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In order to enhance the corrosion protection of K2SiO3 coatings， SiO2 aerogel (SA) was used as a carrier loaded with 70 mg/mL benzotriazole (BTA) corrosion inhibitor (SA＠BTA-70).The SA＠BTA-70 dispersion and BTA slow-release properties in K2SiO3 solution were researched，and their influence on the corrosion resistance of K2SiO3 coatings were also investigated.Moreover，the surface change of SiO2 aerogel before and after heat treatment at 600 ℃was investigated by Fourier transform infrared spectrometer， specific surface area adsorption tester， etc.to improve its dispersibility in aqueous K2SiO3.Through TGA and UV-vis monitoring，it was found that the effective load of BTA in SiO2 aerogel was 17.6%(mass fraction)， and it had good slow-release performance under weak acidic / alkaline condition.Electrochemical impedance spectroscopy (EIS) results showed the low-frequency impedance of the K2SiO3 coating containing SA＠BTA-70 was around 5.0 ×103 Ω·cm2.The neutral salt spray resistance test showed that no obvious rust spots appeared after salt spray resistance test for 30 d， demonstrating the coating possessed excellent corrosion protection ability.From the above results， it could be obtained that SiO2 aerogel effectively loaded BTA corrosion inhibitor， and had good slow release in K2SiO3 solution， which effectively improved the corrosion resistance of K2SiO3 coatings.

PDMS-based aerogel layers were synthesized as insulation layers by adopting mullite fiber (MF), hollow glass microspheres (HGM) and silica aerogel (SA) as the main fillers, and their loading amounts and content ratios were checked to investigate their effects on the thermal insulation properties in PDMS composites by thermal conductivity, thermal stability, and thermal insulation. The loading amount of nanofillers can significantly influence the insulation-layer performance, and the best performance with the lowest thermal conductivity of 0.0568 W/(m·K) was obtained by 10 wt% loading in PDMS with MF:SA:HGM = 2:2:1, which can achieve a temperature difference (∆T) of 67 °C on a 200 °C hotplate. Moreover, the variation of the filler content ratios can also affect the thermal insulation behavior when the loading amount is fixed at 10 wt%, and the best thermal barrier performance can be found for the sample with more SA as the filler (MF:SA:HGM = 1:3:1). The formed sample had the best thermal stability and thermal insulation property, which can stand a 9 min flame test without burning by butane spray gun, and the backside of the sample showed ∆T > 500 °C for the whole test. [ABSTRACT FROM AUTHOR]

Layered TiO2 sheets with high Cr(VI) photoreduction ability were prepared by template free solvothermal method using ethylene glycol (EG) as structure directing agent. EG linking function in the layered TiO2 structure were confirmed by SEM, TEM, FTIR, XPS and so on. Moreover, the obtained large sized TiO2 (20~50 μm in length, about 5~10 μm in width) were assembled by N‐doped TiO2 thin sheets with about 1.2 nm gap in between, resulting in very high surface area (327.5 m2/g) and abundant Ti3+ sites for Cr(VI) adsorption and reduction. This structure can not only have good performance during Cr(VI) photocatalysis reduction application (Cr(VI) removal rate: 0.84 mg*g−1*min−1), but also endow the material with good cycle ability. [ABSTRACT FROM AUTHOR]

A3 coupling reaction can be used to efficiently synthesize propargylamine, which is an important bioactive molecule intermediate, and copper sulfide (CuS) as its catalyst is rarely reported. Herein, CuS with different morphologies including nanoflowers (NFS), nanorods (NR), nanoparticles (NP) were synthesized and applied to the A3 coupling reaction. The results show that CuS NP has the highest catalytic activity (99 % conversion) compared to other CuS, and also has good group compatibility and recyclability. Combining the activity with the CuS surface structure checked by XPS, BET and HRTEM etc. the excellent catalytic performance of CuS NP can be attributed to its higher specific surface area ((SBET=26.9 m2/g, SLangmuir=144.2 m2/g), and higher Cu+/Cu0 (58.9 %), Sn2− (16.7 %). The large specific surface area can provide more active sites, and higher Cu+/Cu0, Sn2− content are conducive to promoting the activation of alkyne terminal C−H, which is an important step in the A3 coupling reaction. [ABSTRACT FROM AUTHOR]

As supported CuO is well-known for low temperature activity, CuO/CeO2 nanosphere catalysts were synthesized and tested for CO oxidation and preferential oxidation of CO (PROX) in excess H2. For the first reaction, ignition was observed at 95 °C, whereas selective PROX occurred in a temperature window from 50 to 100 °C. The catalytic performance was independent of the initial oxidation state of the catalyst (CuO vs. Cu0), suggesting that the same active phase is formed under reaction conditions. Density functional modeling was applied to elucidate the intermediate steps of CO oxidation, as well as those of the comparably less feasible H2 transformation. In the simulations, various Cu and vacancy sites were probed as reactive centers enabling specific pathways. [ABSTRACT FROM AUTHOR]