Electrostatic self-assembly synthesized Fe-MOF/g-C3N4 S-scheme heterojunction for enhanced photocatalytic pollutant degradation

Abstract

Water-borne organic pollutants pose severe threats to human health, driving urgent demand for cost-effective, high-efficiency photocatalysts. In this work, a novel S-scheme heterojunction Fe-MOF/g-C₃N₄ photocatalyst is prepared through facile self-assembly. The porous composite exhibits a specific surface area of 97.414 m² g⁻¹, providing abundant active sites. The optimized MCN3-10 composite (Fe-MOF : g-C₃N₄ = 3 : 10) demonstrates exceptional activity, achieving 99% rhodamine B (RhB) degradation under xenon lamp irradiation within 40 minutes. Its first-order rate constant (120.33 × 10⁻³ min⁻¹) represents 33.9-fold and 2.5-fold enhancements over pristine Fe-MOF and g-C₃N₄, respectively. The superior performance originates from the S-scheme heterojunction, which simultaneously enhances redox capabilities and facilitates efficient charge carrier separation, resulting in the production of abundant reactive species for pollutant degradation.