The heterojunction photocatalyst nitrogen-deficient g-C₃N₄/BiOCl (CNBOC) was synthesized via in-situ calcination coupled with hydrothermal methods. Under visible-light irradiation (λ > 510 nm), the CNBOC-2 composite demonstrated enhanced photocatalytic activity for tetracycline hydrochloride (TC) degradation, achieving 86.2% removal within 60 min. The composite also exhibited excellent cycling stability, retaining ~70% degradation efficiency after four successive cycles. Photoluminescence (PL) characterization revealed that the nitrogen-deficient g-C₃N₄ upconversion agent effectively absorbed near-infrared light (~850 nm) and emitted yellow-green light (~570 nm).

Weiyang Chen, Jingjing Xu. Enhancing Tetracycline Degradation through Nitrogen-Deficient G-C3N4/BiOCl Heterojunction with Upconversion Photocatalysis. Academic Journal of Materials & Chemistry (2025), Vol. 6, Issue 3: 19-29. https://doi.org/10.25236/AJMC.2025.060302.

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