Interfacial chemical bonding in 2D/2D NiFe-LDH/C3N4 Z-type heterojunction for enhanced photocatalytic degradation of antibiotics

This study addressed the critical need for antibiotic pollution control in industrial wastewater by successfully constructing a two-dimensional/two-dimensional NiFe-LDH/C 3 N 4 Z-type heterojunction photocatalyst with strong chemical bonding through an innovative interfacial chemical engineering strategy. Thermal activation was used to expose N active sites on the C 3 N 4 surface, and in-situ growth of NiFe-LDH nanosheets was achieved via co-precipitation. Stable Ni-N and Fe-N coordination bonds were constructed at the heterojunction interface, forming an efficient interfacial charge transport channel that significantly suppressed the recombination of photogenerated carriers. Material characterization showed that the catalyst possessed a broadened visible light response, enhanced specific surface area, and optimized charge separation efficiency. Photocatalytic experiments demonstrated excellent degradation performance for fluoroquinolone antibiotics such as norfloxacin, ciprofloxacin, and ofloxacin. Norfloxacin achieved a 90% removal rate within 120 minutes, with good cycling stability. Mechanistic studies revealed that the degradation process is primarily driven by superoxide radicals (·O 2 - ). This work not only proposed a novel method for constructing heterostructures through "surface active site design and in-situ interface bonding", but also experimentally revealed the key role of interfacial chemical bonding in regulating band structure, promoting charge separation and enhancing material stability, providing important theoretical and practical basis for the rational design of efficient and stable photocatalytic materials under the guidance of surface and interface science.