Sensitive photoelectrochemical detection of azomycin on Bi2S3/Bi2WO6 heterojunction using ascorbic acid as a hole-trapping agent

The establishment of an efficient photoelectrochemical (PEC) assay is of great significance for sensitive detection. The Bi 2 S 3 /Bi 2 WO 6 heterojunction is fabricated as photoactive material with the utilization of ascorbic acid (AA) as a hole-trapping agent for PEC sensing azomycin, an emerging antibiotic contaminant. The Bi 2 S 3 /Bi 2 WO 6 shows an intense photocurrent response, which is due to the hierarchical structure for abundant active sites, regulated electron coupling for charge transfer and the suitable band gap for the enhancement of light absorption. The hole-trapping agent AA is used to promote the separation of photogenerated electron-hole pairs and amplify the generated photocurrent signal. The constructed PEC sensor achieves the excellent performance for azomycin detection with a wide linear range and low detection limit, revealing an enormous potential of this strategy as a PEC platform for the sensitive detection of various targets.