Graphene-analogue carbon nitride: novel exfoliation synthesis and its application in photocatalysis and photoelectrochemical selective detection of trace amount of Cu²⁺

Abstract

Graphene-analogue nanostructures defined as a new kind of promising materials with unique electronic, surface and optical properties have received much attention in the fields of catalysis, energy storage, sensing and electronic devices. Due to the distinctive structure characteristics of the graphene-analogue materials, they brought novel and amazing properties. Herein, graphene-analogue carbon nitride (GA-C₃N₄) was synthesized by high-yield, large-scale thermal exfoliation from the graphitic C₃N₄-based intercalation compound. Graphene-analogue carbon nitride exhibited 2D thin-layer structure with 6-9 atomic thickness, a high specific surface area of 30.1 m(2) g(-1), increased photocurrent responses and improved electron transport ability, which could give rise to enhancing the photocatalytic activity and stability. The graphene-analogue carbon nitride had a new features that could make it suitable as a sensor for Cu(2+) determination. So GA-C₃N₄ is a new but promising candidate for heavy metal ions (Cu(2+)) determination in water environment. The photocatalytic mechanism and photoelectrochemical selective sensing of Cu(2+) were also discussed.

Dendritic Tip-on Polytriazine-Based Carbon Nitride Photocatalyst with High Hydrogen Evolution Activity

“…Five layers of PTI-0 led to a bandgap of 4.4 eV, sufficient to represent that of the bulk material, confirming the influence of the packing to narrow the corresponding bandgap. 58 Figure 3 presents the band positions for the five-layer slab of PTI-0 and TAP-doped PTI monolayers. Using a monolayer configuration, the calculation revealed a bandgap reduction by 0.6 eV by PTI-0.143 with respect to PTI-0.…”

“…The calculations revealed a 0.48 eV increase in bandgap upon exfoliation to the monolayer, consistent with the trend of the measured values. 58 Following a single point calculation on one non-optimized layer in the bulk structure, it was determined that this effect is almost entirely electronic and unrelated to the relaxation of the atomic positions. Five layers of PTI-0 led to a bandgap of 4.4 eV, sufficient to represent that of the bulk material, confirming the influence of the packing to narrow the corresponding bandgap.…”

Candida rugosa lipase covalently immobilized on facilely-synthesized carbon nitride nanosheets as a novel biocatalyst

“…19 Although the characteristic absorption peaks of free CRL were highly overlapped with the absorption peaks of C 3 N 4 -NS, peaks could also be revealed due to CRL and C 3 N 4 -NS in the curve of C 3 N 4 -NS@CRL. These results suggest that the whole immobilization process could make sure that the basic structure of carbon nitride nanosheets was intact.…”

“…Meanwhile, the later dominant peak (2q ¼ 27 ) originated from the (002) interlayer diffraction of graphitelike layered structures. 19 The slight weakening of the characteristic peaks of C 3 N 4 -NS compared to the C 3 N 4 samples suggested that the interlayer stacking pattern of C 3 N 4 and the planar size of C 3 N 4 layers were weakened during the exfoliation process. Meanwhile, the characteristic diffraction angles of glutaraldehyde-modied C 3 N 4 -NS (G-C 3 N 4 -NS) and C 3 N 4 -NS@CRL exhibited no obvious difference to C 3 N 4 -NS, indicating that C 3 N 4 -NS retained its specic crystal texture and could ensure the mass transfer on the surface of C 3 N 4 -NS@CRL during catalytic reactions.…”

“…Among them, the binding energy peak at 283.6 eV was ascribed to characteristic sp 2 C-C and N-C]N bonds, and the binding energy peak at 286.8 eV was attributed to C-OR and O-C]O bonds. 19 Aer C 3 N 4 -NS was modied by glutaraldehyde or equipped with CRL, a new peak at 285 eV appeared, which could be attributed to sp 2 …”