In Situ Reduction-Generated Ag⁰ Plasmonic Sites on Ti₃C₂/Ag₂NCN Schottky Heterojunctions for Efficient Photocatalytic...

Constructing Schottky heterojunctions with plasmonic components offers a promising route to enhance photocatalytic performance, yet the synergistic roles of the Schottky barrier and localized surface plasmon resonance (LSPR) in pollutant degradation remain insufficiently elucidated. Herein, a series of Ti₃C₂/Ag-Ag₂NCN (TAN) composites with varied Ag loadings was prepared via an in situ precipitation-chemical reduction method. The pseudo-first-order rate constant of the TAN-30 heterojunction reached roughly 7.0 times the value of bare Ag₂NCN, while its tetracycline degradation efficiency under visible light reached 87.0% at 240 min. Moreover, the heterojunction exhibited outstanding reusability over five successive runs. Comprehensive characterizations reveal that the Schottky barrier at the Ti₃C₂/Ag₂NCN interface effectively suppresses photogenerated carrier recombination, while the LSPR effect of metallic Ag⁰ broadens the light absorption range and elevates the local surface temperature, synergistically accelerating charge migration. The dominance of h⁺ and •O₂^- among the reactive species was established by both radical trapping assays and ESR spectroscopic analysis. This work provides mechanistic insights into LSPR-enhanced Schottky heterojunctions and offers a rational design strategy for MXene-based photocatalysts toward efficient antibiotic wastewater treatment.