Synthesis Of Carbon Nitride Nanosheets Research Articles

Synthesis of carbon nitride nanosheets with N vacancies boosted by S doping for photocatalytic efficient killing of E. coli under visible light

To address the problem of bacterial contamination in drinking water, we synthesized non-metallic photocatalysts for the inactivation of Escherichia coli in drinking water. In this paper, S-g-C3N4 (S-g-CN) composite nanomaterials were synthesized via a one-step calcination method. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and transmission electron microscopy (TEM) analyses confirmed the successful synthesis of S-g-CN with N vacancies. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy analyzed the layered morphology and chemical structure of g-C3N4 before and after modification. Optical characterization revealed significantly enhanced light absorption, electron-hole separation efficiency, and carrier mobility in the modified samples. Bactericidal assays demonstrated that under visible light, 0.3 % S-g-CN nanomaterials exhibited superior bactericidal effects against E. coli compared to unmodified g-C3N4. Furthermore, 0.3 % S-g-CN demonstrated excellent degradation of Rhodamine B (RhB) under various conditions (pollutant concentration, pH, and catalyst dosage). Recyclability studies over three cycles confirmed the catalyst's stability and reusability.

Synthesis of Carbon Nitride Nanosheets with n→π* Electronic Transition for Boosting Photocatalytic CO2 Reduction

Awakening n→π* electronic transition in graphitized carbon nitride can extend the visible light absorption range of the original g-C3N4, which will contribute to improve the photocatalytic activity of carbon dioxide reduction. Here we report that the n→π* transition in g-C3N4 is activated by the cooperation of steam etching and alkali treatment. The CO and CH4 evolution yields of the NaOH/Vc‐CN sample are 4.3 and 16 times higher than those of original g-C3N4, respectively. The planar asymmetry structure of heptazine was fabricated due to the hydroxyl groups reacting with terminal N-H content produced by the construction of carbon vacancy and the Na+ ions insert into the interlayer. Therefore, n→π* electronic transition in g-C3N4 was awakened, extending the optical absorption range with light wavelengths longer than 470 nm. At the same time, the ability of CO2 chemisorption and activation was improved due to the NaOH modification. Therefore, the extended visible light absorption, the improved crystallinity and the increased active sites are beneficial to optimizing the utilization efficiency of photogenerated carriers and enhancing photocatalytic activity.

One-Step Synthesis of Carbon Nitride Nanosheets for Photoremediation of Toxic Organic Dyes Waste in Aquatic Environment

Graphitic Carbon nitride ( g-C 3 N 4 ) has been taking the attention of scientists because of its potential applications as a catalyst for organic synthesis, electrodes, photocatalyst, and hydrogen storage material. The g-C 3 N 4 has also excellent chemical stability, special optical characteristics, and high thermal stability. Moreover, it only consists of carbon and nitrogen elements that make it safer for the environment than metal-based catalysts. Various techniques have been introduced to improve g-C 3 N 4 photocatalytic efficiency as a combination with other semiconductors and the modification of morphology like porous g-C 3 N 4 or nanostructures g-C 3 N 4 . When compared with g-C 3 N 4 bulk, g-C 3 N 4 Nanosheets have many advantages including high efficiency, low cost, environmentally friendly, and easy to produce on a large scale. This review contains an overview of the one-step synthesis method from melamine and ammonium chloride for g-C 3 N 4 nanosheets as well as characteristics and potential applications in dyes photoremediation.

Synthesis of carbon nitride nanosheets with tunable size by hydrothermal method for tetracycline degradation

Tunable size graphitic carbon nitride (g-C3N4) nanosheets with the thickness of 10–20 nm were synthesized through hydrothermal method by employing melamine and cyanuric acid as precursors and followed calcination processes. The size of g-C3N4 nanosheets can be controlled from 100 to 300 nm to several micrometers by simply adjusting the ratio of melamine and cyanuric acid. The analysis shows that the obtained small-size g-C3N4 nanosheets exhibit a larger band gap and improved photogenerated electron-hole pairs separate efficiency compared with that of the large-size nanosheets. Due to synergistic effects of broader band gap and high separation efficiency, small-size g-C3N4 nanosheets show excellent performance for tetracycline degradation. This work provides some new insights for the rational design and synthesis of tunable size g-C3N4 nanosheets photocatalysts with high efficiency.