In-situ electrodeposition synthesis of Z-scheme rGO/g-C3N4/TNAs photoelectrodes and its degradation mechanism for oxytetracycline in dual-chamber photoelectrocatalytic system

Enhanced visible light photocatalytic performance of carbon and oxygen co-doped carbon nitride with a three-dimensional structure: Performance and mechanism study

As a cost-effective photocatalyst, carbon nitride (g-C3N4) holds tremendous promise for addressing energy shortages and environmental pollution. However, its application is limited by disadvantages such as low specific surface area and easy recombination of photogenerated electron-hole pairs. This study introduces C and O co-doped g-C3N4 with a three-dimensional (3D) structure achieved through a straightforward one-step calcination process, demonstrating excellent photocatalytic activity of hydrogen production and oxytetracycline degradation, with superoxide radicals as the primary active species. We propose a plausible enhanced mechanism based on systematic characterizations and density functional theory calculations. The 3D structure confers a substantial specific surface area, enhancing both the adsorption area and active sites of catalysts while bolstering structural stability. Co-doping optimizes the band structure and electric conductivity of the catalyst, facilitating rapid migration of photogenerated charges. The synergistic effects of these enhancements significantly elevate the photocatalytic performance. This study presents a convenient and feasible method for the preparation of dual-regulated photocatalysts with outstanding performance.

Design strategies and mechanisms of g-C3N4-based photoanodes for photoelectrocatalytic degradation of organic pollutants in water

Emerging photoelectrocatalytic (PEC) systems integrate the advantages of photocatalysis and electrocatalysis and are considered as a promising technology for solving the global organic pollution problem in water environments. Among the photoelectrocatalytic materials applied for organic pollutant degradation, graphitic carbon nitride (CN) has the combined advantages of environmental compatibility, stability, low cost, and visible light response. However, pristine CN has disadvantages such as low specific surface area, low electrical conductivity, and high charge complexation rate, and how to improve the degradation efficiency of PEC reaction and the mineralization rate of organic matter is the main problem faced in this field. Therefore, this paper reviews the progress of various functionalized CN used for PEC reaction in recent years, and the degradation efficiency of these CN-based materials is critically evaluated. First, the basic principles of PEC degradation of organic pollutants are outlined. Then, engineering strategies to enhance the PEC activity of CN (including morphology control, elemental doping, and heterojunction construction) are focused on, and the structure-activity relationships between these engineering strategies and PEC activity are discussed. In addition, the important role of influencing factors on the PEC system is summarized in terms of mechanism, to provide guidance for the subsequent research. Finally, suggestions and perspectives are provided for the preparation of efficient and stable CN-based photoelectrocatalysts for practical wastewater treatment applications.