Synthesis of Iron Phthalocyanine/CeO2 Z-scheme nanocomposites as efficient photocatalysts for degradation of 2, 4-chlorophenol

Modulating the photogenerated electrons of CeO2 to activate O2 and efficiently photocatalytic degradation of chlorophenols is a highly desired goal. Herein, we have successfully fabricated FePc/CeO2 heterojunction through H-bond induced assembly. The photocatalytic degradation of 2, 4-DCP by the amount-optimized FePc/CeO2 nanocomposite was improved by 3 times compared with pure CeO2. By means of electron paramagnetic resonance (EPR) and single wavelength photocurrent spectroscopy, it is confirmed that the excellent photocatalytic performance is mainly attributed to the formation of Z-scheme heterojunction, which promotes charge separation and transfer, and the introduction of FePc broadens the visible light absorption range of heterojunction. Moreover, O2 temperature-programmed-desorbed curves and electrochemical O2 reduction measurements results demonstrate that the single Fe-N4(II) site in FePc is more conducive to promoting O2 activation than that of other metal phthalocyanines. Based on in situ FT-IR and liquid chromatography-tandem mass spectrometry (LC-MS), a possible reaction pathway of 2, 4-DCP degradation was proposed. This study provides a novel strategy to prepare CeO2 based Z-scheme heterojunctions with abundant monoatomic sites for pollutant degradation.