Magnetically separable photocatalyst of direct Z-scheme g-C3N4 nanosheets/natural hematite ore hybrids

Recent advances in g-C3N4-based photocatalysis for water treatment: Magnetic and floating photocatalysts, and applications of machine-learning techniques

Over the past decade, there has been a substantial increase in research investigating the potential of graphitic carbon nitride (g-C3N4) for various environmental remediations. Renowned for its photocatalytic activity under visible light, g-C3N4 offers a promising solution for treating water pollutants. However, traditional g-C3N4-based photocatalysts have inherent drawbacks, creating a disparity between laboratory efficacy and real-world applications. A primary practical challenge is their fine-powdered form, which hinders separation and recycling processes. A promising approach to address these challenges involves integrating magnetic or floating materials into conventional photocatalysts, a strategy gaining traction within the g-C3N4-based photocatalyst arena. Another emerging solution to enhance practical applications entails merging experimental results with contemporary computational methods. This synergy seeks to optimize the synthesis of more efficient photocatalysts and pinpoint optimal conditions for pollutant removal. While numerous review articles discuss the laboratory-based photocatalytic applications of g-C3N4-based materials, there is a conspicuous absence of comprehensive coverage regarding state-of-the-art research on improved g-C3N4-based photocatalysts for practical applications. This review fills this void, spotlighting three pivotal domains: magnetic g-C3N4 photocatalysts, floating g-C3N4 photocatalysts, and the application of machine learning to g-C3N4 photocatalysis. Accompanied by a thorough analysis, this review also provides perspectives on future directions to enhance the efficacy of g-C3N4-based photocatalysts in water purification.

NGQD active sites as effective collectors of charge carriers for improving the photocatalytic performance of Z-scheme g-C3N4/Bi2WO6 heterojunctions

NGQDs as effective active sites and collectors of charge carriers in Z-scheme g-C₃N₄/Bi₂WO₆ heterojunctions.

Regenerable g-C3N4–chitosan beads with enhanced photocatalytic activity and stability

In this study, a series of regenerable graphitic carbon nitride–chitosan (g-C₃N₄–CS) beads were successfully synthesized via the blend crosslinking method. The prepared beads were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The structural characterization results indicate that the g-C₃N₄ granules were uniformly distributed on the surface of the chitosan matrix, and the structures of g-C₃N₄ and CS are maintained. In addition, the prepared g-C₃N₄–CS beads exhibited efficient MB degradation and stability. The optimum photocatalytic activity of our synthesized g-C₃N₄–CS beads was higher than that of the bulk g-C₃N₄ by a factor of 1.78 for MB. The improved photocatalytic activity was predominantly attributed to the synergistic effect between in situ adsorption and photocatalytic degradation. In addition, the reacted g-C₃N₄–CS beads can be regenerated by merely adding sodium hydroxide and hydrogen peroxide. Additionally, the regenerated g-C₃N₄–CS beads exhibit excellent stability after four runs, while the mass loss is less than 10%. This work might provide guidance for the design and fabrication of easily regenerated g-C₃N₄-based photocatalysts for environmental purification.

In this study, a series of regenerable graphitic carbon nitride–chitosan (g-C₃N₄–CS) beads were successfully synthesized via the blend crosslinking method.