMS) give the best capacitance results nowadays, Copper Sulfides (CuS) promising candidates on supercapacitor electrodes materials. approaches have been made increase TMS-based performance, such as doping, surface functionalization, and nanostructuring. Even though several dopants already reported, other not...

The substitutional impurities in zigzag edge (10,0) carbon nanotubes have been studied by using first principles calculations. Silicon (Si), gallium (Ga), and arsenic (As) atom chosen as semiconductor based-atom for replacing atoms CNT's surface. silicon changes the energy gap of pristine CNT, it is 0.19 eV more narrow than that CNT. Geometrically, creates sp3 bond with three adjacent atoms, where tetrahedral form its consisted free unoccupied state. does not induce magnetism to Due (Ga)...

We carry out first-principles calculations of the atomic hydrogen adsorption on capped armchair edge (5,5) carbon nanotubes (CNT) by using density functional theory based spin polarized generalized gradient approximation. Based calculated binding energies atoms, we find that cap region is easily hydrogenated compared with tube region. Odd numbers atoms induce magnetic moment 1 µ B , whereas even lead to nonmagnetism. energetics, expect hydrogenation process as follows: when are adsorbed one...