Efficient Sunlight Degradation of Wide‐Spectrum Antibiotics Through Enhanced Charge Separation in SnTCPP NPs‐Nb 2 C Schottky Heterojunction: Ultrafast Carrier Dynamic Study

ABSTRACT To leverage the synergistic benefits of sunlight‐responsive metalloporphyrin complexes and conductive MXene materials, a Schottky heterojunction comprising tin‐porphyrin (SnTCPP) nanoparticles (NPs) and Nb 2 C MXene was rationally constructed. Notably, the SnTCPP NPs‐Nb 2 C Schottky heterojunctions demonstrate exceptional sunlight‐driven catalytic activity toward tetracycline antibiotics and ofloxacin degradation, achieving a removal efficiency of up to 99.9% within 60 min of irradiation in both model wastewater and natural water. The unique energy structure of SnTCPP NPs‐Nb 2 C facilitates rapid charge transfer while inhibiting the recombination of photogenerated carriers, thereby enhancing the generation of reactive oxygen species, such as holes and superoxide anion radicals, which are the key factors driving tetracycline antibiotics and ofloxacin degradation. Ultrafast spectroscopic results unveil efficient Schottky junction‐mediated ultrafast charge transfer and separation at the SnTCPP NPs‐Nb 2 C interface. The integrated DFT and liquid chromatography‐mass spectrometry demonstrated the sequential cleavage of tetracycline's functional groups, including the dimethylamino group, phenolic moiety, and tetracyclic ring structure, ultimately leading to the mineralization of tetracycline into harmless small molecules. Notably, the high degradation efficiency can be maintained over multiple consecutive recycling cycles without significant loss of catalytic activity. These studies pave the way for the rational design of next‐generation sunlight‐driven heterojunction catalysts for environmental pollutant remediation.