Rapid degradation of acid red 88 dye through the construction of Fe-based amorphous/Cu bimetallic composites

Background Fe-based amorphous alloys have attracted increasing attention in wastewater treatment due to their unique atomic structure and catalytic properties; however, their degradation efficiency remains insufficient. This study aims to address this limitation by developing Fe-based amorphous/Cu (Fe am /Cu) composites and evaluating their performance in degrading acid red 88 (AR88). Methods Fe am /Cu bimetallic composites were fabricated via a direct chemical copper plating method. Mechanistic investigations were conducted through XRD, DSC, SEM, XPS, Fe 2+ /Fe 3+ ion addition experiments, inhibition tests, EPR, and LC–MS analyses. Significant Findings Compared with Fe am , the Fe am /Cu composites exhibit significantly enhanced degradation efficiency. This improvement originates from the formation of discontinuous Cu-enriched layer, which generate localized galvanic corrosion with the Fe am matrix, thereby accelerating electron transfer and Fe 2+ /Fe 3+ release while mitigating the influence of metalloids (P, B, and C). Additionally, partial detachment of Cu coatings and selective corrosion expose fresh active sites and increase the specific surface area, enhancing adsorption and catalytic activity. The results indicate that AR88 degradation is mainly governed by the synergistic effects of Fe 2+ /Fe 3+ adsorption–precipitation and the cleavage of azo bonds (–N N–) by reactive species [H]. These findings provide new insights and a feasible strategy for improving the dye degradation performance of Fe-based amorphous alloys.