Natural sporopollenin cooperated with Cu2O for enhancing Fenton-like reaction and insight into its adsorption contributing to the degradation of rhodamine b and methylene blue

The extensive use of refractory organic dyes in the textile, printing, paper, food, and pharmaceutical industries is a significant source of water pollution. In this study, a novel magnetic hollow porous copper-based Fenton-like catalyst using cattail sporopollenin as a skeleton support (CSp/Fe₃O₄-Cu₂O) was developed for the first time for the adsorption and efficient degradation of two refractory organic dyes rhodamine B and methylene blue in aqueous environments. Under the optimal conditions, CSp/Fe₃O₄-Cu₂O showed complete ability to degrade the mixed dyes. The degradation kinetic constant of CSp/Fe₃O₄-Cu₂O increased by 10.57 times compared to the control Fe₃O₄-Cu₂O. The hollow porous structure of cattail sporopollenin (CSp) in CSp/Fe₃O₄-Cu₂O not only adsorbed the dyes, but also promoted the continuous generation of active species by facilitating the redox cycling of Cu²⁺/Cu⁺ through the adsorption of Cu²⁺, which synergistically realized the efficient degradation of mixed dyes. Furthermore, CSp/Fe₃O₄-Cu₂O showed promising application potentials as follows: degradation rates of over 96 % for mixed dyes in a wide pH range of 3.0–11.0; complete degradation of mixed dyes in various water matrices including ultrapure water, tap water, and Songhua River water; and degradation rates of over 98 % for mixed dyes after six consecutive cycles. Overall, the novel Fenton-like catalyst CSp/Fe₃O₄-Cu₂O developed in this study was found to be highly promising for the treatment of organic dye-contaminated water in chemical industries. This study also provided new insight into using the excellent adsorption properties of natural sporopollenin for the Fenton-like catalytic degradation of organic pollutants.