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Rapid recombination of the photo-generated charge carriers leads to the poor photocatalytic nitrogen fixation property of pristine graphite-like carbon nitride (g-C 3 N 4). To enhance the photocatalytic performance of g-C 3 N 4 , nickel sulfide (NiS) nanoparticles were anchored onto the surface of g-C 3 N 4 by using the in-situ decomposition-thermal polymerization method in this work. The incorporation of NiS cocatalyst expanded the absorption range, enhanced the efficiency of separating photo-generated charge carriers, reduced the band gap from 2.78 eV to 2.47 eV, increased the specific surface area 7.1 m2·g−1 to 19.5 m2·g−1, and enlarged the photo-current density, which can inhibit the recombination of photo-generated charge carriers. Furthermore, the emergence of the nitrogen vacancy occurred during the in-situ synthetic process as a result of the thermal decomposition of thioacetamide hydrolysate, thereby leading to an enhancement in the photocatalytic nitrogen fixation efficiency. The results of the nitrogen fixation experiment demonstrated that 13 % NiS/g-C 3 N 4 exhibited the highest activity, with a photocatalytic nitrogen fixation rate of 8.15 mg/L. This rate is 7.6 times greater than that of pure g-C 3 N 4 , which can be attributed to several factors, including a higher separation rate of photogenerated electrons, a larger specific surface area, a wider range of responsiveness to visible light, and the presence of the nitrogen vacancy. [Display omitted] • NiS modified g-C 3 N 4 is prepared by an in-situ decomposition-thermal polymerization. • NiS/CN shows nitrogen vacancy, wide absorption range and efficient charge transfer. • NiS/CN exhibits enhanced photocatalytic nitrogen fixation performance. [ABSTRACT FROM AUTHOR]

Ternary Si–C–N films were produced in a radiofrequency plasma enhanced chemical vapor deposition reactor applying the precursor gases silane, methane, and nitrogen or ammonia. The properties of the films to function as external moisture barrier layers were investigated with emphasis on the correlation of deposition parameters and moisture permeation rate. The moisture penetration through the films has been investigated in water vapor permeation experiments and capacitance measurements from humidity sensors in plastic packages. The moisture resistance is mainly influenced by the stress in the films with best results for those samples exhibiting no or low compressive stress. [Copyright &y& Elsevier]

• Ag/B-doped g-C 3 N 4 was prepared by an in-situ decomposition-thermal polymerization. • Ag/B-doped g-C 3 N 4 showed reduced band gap and efficient charge separation. • Ag/B-doped g-C 3 N 4 exhibited enhanced photocatalytic nitrogen fixation performance. Photocatalytic nitrogen fixation is considered as a promising strategy for ammonia production. In this study, non-metallic boron and noble metal silver modified graphitic carbon nitride were prepared by a direct in-situ decomposition-thermal polymerization method with dicyandiamide, boric acid and silver nitrate as the precursors. It was shown that Ag/B-doped g-C 3 N 4 composites with optimal mass ratio exhibited improved photocatalytic ammonia production under simulated sunlight illumination by a factor of 5.5 and 1.5 times compared with the pristine g-C 3 N 4 and B-doped g-C 3 N 4 , respectively. The superior photocatalytic property was attributed to the decreased band gap and formation of mesopores after boron doping, which enlarged the specific surface area and created abundant reactive sites on the g-C 3 N 4 nanosheets. In addition, the loaded silver nanoparticles greatly inhibited the recombination of photogenerated charge carriers through heterojunction interface. This work provided new deep insights into the reasonable structure of g-C 3 N 4 composite system for photocatalytic nitrogen fixation reactions. [ABSTRACT FROM AUTHOR]