The coordination bond reinforced FeOCl/C3N4 heterostructure for photocatalytic degradation of persistent organic pollutants

Persistent organic pollutants (POPs) present a substantial environmental challenge due to their enduring nature and adverse effects on human health. The exploration of photocatalysts featuring abundant active sites and appropriate band structures represents a promising approach for harnessing solar energy in photo-self-Fenton reactions for pollutant oxidation. In this investigation, a two-dimensional S-scheme FeOCl/C3N4 heterostructure was fabricated for the degradation of POPs. The coordination between dangling nitrogen atoms in C3N4 and Fe3+ in FeOCl established a novel pathway for the transfer of photogenerated electrons, thereby prolonging their lifespan by mitigating recombination events. Assessment of the photocatalytic performance using 4-chlorophenol (4-CP) as a model pollutant revealed a 5.4-fold and 40-fold enhancement in degradation rate over FeOCl/C3N4 compared to individual catalysts. Notably, nearly complete mineralization rates were achievable with FeOCl/C3N4, underscoring its robustness. Mechanistic investigations delineated hydroxyl radicals (center dot OH) as the primary active species responsible for pollutant degradation.