Selective and sensitive visible-light-prompt photoelectrochemical sensor of paracetamol based on Bi2WO6 modified with Bi and copper sulfide

Paracetamol (PA) is a ubiquitous non-steroidal anti-inflammatory drug, mainly used to treat headaches, arthritis and osteoarthritis and other diseases. In this work, a novel label free photoelectrochemical (PEC) sensor based on Bi–CuS/Bi2WO6 has been developed for the detection of PA, which was fabricated by a simple two-step hydrothermal process. It was found that Bi–CuS/Bi2WO6 with a CuS/Bi2WO6 heterojunction and surface plasmon resonance (SPR) effect of Bi possesses enhanced charge transfer and absorption wavelengths under visible light, particularly when compared to pristine Bi2WO6 films, thus producing an increase in the observed photocurrent. The photocurrent was increased after adding PA. And the photocurrent increment was linear with PA concentration in the range from 0.01–60 μM with a detection limit of 2.12 nM. Moreover, the PEC sensor also exhibited high anti-interference property and acceptable stability. In the present study, a Bi–CuS/Bi2WO6 photoelectrode is considered a promising candidate for carrying out PEC analysis.