g-C₃N₄ synthesized from NH₄SCN in a H₂ atmosphere as a high performance photocatalyst for blue light-driven degradation of rhodamine B

Abstract

Graphitic carbon nitride (g-C3N4) was prepared by a simple thermal polymerization method in this work.

Influence of Hydrogenation on Morphology, Chemical Structure and Photocatalytic Efficiency of Graphitic Carbon Nitride

“…The isotherms curves of materials display the typical type IV isotherms and type H4 hysteresis loops, proving the formation of mesopores in the obtained samples. Each isotherm does not have clear saturated adsorption platforms, which indicates a very irregular pore structure [ 11 ]. The results revealed that annealing in the H 2 atmosphere caused an increase in specific surface area (SSA), total pore volume, and average pore diameter.…”

“…The C 1s region includes three peaks. Specifically, the peak at 284 eV belongs to a special sp 2 C–C bond in the CN from g-C 3 N 4 [ 11 ]. The peak at 286.5 eV is attributed to the C atom on the aromatic ring connected to NH x [ 11 ].…”

“…Moreover, the effects of the precursor and preparation conditions on the photocatalytic performance of g-C 3 N 4 were also studied [ 10 , 11 ]. For example, Tay et al [ 10 ] showed enhanced visible light absorption and photocatalytic H 2 evolution by introducing nitrogen vacancies in g-C 3 N 4 produced by direct thermal polymerization of dicyandiamide in H 2 atmosphere.…”

“…g-C 3 N 4 (H 2 ) shows ~5 times higher H 2 evolution with the assistance of visible light illumination compared to g-C 3 N 4 (air), confirming the importance of gas atmosphere during catalyst preparation. Zhang et al [ 11 ] studied the effect of precursor type, thermal polymerization temperature, and the atmosphere to achieve a highly effective catalyst based on g-C 3 N 4 . g-C 3 N 4 prepared from ammonium thiocyanate (AT, NH 4 SCN) as precursor at 550 °C for 5 h under H 2 atmosphere showed the highest activity.…”

“…The prepared sample showed good stability and reusability after four cycles. Evidence shows that controlling the effects of preparation conditions has played a crucial role in lowering the charge carrier recombination probability by shortening the diffusion length for boosted photocatalytic efficiency [ 5 , 6 , 11 , 12 ]. Therefore, the synergistic controlling of the band structure and the microstructure of g-C 3 N 4 is highly desirable but challenging [ 6 ].…”