Building step-scheme (S-scheme) heterojunctions has recently emerged as a highly effective approach for developing superior photocatalysts for water purification. Herein, a C3N5/ Ag3PO4 (CA) S-scheme heterojunction was prepared by in situ growth of Ag3PO4 nanoparticles on 2D C3N5 nanosheets. Notably, under visible-light irridiation, CA exhibited significantly higher activity in the photodegradation of LEVO, which is about 28.38, 2.41, and 2.14 times higher than the rates for C3N5, Ag3PO4, and the mixture, respectively. Based on the radical scavenging experiments, the mechanism for enhanced photocatalytic performance has been analyzed, is attributed to improved interfacial charge separation, the elevated redox potential of photon-generated electrons and holes, and the increased generation of active species resulting from the S-scheme transfer of photoinduced carriers. Additionally, CA demonstrates greater stability than either C3N5 or Ag3PO4 alone in the photo-oxidation of LEVO and the photodegradation of RhB. In essence, this study not only deepens our comprehension of the photocatalytic mechanism of CA, but also pioneers a novel concept for the development of highly effective and stable S-type heterojunction photocatalysts.

In situ construction of N-rich carbon nitride (C3N5)silver phosphate (Ag3PO4) S-scheme heterojunctions for the efficient photocatalytic removal of levofloxacin antibiotic and RhB
    Abstract
        Graphical abstract
    1 Introduction
    2 Experimental
        2.1 Preparation of samples
        2.2 Photocatalytic performance test
        2.3 Determination of the active species
    3 Results and discussion
        3.1 Catalyst preparation and characterization
        3.2 Photocatalytic activity and photostability
        3.3 The mechanism of improved photocatalytic performance
            3.3.1 BET surface area
            3.3.2 Charge separation and transfer kinetics
            3.3.3 Photocatalysis mechanism
    4 Conclusion
    References

• Xiaodong Liu(College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, Shandong, China)
• Yuanfei Li(College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, Shandong, China)
• Huanli Wang(College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, Shandong, China)
• Jiayuan Liu(College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, Shandong, China)
• Jingchuan Fu(College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, Shandong, China)
• Jia Liu(College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, Shandong, China)
• Shijie Li(National Engineering Research Center for Marine Aquaculture, Zhejiang Ocean University, Zhoushan 316022, Zhejiang, China)