A dandelion-like BiOBr-Bi₂MoO₆-based photoelectrochemical sensor for highly sensitive detection of acetaminophen

Monitoring acetaminophen (AP) in aquatic environments is of great significance for environmental protection and human health, yet simple and sensitive detection of trace AP remains challenging. Herein, a dandelion-like BiOBr-Bi₂MoO₆ composite was synthesized via a hydrothermal method coupled with an in situ growth strategy and employed as the photoactive material to construct a photoelectrochemical (PEC) sensor for sensitive AP detection. Benefiting from the synergistic effects of enhanced charge separation and improved photocurrent stability, the BiOBr-Bi₂MoO₆ composite exhibited superior PEC performance compared with pure BiOBr and Bi₂MoO₆. Under visible-light irradiation, AP acted as an electron donor to consume photogenerated holes, thereby suppressing electron-hole recombination and enhancing the photocurrent response. Under optimized conditions, the proposed PEC sensor exhibited a linear range of 0.06-3.5 μM and a low limit of detection (LOD) of 0.01 μM (S/N = 3). This work provides promising insights for the design of novel photoactive materials and their application in the analysis of biomolecules.