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Density functional theory is used to investigate the effects of coverage and solvent on the adsorption of H 2 S on the Cu(100) surface. In this work, the adsorption energies, structural parameters and Mulliken charges of the adsorbed H 2 S are calculated. The results show that when the coverage of H 2 S is high (1 ML), H 2 S molecule cannot adsorb on the Cu(100) surface spontaneously, and the decomposition of H 2 S preferentially occurs at the bridge site. When the coverage decreases to 1/4 ML coverage, H 2 S molecule does not exhibit the decomposition, but bonds to the top Cu atom with the tilted adsorption. Furthermore, when the coverage is 1/9, 1/16 and 1/25 ML, H 2 S adsorption remains stable. In addition, the stability of H 2 S adsorption on the Cu(100) surface improves rapidly when the solvent dielectric constant (ε) increases from 1 to 12.3 corresponding to the vacuum and pyridine, respectively. For the higher ε (≥24.3), the effect of the solvent on the H 2 S adsorption was greatly reduced. In this work, both coverage and solvent are shown to have an important effect on the H 2 S adsorption on the Cu(100) surface, which might be useful to improve the future similar simulations.

In this paper, high-performance silica aerogel (SiO2 aerogel) thermal insulation coatings were obtained and profited from the excellent thermal insulation capability of SiO2 aerogel. The comprehensive properties and thermal insulation mechanism of the coatings were investigated via Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), contact angle, and temperature difference tests. Results showed that there was a contradiction between thermal insulation and mechanical property in this coating after the addition amount and proportion of silica aerogel, hollow glass microsphere, glass fibers, aqueous acrylic emulsion, and dispersing agents were optimized carefully. When the mass ratio of hollow glass to SiO2 aerogel microspheres was 1:1, the overall performance of the coating was the best with thermal conductivity of 0.050 W/(m·K) and adhesive strength of 1024 kPa.

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