Enhanced visible-light-driven photocatalytic performance of porous graphitic carbon nitride

Abstract

a b s t r a c tIn this study, a series of porous graphitic carbon nitride (g-C 3 N 4 ) materials were fabricated through a direct pyrolysis of protonated melamine by nitric acid solution. These as-prepared porous samples were characterized by a collection of analytical techniques. It was found that a proper concentration of nitric acid solution involved facilitated to generate samples in tube-like morphology with numerous pores, identified with X-ray diffraction patterns, FT-IR spectra, SEM, TEM, and BET measurements. These g-C 3 N 4 samples were subjected to photocatalytic degradation of dye Rhodamine B (RhB) in aqueous under visible-light irradiation. Under identical conditions, those porous g-C 3 N 4 samples showed significantly improved catalytic performance in comparison with the sample prepared without the introduction of nitric acid. In particularly, the best candidate, sample M1:1, showed an apparent reaction rate nearly 6.2 times that of the unmodified counterpart. The enhancement of photocatalytic performance could be attributed to the favorable porous structure with the enlarged specific surface area and the suitable electronic structure as well. In addition, ESR measurements were conducted for the sake of proposing a photocatalytic degradation mechanism.

Direct growth of uniform carbon nitride layers with extended optical absorption towards efficient water-splitting photoanodes

“…In the N 1s spectrum, three main peaks at 398.4, 399.9, and 401.0 eV were detected and assigned to sp 2 C-N=C bonds, the tertiary nitrogen N-(C) 3 groups, and the amino groups (C-NH-C and C-NH 2 ), respectively, while a peak at 403.9 eV was assigned to charging effects 33,40 . In the O 1s spectrum, a peak at 532.1 eV, due to adsorbed water, was observed 41 . The highresolution spectrum of S 2p shows the absence of sulfur in the final CN.…”

“…Under front-side illumination, not all the photogenerated electrons reach the FTO glass due to the large distance that the electrons should travel. A further increase in the film's thickness results in a decline in photocurrent, which probably stems from reduced light penetration within the electrode and increased electron-hole recombination within the active layer before they react 41 . In addition to the thickness, the influence of the calcination temperature during the preparation of the CN T electrode on its morphology and PEC characteristics were also explored (Supplementary Figs.…”

g‐C3N4‐Based Heterostructured Photocatalysts

“…[288][289][290] Photocatalysis has been demonstrated effective for the deg radation of environmental pollutants, including organic and inorganic air pollutants, [168,212] toxic dyes, [50,89,220,291] phenol and persistent organic micropollutants in water. Photocatalysis has proven to be a promising strategy for environmental decontamination due to its high efficiency and low cost.…”

Characterization of urea derived polymeric carbon nitride and resultant thermally vacuum deposited amorphous thin films: Structural, chemical and photophysical properties

“…The p-CN only consists of abundant elements in a tri-s-triazine ring structure as elementary building block. It can be synthesized via a straightforward and scalable process from relatively cheap source materials such as dicyandiamide [10][11][12][13][14][15][16][17][18], cyanamide [19], ammonium thiocyanate [20], melamine [21][22][23][24][25][26][27][28][29][30], urea [8,9,[31][32][33][34][35][36], thiourea [28], guanidine carbonate [37] and thiosemicarbazide [38]. Generally, synthesis methods of p-CN involve thermal treatment of precursor material in the temperature range of 450-650 °C.…”