Using Bismuth Vanadate/Copper Oxide Nanocomposite as Photoelectrochemical Sensor for Naproxen Determination in Sewage

Abstract

Conventional sewage treatment plants are not usually designed to remove emerging contaminants, and this shortcoming leads to the discharge of pharmaceuticals, among other emerging pollutants, into the environment. The present work reports the development of BiVO4/CuO‐based photoelectrochemical sensor for the determination of naproxen in sewage samples. Morphological characterizations were carried out by X‐ray diffraction and Scanning electron microscopy. The band gap energy of the nanocomposite material was calculated by Tauc plots using the data obtained from diffuse reflectance spectroscopy analysis. The sensor presented analytical signal during the photocurrent generation simultaneously with the oxidation of naproxen on the working electrode. The sensor responses were found to be proportional to the increase in naproxen concentration in the linear range of 5 nmol L−1 to 480 nmol L−1, R2=0.996, with a limit of detection of 5 nmol L−1. The presence of naproxen in sewage samples was successfully determined with recovery percentages above 95 %.

Photoelectrochemical biosensing platform for the SARS‐CoV‐2 spike and nucleocapsid proteins

“…Figure 2a presents the SEM image for SrTiO 3 , where it is possible to see agglomerated particles for this material. SEM image for BiVO 4 , presented in Figure 2b, shows irregular particles with different sizes, which is characteristic of the monoclinic BiVO 4 phase- [38,42]. Finally, Figure 2c shows the morphology of the BiVO 4 /SrTiO 3 composite material, which presents agglomerations of small particles of different sizes.…”

Self-Powered Cathodic Photoelectrochemical Aptasensor Comprising a Photocathode and a Photoanode in Microfluidic Analysis Systems

“…Photoelectrochemical (PEC) phenomenon is a process in which light signals that are produced from photochemically active substances excited by light are converted into electrical signals after undergoing charge separation and transfer. , PEC analysis as an important technique with superiorities of low background signal, high sensitivity, simple operation, and wide dynamic response range has been widely employed in environmental monitoring, food safety analysis, and biosensors. − It is generally performed with semiconductor materials including n-type (TiO 2 , BiVO 4 , , and CdS) and p-type (NiO, Cu 2 O, , and PbS) to guarantee the signal output for PEC biosensors. Interestingly, according to the properties of semiconductors, PEC biosensors can be divided into n-type semiconductor-based photoanode sensors and p-type semiconductor-based photocathode sensors.…”