In situ generation of oxyanions-decorated cobalt(nickel)oxyhydroxide catalyst with high corrosion resistance for stable and efficient seawater oxidation

The development of efficient and robust anode materials for stable alkaline seawater electrolysis is severely limited by chlorine evolution reaction and chloride corrosion.Here,the sulfur-doped cobalt-nickel bimetallic phosphides(CoNiPS)are specifically designed as a pre-catalyst for navigating a surface reconstruction to fabricate the anions(PO^(3-)_(4) and SO^(2-)_(4))-decorated Co(Ni)OOH catalyst(R-CoNiPS)with exceptional durability and high activity for stable alkaline seawater oxidation(ASO).Various experiment techniques together with theoretical simulations both demonstrate that the in situ-generated PO^(3-)_(4) and SO^(2-)_(4) anions on catalyst surface can improve the oxygen evolution reaction(OER)activity,regulating and stabilizing the catalytic active species Co(Ni)OOH,as well as make a critical role in inhibiting the adsorp-tion of chloride ions and extending the service life of electrode.Therefore,this R-CoNiPS electrode exhi-bits superb OER activity toward AsO and stands out among the non-precious ASO electrocatalysts reported recently,requiring low overpotentials of 420 and 440 mV to attain large current densities of 500 and 1000 mA cm^(-2) in an alkaline natural seawater electrolyte,respectively.Particularly,the catalyst displays a negligible chloride corrosion at room temperature during ASO operation(>200 h)at 500 mA cm^(-2).This work opens up a new viewpoint for designing high-activity and durable electrocata-lystsforseawaterelectrolysis.

A proposal for detecting weak electromagnetic waves around 2.6μm wavelength with Sr optical clock

Infrared signal detection is widely used in many fields.Due to the detection principle,however,the accuracy and range of detection are limited.Thanks to the ultra stability of the^(87)Sr optical lattice clock,external infrared electromagnetic wave disturbances can be responded to.Utilizing the ac Stark shift of the clock transition,we propose a new method to detect infrared signals.According to our calculations,the theoretical detection accuracy in the vicinity of its resonance band of 2.6μm can reach the order of 10-14W,while the minimum detectable signal of common detectors is on the order of 10^(-10)W.

Two-dimensional particle-in-cell modeling of blow-off impulse by X-ray irradiation

Space objects such as spacecraft or missiles may be exposed to intense X-rays in outer space,leading to severe damage.The reinforcement of these objects to reduce the damage caused by X-ray irradiation is a significant concern.The blow-off impulse(BOI)is a crucial physical quantity for investigating material damage induced by X-ray irradiation.However,the accurate calculation of BOI is challenging,particularly for large deformations of materials with complex configurations.In this study,we develop a novel two-dimensional particle-in-cell code,Xablation2D,to calculate BOIs under far-field X-ray irradiation.This significantly reduces the dependence of the numerical simulation on the grid shape.The reliability of this code is verified by simulation results from open-source codes,and the calculated BOIs are consistent with the experimental and analytical results.

Modulation on electrostatic potential to build a firm bridge at NiO_(x)/perovskite interface for efficient and stable perovskite solar cells

The NiO_(x)/perovskite interface in NiO_(x)-based inverted perovskite solar cells(PSCs)is one of the main issues that restrict device performance and long-term stability,as the unwanted interfacial defects and undesirable redox reactions cause severe interfacial non-radiative recombination and open-circuit voltage(Voc)loss.Herein,a series of self-assembled molecules(SAMs)are employed to bind,bridge,and stabilize the NiO_(x)/perovskite interface by regulating the electrostatic potential.Based on systematically theoretical and experimental studies,4-pyrazolecarboxylic acid(4-PCA)is proven as an efficient molecule to simultaneously passivate the NiO_(x)and perovskite surface traps,release the interfacial tensile stress as well as quench the detrimental interface redox reactions,thus effectively suppressing the interfacial non-radiative recombination and enhancing the quality of perovskite crystals.Consequently,the PSCs with 4-PCA treatment exhibited an eminently increased Voc,leading to a significant increase in power conversion efficiency from 21.28%to 23.77%.Furthermore,the unencapsulated devices maintain 92.6%and 81.3%of their initial PCEs after storing in air with a relative humidity of 20%–30%for 1000 h and heating at 65℃for 500 h in a N_(2)-filled glovebox,respectively.

Proton Transport in Hydrogen-bonded Systems in Anharmonic Interaction Approximation : an Analytical Approach

We study the collective proton motion in hydrogen-bonded systems in anharmonic interaction approximation,and obtain analytical solutions of kinkantikink solitons.The asymmetric feature of kink-antikink solitons can be clearly seen from the solutions.Some basic physical quantities of the kink and antikink solitons are calculated in anharmonic interaction approximation.

A K-CELL injection system for SH-PermEBIT

In this paper,we report a newly developed Knudsen Cell injection system for SH-PermEBIT.This technique can overcome disadvantages of introducing organometallic gases and wired probes into EBIT and provide steady continuous injection.A specially designed vacuum line is used to ensure that the Knudsen Cell satisfies the vacuum level of SH-permEBIT.Using this system we successfully injected ytterbium into the SH-permEBIT and recorded a spectrum in the visible wavelength region.

Resonance Excitation Rate Coefficient of Ni-Like Tantalum

The ab initio calculations of electron-impact resonant excitation rate coefficients from the ground level to 54 fine-structure levels of 3d94l （1 = s, p, d, f） configurations of Ni-like tantalum ion are performed by using a fully relativistic distorted-wave approximation. The configuration-interaction effects are taken into account. The decays to autoionizing levels possibly followed by autoionization cascades are also included in the calculation. The contributions from doubly-excited intermediate states of Cu-like 31^17n′l′n′l″ （n′ = 4, 5; n″ = 5 - 15） are calculated explicitly, and the contributions from high Rydberg states （n″〉 15） are taken into account by using n-3 scaling law. The present results should be more accurate than the existent calculations.

Calculation of photon angular distribution and polarization for radiative recombination for high-charged hydrogen-like ions

In this paper a systematic study is carried out on the angular distribution and polarization of photons emitted following radiative recombination of H-like ions by a non-relativistic dipole approximation. In order to incorporate the screening effect due to inner-shell electrons, a distorted wave approazh is used. The dependences of the calculated angular distribution and polarization on the reduced energy and nuclear charge are fitted by the corresponding empirical formulas respectively.

Experimental Study of Single and Double Electron Detachment Cross Sections for Cl^- in Collision with He

Single-electron detachment （SED） and double-electron detachment （DED） for chlorine negative ions in collision with helium are investigated in the energy region of 5-30 keV （SED） and 5-19 ke V （DED） by growth rate method, respectively. Experimental data from this work are compared with the previous reported data, and a general discussion is given.

THE EFFECT OF SODIUM ADLAYERS ON THE ADSORPTION OF OXYGEN ON Ag(100)

The application of HREELS to the study of the Ag(100)/Na+O_(2) system reveals the presence of molecularly adsorbed oxygen species at room temperature.This may help explain why alkali metals can enhance the selectivity of an Ag catalyst towards the formation of C_(2)H_(4)O.

THE MECHANISM OF SURFACE SEGREGATION BY THE METHOD OF MECHANICAL POLISHING

Mechanical polishing and subsequent thermal oxidation are the indispensable condition for rapid formation of a continuous and highly Cr-enriched layer on the surface of a Ni-Cr alldy.Direct observations of the Cr distribution on the surface by Auger map show a possible process for Cr segregation.The huge amount of grain boundaries created by mechanical polishing promote the upward diffusion of Cr.Selective oxidation and Cr-holding effect also speed up the formation of Cr_(2)O_(3).

THEORETICAL STUDIES OF C1 ON Ag(100) SURFACE BY SW-X_(α)-SCF METHOD

For solving the long existing controversy about the chemisorption geometry of Cl/Ag(100),we show,by a SW-X_(α)-SCF cluster calculation,that the SOM(simple overlayer model)is more plausible.This conclusion agrees quite well with the more recent high resolution results obtained by angle-resolved photoemission.

THE ELIMINATION OF In ISLANDS ON InP SURFACES AND ITS MECHANISM

The surface indium islands originated by argon ion bombardment can be removed by evaporating phosphorous on InP surface followed by annealing.A possible mechanism of elimination of In islands is proposed based on the experimental ELS and XPS data.

THERMAL DESORPTION STUDY OF DEUTERIUM ON Si (100) SURFACE

The thermal desorption spectra study of deuterium on Si(100)surface shows that two adsorption states the monodeuteride phase and the dideuteride phase can be formed.The activation energies of desorption for these two phases have been measured and a comparison with the hydrogen adsorption on Si(100)surface has been made.

CHARGE FLUCTUATION AND HIGH-T_(C) SUPERCONDUCTIVITY

Cluster model is used to simulate several optical vibration modes of oxygen in the.layered perovskite La-Ba-Cu-o.the breathing mode of 0xygen induces a charge It is found that only fluctuation between Cu-sites.The charge fluctuatson Ls reasonably large and may have 1mpor-tant.implications in the high-T_(c) superconduc ctivity.

THE VARIATION OF IN ISLANDS ON InP SURFACE VERSUS ION SPUTTERING ANGLE OBSERVED BY THE ELECTRON ENERGY LOSS SPECTROSCOPY

The idea of using grazing angle ion sputtering to minimize the-formation of In islands on InP(111)surface has been presented and its correctness has been proved by the measurement of electron energy loss spectroscopy.

THE FRACTIONAL FERMION NUMBER AND FRACTIONAL CHARGE INDUCED BY MAGNETIC MONOPOLE

Based on the Levinson theorem and using the method of Green's function,we derive the general expressions of fractional charge and fractional fermion number induced by the background field of t'Hooft-Polyakov magnetic monopole.

ION-BOMBARDMENT-ENHANCEC DIFFUSION PHENOMENON IN Pb-Sn ALLOY

The surface phenomena of Pb-Sn alloy under the Ar^(+) ion bombardment have been investigated by using a PHI-590 scanning Auger microprobe at room temperature.Theoretical analysis of experimental data showed that ion-bombardment-enhanced diffusion had occurred with a diffusion coefficient up to 10^(-15)cm^(2)/sec.A possible explanation is given.

Dielectronic recombination of Co-like tantalum

Ab initio calculation of the total dielectronic recombination （DR） rate coefficient from the ground state of Co-like tantalum is performed using the relativistic distorted-wave approximation with configuration interaction. The contributions to the total DR rate coefficients are explicitly calculated from the complexes of Ni-like tantalum：3s^23p^63d3/2^33d5/2^6n′l′,3s^23p^53d^10n′l′,3s3p^63d^10n′l′,3s^23p^63d^84ln′l′,3s^23p^53d^94ln′l′ and 3s3p^63d^94ln′l′ with n′≤25, and 3s^23p^63d^85ln′l′ with n′≤9.The l′and n′ dependences of partial DR rate coefficients are investigated. The contributions from higher n^complexes are evaluated by a level-by-level extrapolation method. The total DR rate coefficients mainly come from the complex series 3s^23p^63d^84ln′l′,3s^23p^53d^94ln′l′and are fitted to an empirical formula with high accuracy. Comparison of the present results with those of other works shows that the previously published data underestimate significantly the DR rates of Co-like tantalum.

Energy Spectrum Symmetry of Heisenberg Model in Fock Space

We extend the BCS paring model with equally spaced energy levels to a general one-dimensional spin-1/2 Heisenberg model The two well-known symmetries of the Heisenberg model, i.e. permutational and spin-inversion symmetries, no longer exist. However, when jointing these two operations together, we find a new symmetry of energy spectrum between its subspace n and subspace L - n of the Fock space. A rigorous proof is presented.