Hetero-metal MOF derivatives anchored on porous carbonized wood as photo-Fenton catalysts for ultrafast organic pollutant removal

Abstract

Hetero-metal organic framework (HMOF) derivatives have emerged as promising photo-Fenton catalysts for removing hazardous organic pollutants from wastewater. However, most proposed catalysts suffer from low photocatalytic activity due to self-aggregation, structural instability, and limited active sites, which hinder their industrial feasibility. Herein, we report a highly efficient Cu–Fe/WPC catalyst (WPC denotes wood-converted porous carbon) featuring HMOF-derived Cu-Fe bimetallic nanoparticles embedded in the WPC skeleton. Under optimal conditions, the Cu-Fe/WPC/H₂O₂/UV system exhibits exceptional degradation performance for methylene blue (MB) and sulfamethoxazole (SMX), with rapid pseudo-first-order rate constants of 1.397 and 1.489 min⁻¹, respectively. Notably, this hybrid photocatalyst achieves complete degradation of MB and SMX within 5 min. The synergistic catalysis between Fe and Cu dual active sites plays a crucial role in enhancing photo-Fenton activity. This synergy boosts the electron-transfer capacity during the valence-state evolution of copper and accelerates the Fe (III)/Fe (II) redox cycle in the Fenton reaction. Additionally, the conversion of Fe species in the Cu-Fe/WPC/H₂O₂ system dominates H₂O₂ activation, generating abundant hydroxyl radicals (·OH) that subsequently participate in the degradation of organic pollutants. This study presents innovative strategies for synthesizing wood-based porous carbon-supported HMOF derivative catalysts designed for ultra-fast photo-Fenton degradation of emerging organic pollutants.