The effect of n–π* electronic transitions on the N₂ photofixation ability of carbon self-doped honeycomb-like g-C₃N₄ prepared via microwave treatment

Abstract

Light harvesting is an important part of the photocatalysis process.

Multiple ordered porous honeycombed g-C3N4 with carbon ring in-plane splicing for outstanding photocatalytic H2 production

“…In addition, C r –PHCN shows an obvious strong absorption peak at 1216 cm −1 , which should be attributed to the extra C–C bond caused by the splicing carbon rings. 23 X-ray photoelectron spectroscopy (XPS) was conducted to further reveal the surface chemical composition and elemental status of the as-prepared samples, and the C 1s high-resolution spectra are shown in Fig. 2c.…”

“…Of these, the n → π* transition originates from the lone pair electrons on N atoms, which can extend the π-conjugation system and form delocalized big π bonds. 23–25 As has been reported, g-C 3 N 4 with a doped carbon source is an effective electronic modulation strategy without introducing extraneous dopants. 26 Particularly, the graphitic carbon ring (C r ) has a similar aromatic triazine structure and can be in-plane embedded in g-C 3 N 4 , which can significantly narrow the band gap and improve electrical conductivity.…”

Photocatalytic Fixation of Molecular Nitrogen in Systems Based on Graphite-Like Carbon Nitride: a Review

“…Nonmetals. Carbon self-doped honeycomb-like g-C 3 N 4 , synthesized by MWT of supramolecular aggregates formed by the interaction of melamine with cyanuric acid in ethylene glycol, showed high photocatalytic activity in nitrogen photofixation [93]. Ethylene glycol not only acted as a solvent but was also a source of carbon doping.…”

Intrinsic Defects in Polymeric Carbon Nitride for Photocatalysis Applications

“…Traditional artificial nitrogen fixation techniques by Haber-Bosch process is now below the standards of modern chemical industry owing to its high power-consumption, high risk and serious environmental pollutants. [42] Recently, photocatalytic nitrogen fixation into ammonia has been considered as a promising alternative method due to its moderate conditions and environmental-friendly process. [31] Nitrogen vacancies (NVs) is considered as an excellent candidate for photocatalytic N 2 fixation, because nitrogen vacancies can favor the selective chemiadsorption and activation of N 2 due to the similar size and shape of NVs and N atoms in N 2 molecules.…”

“…Traditional artificial nitrogen fixation techniques by Haber‐Bosch process is now below the standards of modern chemical industry owing to its high power‐consumption, high risk and serious environmental pollutants [42] . Recently, photocatalytic nitrogen fixation into ammonia has been considered as a promising alternative method due to its moderate conditions and environmental‐friendly process [31] .…”