Synthesis, characterization, and environmental evaluation of Fe-PCN-134:
A mixed linker metalloporphyrin MOF for the degradation of atrazine via
visible photo-Fenton reaction
Abstract
The irrational application of herbicides has led to severe water
contamination by atrazine and other pesticides. To solve this issue, a
mixed-linker metal-organic framework (MOF) photo-Fenton catalyst,
Fe-PCN-134, was prepared and evaluated for atrazine degradation in
water. Fe-PCN-134 could degrade atrazine up to 99.41% in
~80 min and could be used stably for four cycles.
Atrazine degradation conformed to pseudo-first-order kinetics, with a
rate constant ~103 times that of
Fe(III)tetrakis(4-carboxyphenyl)porphyrin chloride. In the mixed
junction MOF, the introduction of tetrakis(4-carboxyphenyl)porphyrin and
Fe3+ coordination could reduce the material bandgap, improving the
separation and transport efficiencies of photogenerated electron-hole
pairs. Further, the material could undergo a Fenton reaction during the
photocatalytic reaction, ultimately producing h+, ·OH, ·O2− and 1O2 and
thereby accelerating atrazine degradation. The safety and feasibility of
using Fe-PCN-134 in pesticide-contaminated water treatment have been
demonstrated by testing the plant and cell toxicity of the water after
the photo-Fenton treatment.