Synthesis of iron phthalocyanine/CeO2 Z-scheme nanocomposites as efficient photocatalysts for degradation of 2,4-dichlorophenol.

Modulating the photogenerated electrons of CeO2 to activate O2 and efficiently photocatalytic degra- dation of chlorophenols is a highly desired goal. Herein, we have successfully fabricated an 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 that by pure CeO2. By means of electron paramagnetic resonance (EPR) and single wavelength photocurrent spec- troscopy, it is confirmed that the excellent photocatalytic performance is mainly attributed to the for- mation of the Z-scheme heterojunction, which promotes charge separation and transfer, and the intro- duction of FePc broadens the visible light absorption range of the heterojunction. Moreover, O2 tempera- ture-programmed-desorbed curves and electrochemical O2 reduction measurement 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/MS), a possible reaction pathway of 2,4-DCP degradation was proposed. This study provides a novel strategy for preparing CeO2 based Z-scheme heterojunctions with abundant monoatomic sites for pollutant degradation. [ABSTRACT FROM AUTHOR]