Research Development on Graphitic Carbon Nitride Nanosheets

露 陈
2015 Advances in Material Chemistry  
摘要:采用第一性原理密度泛函理论结合周期性平板模型模拟研究了 Pt4团簇吸附单层石墨相氮化碳(g-C3N4) 的几何结构和电子性质,以及氧气在其表面上的吸附行为。同时,对比分析了氧气在纯净的石墨相氮化碳和 Pt4团簇上的吸附行为。计算结果表明,Pt4团簇吸附在 3-s-三嗪环石墨相氮化碳表面,并与四个边缘氮原子 Abstract: The structural and electronic properties of Pt4 nanoparticles adsorbed on monolayer graphitic carbon nitride (Pt4/g-C3N4), as well as the adsorption behavior of oxygen molecules on the Pt4/g-C3N4 surface have been investigated through first-principles density-functional theory (DFT) calculations with the generalized gradient
more » ... imation (GGA). The interaction of the oxygen molecules with the bare g-C3N4 and the Pt4 clusters was also calculated for comparison. Our calculations show that Pt nanoparticles prefer to bond with four edge N atoms on heptazine phase g-C3N4 (HGCN) surfaces, forming two hexagonal rings. For s-triazine phase g-C3N4 (TGCN) surfaces, Pt nanoparticles prefer to sit atop the single vacancy site, forming three bonds with the nearest nitrogen atoms. Stronger hybridization of the Pt nanoparticles with the sp 2 dangling bonds of neighboring nitrogen 1183 Acta Phys. -Chim. Sin. 2016 Vol.32 atoms leads to the Pt4 clusters strongly binding on both types of g-C3N4 surface. In addition, the results from Mulliken charge population analyses suggest that there are electrons flowing from the Pt clusters to g-C3N4. According to the comparative analyses of the O2 adsorbed on the Pt4/HGCN, Pt4/TGCN, and pure g-C3N4 systems, the presence of metal clusters promotes greater electron transfer to oxygen molecules and elongates the O-O bond. Meanwhile, its greater adsorbate-substrate distortion and large adsorption energy render the Pt4/HGCN system slightly superior to the Pt4/TGCN system in catalytic performance. The results validate that being supported on g-C3N4 may be a good way to modify the electronic structure of materials and their surface properties improve their catalytic performance.
doi:10.12677/amc.2015.32003 fatcat:xzls4c5lxva57aobdihlsl7nwu