Controllable synthesis of Fe5(PO4)4(OH)3·2H2O as a highly efficient heterogeneous Fenton-like catalyst

Abstract

Fe₅(PO₄)₄(OH)₃·2H₂O has been successfully synthesized by a simple hydrothermal process. The effects of hydrothermal temperature and pH value on the morphologies and sizes of the Fe₅(PO₄)₄(OH)₃·2H₂O particles were investigated. The Fe₅(PO₄)₄(OH)₃·2H₂O photocatalyst showed lower photocatalytic activity for the degradation of methylene blue under visible light irradiation. But the heterogeneous Fenton-like Fe₅(PO₄)₄(OH)₃·2H₂O with H₂O₂ showed highly efficient photocatalytic activity in the photocatalytic decomposition of methylene blue. Effective electron transfer from the visible light-excited dyes to Fe(III), which leads to regeneration of Fe(II) and an easy cycle of Fe(III)/Fe(II), results in much faster degradation and mineralization of methylene blue in the photo-Fenton reaction under visible light irradiation.