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The effects of tensile and compressive deformation on the structural stability, electronic structure and optical properties of the Zn atom-adsorbed borophene system, which are exhibited by reflectivity, absorption coefficient, bandgap and adsorption energy, were studied using the first-principles calculations based on density functional theory (DFT). The borophene planes were found to be distorted following Zn atom adsorption. The adsorption energy calculations show that the stability decreases both under tensile and compressive strains. When tensile and compressive loading increase to 5%, respectively, the system loses the stability and the ability of adsorbing Zn atoms on borophene. The band structure and density of states analysis show that the band structure of borophene is changed by the Zn atom adsorption, with a band overlap near the Fermi level and more impurity energy levels in the conduction band. The hybridization is formed between Zn atom and borophene in the range of –12 eV to 6 eV, with the s and p orbitals both contributing to the conduction and valence bands, but p orbitals make a larger contribution to the total density of states than s orbitals. Studies of optical properties have shown that tensile and compressive strains both increase the dielectric constant of the adsorbed system, with compressive strains causing a redshift in the major peaks of the real and imaginary parts of the spectrum. The tensile strain has little effect on the absorption coefficient and reflectance of the borophene. As the compressive strain increases, the peak absorption coefficient of the adsorbed system is shifted to the blue and the peak reflectance is redshifted. [ABSTRACT FROM AUTHOR]

With the development of industrialization, the use of mercury in industry has become more and more widespread, causing serious impacts on the environment. It is therefore urgent to find new effective ways to combat mercury pollution. In this paper, The effect of C, O, P, Ni and Au doping on the adsorption of Hg atoms by WS 2 has been investigated based on the first nature principle of density functional theory. The electronic structures and optical properties of the adsorbed systems were calculated after atomic doping. The results show that the absolute value of the adsorption energy of the intrinsic adsorption system is small and does not favour the adsorption of Hg on WS 2. However, after C, P, Ni and Au doping, the adsorption energy of the system is significantly increased and a strong charge transfer between WS 2 and Hg atoms occurs, as well as a significant change in the band gap of the structure. This suggests that atomic doping favors the adsorption of Hg by WS 2. The effect of O doping on the adsorption system is not significant. In addition, a study of the optical properties revealed that the static dielectric constants of the system appeared to increase to varying degrees after the doping of the atoms. The doping of P, Ni and Au atoms increases the light absorption coefficient and contributes to the photocatalytic efficiency of the structures. The doped atoms cause a red shift in the reflectivity peak of the adsorbed system. In summary, the doping of C, P, Ni and Au enhances the adsorption of Hg atoms on WS 2. O doping has less effect on the adsorption of Hg on WS 2. • In this paper, the effect of C, O, P, Ni and Au doping on the adsorption of Hg atoms by WS2 was investigated. • The results show that atomic doping favors the adsorption of Hg by WS2. • Atomic doping alters the electronic properties of the structure. • Atomic doping alters the optical properties of the structure. [ABSTRACT FROM AUTHOR]

First-principles research has been used to carefully examine the structural stability of the architecture, electronic structure, and optical characteristics of monolayer WS2-doped Mo atoms during shear deformation. Calculations show that the required formation energy gradually increases when shear deformation is increased from 2% to 8%, the bandgap of the system decreases from 1.732eV to 0.922eV, and the static dielectric function increases from 2.59 to 2.74. The absorption peaks are maximum for all doped systems between 11.5eV and 12.5eV. The peak absorption of the deformed system is redshifted compared to the original doped system. With increasing shear deformation, the peak energy loss of the system shows a decrease followed by an increase. [ABSTRACT FROM AUTHOR]

In the present paper, the effect of different bent angles on structural stability, electronic structure, and optical properties of Na absorbed borophene system is investigated using the density functional theory. The structure of the borophene was almost unchanged and the planar structure was not disrupted after the adsorption of a Na atom. Directly above the bottom B–B bonds is considered as the optimal adsorption position of single. The stability of the Na adsorbed borophene system can be decreased under the condition of different bent angles. The adsorption of Na atoms changes the energy band structure of the intrinsic borophene according to the calculation results of energy band structure and density of states, which resulting the conduction band contains more impurities. The 2p orbital of Na and the 3p orbital of B hybridize between −4 eV and 6 eV. Bending deformation gives rise to the electron transfer between Na atoms and B atoms. In terms of optical properties, the bending deformation improves the absorption of infrared light and the catalytic activity of light in the adsorbed system. • The structure of the borophene was almost unchanged and the planar structure was not disrupted after the adsorption of a Na atom. • The stability of the Na adsorbed borophene system can be decreased under the condition of different bent angles. • The adsorption of Na atoms changes the energy band structure of the intrinsic borophene so that its conduction band contains more impurities. • The bending deformation improves the absorption of infrared light and the catalytic activity of light in the adsorbed system. [ABSTRACT FROM AUTHOR]

Abstract: Fe-doped hydrogenated amorphous carbon (a-C:H:Fe) films were deposited from an isobutene/ferrocene/H2 gas mixture by plasma enhanced chemical metal organic vapor deposition. Raman spectra were used to characterize the bonding structure of the a-C:H:Fe films and hydrogenated amorphous carbon (a-C:H) films. Optical properties were investigated by the UV–vis spectroscopy and the photoluminescence spectra. The number of six-numbered rings of the a-C:H films increases and sp 2 clustering of the films decreases after Fe-doping. The Tauc optical gap of the a-C:H:Fe films becomes narrower by 0.15–0.23eV relative to the value of the a-C:H films. The narrowing of the optical gap after doping is attributed primarily to the extended state around the Fe deep level in the band gap and the narrowing of the π and π* band edge states because of the increase of the number of six-numbered rings in the a-C:H films. Fe deep level defects of the a-C:H:Fe films contribute chiefly to non-radiative recombination. [Copyright &y& Elsevier]