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-C₃N₄ 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-C₃N₄ and B-doped g-C₃N₄, 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-C₃N₄ 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-C₃N₄ composite system for photocatalytic nitrogen fixation reactions.

光催化固氮被认为是氨生产的有前途的策略。本研究以双氰胺，硼酸和硝酸银为前驱体，通过直接原位分解-热聚合法制备了非金属硼和贵金属银改性石墨碳氮化物。结果表明，与原始gC ₃ N ₄和B掺杂的gC ₃ N相比，具有最佳质量比的Ag / B掺杂的gC ₃ N ₄复合材料在模拟阳光照射下的光催化氨生成提高了5.5倍和1.5倍。₄， 分别。优异的光催化性能归因于硼掺杂后带隙的减小和中孔的形成，这扩大了比表面积并在gC ₃ N ₄纳米片上创建了丰富的反应位点。另外，负载的银纳米颗粒极大地抑制了光生电荷载流子通过异质结界面的重组。这项工作为光催化固氮反应的gC ₃ N ₄复合体系的合理结构提供了新的深刻见解。