• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.28-51
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• 2018

Graphitic carbon nitride ($g-C_3N_4$) as a fascinating visible light active semiconductor photocatalyst has medium band gap, non-toxic nature, stable chemical structure and high thermal stability. Recently, intensive researches are focused on photocatalytic activity of $g-C_3N_4$ for wastewater treatment. This review demonstrates latest progress in fabrication of graphitic carbon nitride $C_3N_4$ incorporated nanocomposite to explore photocatalytic ability for water purification. The $g-C_3N_4$-based nanocomposites were categorized as $g-C_3N_4$ metal-free nanocomposite, noble metals/$g-C_3N_4$ heterojunction, non-metal doped $g-C_3N_4$, transition and post transition metal based $g-C_3N_4$ nanocomposite. Apart from fabrication methods, we emphasized on elaborating the mechanism of activity enhancement during photocatalytic process.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.627-634
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• 2023

Graphitic carbon nitride (g-C₃N₄) has attracted considerable attention since its discovery for its catalysis of water splitting to hydrogen and oxygen under visible light irradiation. However, pristine g-C₃N₄ confers only low photocatalytic efficiency and requires surface cocatalysts to reach moderate activity due to a lack of accessible surface active sites. Inspired by the high specific surface area and superior electron transfer of graphene, we developed a strongly coupled binary structure of graphene and g-C₃N₄ aerogel with 3D porous skeleton. The as-prepared 3D structure photocatalysts achieve a high surface area that favors efficient photogenerated charge separation and transfer, enhances the light-harvesting efficiency, and significantly improves the photocatalytic hydrogen evolution rate as well. The photocatalyst performance is observed to be optimized at the ratio 3:7 (g-C₃N₄:GO), leading to photocatalytic H₂ evolution of 16125.1 mmol. g^-1. h^-1 under visible light irradiation, more than 161 times higher than the rate achieved by bulk g-C₃N₄.

• Journal of Adhesion and Interface
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• v.15 no.2
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• pp.63-68
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• 2014

Hollow mesoporous carbon nitride material with sphere shape was synthesized using polystyrene sphere as template and cyanamide as nitrogen and carbon atom sources via thermal treatment process. The process of the silica removal is not necessary because silica as template is not in use for the synthesis of hollow mesoporous carbon nitride material and any solvents are also not in use. The size of polystyrene spheres was about 170 nm. Hollow diameter and wall thickness were 82 nm and 13 nm, respectively, in hollow mesoporous carbon nitride sphere. Surface area, mesopore size and pore volume of hollow mesoporous carbon nitride material was $188m^2g^{-1}$, 3.8 nm and $0.35cm^3g^{-1}$, respectively. The wall in hollow sphere has graphitic structure. Hollow mesoporous carbon nitride material has potential applications in the area of fuel cell, catalysis, photocatalysis, electroemmision device, etc.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.4 no.2
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• pp.115-120
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• 2018

In recent years, many researchers have attempted to make use of 2D nanoparticles as molecular imaging probes since extensive investigations proved that 2D nanoparticles in the body tends to accumulate certain lesions by enhanced permeability and retention (EPR) effect. For example, graphene and carbon nitride which have high surface area and modifiable properties showed good biocompatibility and targetability when it used as imaging probes. However, poor dispersibility in physiological mediums and its uncontrolled size limited its usage in bio-application. Therefore, oxidation process and mechanical exfoliation have been developed for overcoming these problems. In this paper, we highlight the several major methods to synthesize biocompatible 2D nanomaterials like graphene and carbon nitride especially for molecular imaging study including positron emission tomography (PET).

• Elastomers and Composites
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• v.59 no.1
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• pp.1-7
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• 2024

Nanorod graphitic carbon nitride (g-C₃N₄) was synthesized by reacting melamine (C₃H₆N₆) with trithiocyanuric acid (C₃H₃N₃S₃) in distilled water for 10 h at room temperature. The resulting mixture was calcined at 550℃ for 2 h in an electric furnace under an air atmosphere. Nanorod g-C₃N₄/Ag₃PO₄ composites were prepared by adding nanorod graphitic carbon nitride (g-C₃N₄) powder, silver nitrate (AgNO₃), ammonia (NH₃·H₂O, 25.0-30.0%), and sodium hydrogen phosphate (Na₃HPO₄) to distilled water. The samples were characterized via X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy. The photocatalytic activities of the nanorod g-C₃N₄/Ag₃PO₄ composites were demonstrated via the degradation of organic dyes, such as methylene blue and methyl orange, under blue light-emitting diode irradiation and evaluated using UV-vis spectrophotometry.

• Archives of Metallurgy and Materials
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• v.65 no.3
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• pp.1111-1116
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• 2020

Graphitic carbon nitride (g-C₃N₄) is an attractive photocatalyst, however, its practical photocatalytic applications are still faced with huge challenges. The aim of this research is to identify the correlation between synthetic conditions and properties of the g-C₃N₄ and derive an optimum synthesis condition for improving photocatalytic activities of the g-C₃N₄. In this study, novel and versatile g-C₃N₄ nanosheets were synthesized by the simple thermal pyrolysis of urea. In the synthesis process, the pyrolysis temperature and the heating rate, which can have the most significant influence on the structures and properties of g-C₃N₄, were set as variables, and the effects were systematically investigated. When synthesized at a relatively high temperature, the amount of material being synthesized is reduced, however it has been found to represent optical properties suitable for highly efficient photo-catalyst by the increase in the thickness and defects formed in the g-C₃N₄ nanosheets. The photocatalytic degradation experiment of MB dyes indicated that the highest degradation of 95.2% after the reaction for 120 min was achieved on the g-C₃N₄ nanosheets synthesized at 650℃.

• Journal of the Korean GEO-environmental Society
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• v.24 no.3
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• pp.23-27
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• 2023

Graphitic carbon nitride (g-C₃N₄) has been used as effective photocatalyst for degradation of antibiotics under visible light irradiation. However, the fast recombination of hole-electron pair may limit their photocatalytic efficiency. In our study, Ag was grafted on g-C₃N₄/g-C₃N₄ isotype heterojunction by a microwave-assisted decomposition method. The structure and physical properties of heterojunction photocatalyst were characterized through X-ray diffraction, UV-DRS, FT-IR, and Photoluminescence analyses. Ag decorated g-C₃N₄/g-C₃N₄ isotype heterojunction exhibited excellent photocatalytic activity for degradation of sulfamethoxazole under irradiation under visible light irradiation within 210 min, which is higher than g-C₃N₄/g-C₃N₄ isotype heterojunction and bulk g-C₃N₄. The addition of Ag may broaden the visible light absorption and restrict the recombination of hole-electron pair because of the surface plasmons resonance, resulting in the improving the photocatalytic activity.

• Textile Coloration and Finishing
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• v.30 no.2
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• pp.63-69
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• 2018

In this study, we report on successful attempt towards the synthesis of sulfur self-doped $g-C_3N_4$ by directly heating thiourea in air. The synthesized materials were characterized using UV-vis spectral technique, FT-IR, XRD and TEM analysis. Further, the obtained material shows an excellent detection of carcinogenic TNP(Tri nitro phenol) in the presence of 10-fold excess of various other common interferences. The strong inner filter effect and molecular interactions(electrostatic, ${\pi}-{\pi}$, and hydrogen bonding interactions) between TNP and the $S-g-C_3N_4$ Nano sheets led to the fluorescence quenching of the $S-g-C_3N_4$ Nano sheets with an excellent selectivity and sensitivity towards TNP compared to that of other nitro aromatics under optimal conditions and the detection limit calculated was found to be 6.324 nM for TNP. The synthesized nanocomposite provides a promising platform for the development of sensors with improved reproducibility and stability for ultra-sensitive and selective sensing of TNP.

• Advances in materials Research
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• v.11 no.3
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• pp.225-235
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• 2022

It includes the synthesis of pristine ZnO nanoparticles and a series of Ag-doped zinc oxide nanoparticles was carried out by reflux method by varying the amount of silver (1, 3, 5, 7 and 9% by mol.). The morphology of these nanoparticles was investigated by SEM, XRD and FT-IR techniques. These techniques show that synthesized particles are homogenous spherical nanoparticles having an average particle size of about 50-100 nm along with some agglomeration. The photocatalytic activity of the ZnO nanoparticles and Ag doped ZnO nanoparticles were investigated via photodegradation of methylene blue (MB) as a standard dye. The data from the photocatalytic activity of these nanoparticles show that 7% Ag-doped ZnO nanoparticles exhibit much enhanced photocatalytic activity as compared to pristine ZnO nanoparticles and other percentages of Ag-doped ZnO nanoparticles. Furthermore, 7% Ag-doped ZnO was made composites with sulfur-doped graphitic carbon nitride by physical mixing method and a series of nanocomposites were made (3.5, 7.5, 25, 50, 75% by weight). It was observed that the 25% composites exhibited better photocatalytic performance than pristine S-g-C 3 N 4 and pure 7% Ag-doped ZnO. Tauc's plot also supports the photodegradation results.

• Journal of the Microelectronics and Packaging Society
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• v.31 no.2
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• pp.78-84
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• 2024

The electrochemical reduction of carbon dioxide (CO₂) is gaining attention as an effective method for converting CO₂ into high-value carbon compounds. This paper reports a facile meth od for synth esizing and characterizing g-C₃N₄-modified porous Au (pAu) electrodes for electrochemical CO₂ reduction using e-beam deposition and anodization techniques. The fabricated pAu@g-C₃N₄ electrode (@ -0.9 VRHE) demonstrated superior electrochemical performance compared to the pAu electrode. Both electrodes exhibited a Faradaic efficiency (FE) of 100% for CO production. The pAu@g-C₃N₄ electrode achieved a maximum CO production rate of 9.94 mg/s, which is up to 2.2 times higher than that of the pAu electrode. This study provides an economical and sustainable approach to addressing climate change caused by CO₂ emissions and significantly contributes to the development of electrodes for electrochemical CO₂ reduction.