A numerically controlled elastic emission machining (EEM) system has been developed to fabricate ultraprecise optical components, particularly in x-ray optics. Nozzle-type EEM heads, by which a high shear-rate flow of ultrapure water can be generated on the work surface, have newly proposed transport fine powder particles processing surface. Using this type head, obtainable spatial resolution figure correction changed selecting suitable aperture size nozzle according required frequency. As...

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 adsorption of benzene on the Si(100) surface is studied theoretically using self-consistent van der Waals density functional (vdW-DF) method. energies two competing structures, butterfly (BF) and tight-bridge (TB) are calculated with several vdW-DFs at saturation coverage. Our results show that recently proposed high accuracy all prefer TB to BF, in accord more accurate calculations based exact exchange correlation within random phase approximation. Detailed analyses reveal important...

X-ray photoelectron spectroscopy (XPS) measurements and ab-initio calculations of the XPS chemical shift were performed to identify species plasma-treated polytetrafluoroethylene (PTFE) surfaces. The obtained C1s-XPS O1s-XPS spectra confirmed generation oxygen-containing functional groups on PTFE We investigated effect substitution F atoms in a CF2– chain by H C1s core level binding energy PTFE; our showed that is linearly dependent number substituted atoms. This finding enables us infer...

Identifying the origin of carbon deposition in reactions, such as dry reforming methane (DRM) over cobalt (Co) nanocatalysts, is an important yet challenging issue heterogeneous catalysis. In this study, we used density functional theory (DFT) calculations to investigate surface reactions CO2 with C* at flat and step sites face-centered cubic (FCC) Co [(111), (110), (100), (211), (221)], which represent major surfaces nanoparticles. The results were being compared Ni Hereby, identified that...

Self-regenerative materials are keys to the development of stable catalysts used under high temperature condition, e.g., three-way catalyst converters in automobiles. Among others, metal nanoparticles supported on perovskite oxides promising ones. However, little is known about their atomistic details, which crucial for understanding and thermally catalysts. Herein, we present a machine-learning-enhanced density functional theory study PdxOy Sr3Ti2O7(001) surface demonstrate that oxidized Pd...

We perform machine learning molecular dynamics simulations to gain an atomic-level understanding of the dependence graphitization and thermal degradation behavior diamond (111) (100) surface facets. The interatomic potential is constructed using graph neural network model, trained energies forces from spin-polarized van der Walls-corrected density functional theory calculations. Our results show that C(111) more susceptible degradation, which occurs 2850 K through synchronized bilayer...

We investigated the impact of interaction between gas-phase water molecules and thermally oxidized GeO2 on Ge performance metal–oxide–semiconductor (MOS) structures. A vacuum-integrated setup was developed to form MOS diodes with a GeO2/Ge structure that had been exposed controlled humidity conditions subsequently measure their electrical characteristics in situ. The capacitance–voltage (C–V) curves exhibited significant negative shift, indicating generation positive charges at interface...

Chemical etching of SiC was found to proceed in pure water with the assistance a Pt catalyst. A 4H-SiC (0001) wafer placed and slid on polishing pad water, which thin film deposited give catalytic nature. Etching surface observed remove protrusions preferentially by interacting more frequently, thus flattening surface. In case an on-axis wafer, crystallographically ordered obtained straight step-and-terrace structure, height corresponds that atomic bilayer Si C. The rate depended upon...

Mg/O2 cells employing a MgCl2/AlCl3/DME (MACC/DME) electrolyte are cycled and compared to with modified Grignard electrolytes, showing that performance of magnesium/oxygen batteries depends strongly on composition. Discharge capacity is far greater for MACC/DME-based cells, while rechargeability in these systems severely limited. The Mg/O2-MACC/DME discharge product comprises mixture Mg(ClO4)2 MgCl2, the latter likely formed from slow decomposition former. presence Cl compounds suggests...

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....

The interactions of CO2 with terrace, step, and defect or kink sites on Pt surfaces were investigated using temperature-programmed desorption, X-ray photoelectron spectroscopy, density functional theory calculations. Desorption peaks Pt(997) observed at ∼79, 88–89, ∼92 , ∼103 K respectively assigned to desorption from multilayer (amorphous CO2), sites. sites, step terrace saturated in that order before adsorption occurred. energies the estimated be around −0.23, −0.28, −0.34 eV,...

A highly precise adaptive optical system that can be used in the hard X-ray region was developed. To achieve control of wavefront shape, we discussed an with a bendable mirror deformation accuracy better than 0.4 nm RMS. Using system, demonstrated controllability 15 nanobeam. The intensity profile wavefront-modified beam good agreement wave-optically calculated profile.

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...

It has been observed that the properties of room temperature ionic liquids near solid substrates are different from those bulk liquids, and these play an important role in development catalysts, lubricants, electrochemical devices. In this paper, we report microscopic studies liquid/solid interfaces performed using molecular dynamics simulations. The structural dynamic 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMIM-TFSI) on mica graphite were thoroughly investigated to...

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...

Abstract Formic acid (HCOOH) can be catalytically decomposed into H 2 and CO is a promising hydrogen storage material. As production catalysts, Cu surfaces allow selective HCOOH decarboxylation; however, the on‐surface decomposition reaction pathway remains controversial. In this study, temperature dependence of HCOOH/Cu(111) adsorption structures elucidated by scanning tunneling microscopy non‐contact atomic force microscopy, establishing adsorbate chemical species using density functional...

This work elucidates the surface facet dependence on oxygen adsorption and oxidized morphology of diamond (111) (100) surfaces to give insights that will improve polishing, etching, fabrication devices. We used spin-polarized density functional theory systematically simulate O CO CO2 desorption reactions from pristine etched surfaces. The results show is caused by two factors: (1) difference in reactivity O2 (2) carbonyl orientation O-terminated activation energies C(111)-(2 × 1) are weaker...

We have studied the adsorption of small nitric oxide (NO) clusters [(NO)n (n = 1–3)] on Cu(111), by means van der Waals density functional. found that a single NO molecule preferably adsorbs in an upright N-down configuration at fcc-hollow site, whereas all constituent molecules dimer and trimer adsorb sites, inclined geometries. Among three clusters, is most stable regardless lateral periodicities, good agreement with scanning tunneling microscopy experiment. interaction dominates...

The adsorption of CO on ${\mathrm{Pt}}_{4}$ clusters supported graphene with lattice vacancies is studied theoretically using the first-principles calculation. Our results show that electronic structure graphene-supported significantly modified by interaction carbon dangling bonds. As a result energy at Pt site decreases almost linearly lowering $d$-band center, in analogy linear law previously reported for various surfaces. An exceptional behavior found tetravacancy, where noticeably weaker...