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The development of highly efficient and stable photocatalysts is of critical importance for the removal of environmental pollutants, such as paraben preservatives. In this work, carbon quantum dots (CQDs) were used to modify bismuth vanadate (BiVO₄) through a hydrothermal reaction. Regarding the as-formed CQDs/BiVO₄ composite, TEM, XPS, and Raman spectra analysis demonstrated the strong interaction between CQDs and BiVO₄, possibly leading to the elevated energy level of the composite. As compared to pristine BiVO₄, CQDs/BiVO₄ showed an increase in light harvesting, and significantly enhanced visible-light activities in degrading the typical paraben pollutant—benzyl paraben (BzP)—where the maximum 85.4% of BzP was degraded in 150 min. After four cycle reactions, the optimum sample 0.6%CQDs/BiVO₄ still degraded 78.2% of BzP, indicating the good stability and reusability of the composite. The notably higher photocurrent and smaller arc in Nyquist plot were measured by CQDs/BiVO₄, unveiling the improved photocharge separation and lowered interfacial charge transfer resistance by CQDs modification. Meanwhile, due to the promoted energy level, CQDs/BiVO₄ practically produced •O₂⁻ species and thereby contributed to the BzP degradation, while they had no ability to produce •OH. This was contrary to the BiVO₄ system, where •OH and <i>h</i>⁺ played the dominant roles.