Co2+-loaded periodic mesoporous aluminum phosphonates for efficient modified Fenton catalysis

Abstract

Periodic mesoporous aluminum phosphonate (PMAP) materials with homogeneously integrated organophosphonate bridging groups inside the hybrid framework were synthesized by an autoclaving process using ethylene diamine tetra(methylene phosphonic acid) as the coupling molecule, with the assistance of the cationic surfactant cetyltrimethylammonium bromide. The prepared aluminum phosphonates possessed a high specific surface area of 511 m² g⁻¹ and a typical hexagonal mesophase, thus guaranteeing the considerable uptake capacity for loading Co²⁺ ions through coordination interaction. The monolayered adsorption behavior of Co²⁺ was confirmed, and the Co²⁺-loaded PMAP could be further utilized as a heterogeneous catalyst for oxidizing decomposition of phenol in the presence of peroxymonosulfate, with favorable kinetic and thermodynamic characteristics. It is suggested that the functionalities of metal phosphonate organic–inorganic hybrids could be rationally designed by judiciously selecting precursors and post-modification, making them potentially applicable in environmental remediation and catalysis.