Electron self-sufficient core-shell BiOCl@Fe-BiOCl nanosheets boosting Fe(III)/Fe(II) recycling and synergetic photocatalysis-Fenton for enhanced degradation of phenol

Core-shell BiOCl@Fe-BiOCl nanosheets with electron self-sufficient structure were prepared as catalysts to promote degradation and mineralization of phenol through synergetic photocatalysis-Fenton. This electron self-sufficient structure was established by engaging a strong internal electric field of BiOCl core and electron-capture centers of doped Fe(III) in Fe-BiOCl shell for electrons supplying and consuming, respectively, separating charges spatially and enriching holes on the surface of catalysts. Meanwhile, the Fe(III) transited to Fe(II), which acted as reactive sites for H2O2 activation and was further reversed to Fe(III) and hydroxyl radical (•OH) through Fenton reaction, achieving Fe(III)/Fe(II) recycling. The •OH and surface holes could synergistically boost the degradation and mineralization (∼64 %) of phenol. The reaction rate constant of BiOCl@Fe-BiOCl nanosheets was ∼41.32 and ∼95 times higher than that of BiOCl under full spectra and visible light irradiation, respectively. This work provides sophisticated structure design of catalysts, boosting Fe(III)/Fe(II) recycling, catalytic activity, and mineralization.