C‐Doped g‐C ₃ N ₄ /MIL‐100(Fe) Heterojunction for Enhanced Photo‐Fenton Degradation of Ciprofloxacin

The charge separation efficiency of g‐C 3 N 4 /MOFs heterojunctions synthesized via conventional precursor methods remains limited, thereby limiting their photocatalytic performance. Utilizing glucose‐modified dicyandiamide as a monosource precursor, we created an isotype wherein the heterojunction was located at the interface of the g‐C 3 N 4 nanosheets and bulk g‐C 3 N 4 (referred to as C–C 3 N 4 ). A strategic synthesis protocol was subsequently developed to construct C–C 3 N 4 @MIL‐100(Fe) (CCM) via integration with MIL‐100(Fe). This hybrid configuration demonstrates two key functional advantages: (1) significant augmentation of the visible light harvesting capacity of C–C 3 N 4 and (2) formation of type I heterojunctions that effectively facilitate interfacial charge transfer and suppress photogenerated e–h + recombination. The enhanced photocatalytic activity of the material under visible light can be ascribed to the combined influence of these mutually reinforcing factors. The enhanced photo‐Fenton catalytic activity originated from three interdependent factors: (a) optimized interfacial contact between the components, (b) extended visible‐light absorption range, and (c) development of coordinated electron transfer pathways across the CCM interface. A mechanistic framework for ciprofloxacin degradation via the CCM photo‐Fenton system was elucidated employing a comprehensive analysis involving radical scavenger experiments and Mott–Schottky characterization.