<p>The sulfate radical-based advanced oxidation process (SR-AOP) has garnered significant attention for its high efficiency in degrading refractory organic pollutants in wastewater. Sulfate radicals (SO₄^•−) were typically generated through the activation of persulfate (PS, including PDS and PMS) via thermal, radiative, or catalytic methods. Cuprous oxide (Cu₂O), as a catalyst for persulfate activation, was particularly attractive due to its cost-effectiveness, environmental friendliness and natural abundance. However, the practical application of pristine Cu₂O was hampered by issues such as particle aggregation, susceptibility to oxidation, poor stability and limited catalytic activity. To address these limitations, carbon quantum dots/Cu₂O (CDs/Cu₂O) nanocomposites was constructed to activate peroxydisulfate (PDS) for the degradation of tetracycline (TC). The enhanced catalytic performance was attributed to the formation of an interfacial heterojunction, which facilitated efficient charge separation. Simultaneously, the incorporated CDs serve as an electron reservoir, further suppressing the recombination of charge carriers. Consequently, the CDs/Cu₂O/PDS system exhibited superior activity, achieving a 98.7% removal rate of TC within 30&#xa0;min. Furthermore, the individual and interactive effects of key operational parameters (i.e., initial pH, TC concentration, and PDS dosage) on the degradation efficiency were systematically investigated through experimental design and multivariate analysis. Radical quenching experiments and electron paramagnetic resonance (EPR) measurements confirmed that both hydroxyl radicals (•OH) and sulfate radicals (SO₄^•−) were the primary reactive oxygen species responsible for TC degradation. This work established a novel strategy for utilizing biomass-derived materials to modify metal oxides for enhanced persulfate activation.</p>