Carnation-like Morphology of BiVO<sub>4</sub>-7 Enables Sensitive Photoelectrochemical Determination of Cr(VI) in the Food and Environment
Wenqin Wu,
Zhao Tan,
Xiao Chen,
Xiaomei Chen,
Ling Cheng,
Huimin Wu,
Peiwu Li,
Zhaowei Zhang
Affiliations
Wenqin Wu
Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, National Reference Lab for Biotoxin Test, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China
Zhao Tan
Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, National Reference Lab for Biotoxin Test, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China
Xiao Chen
Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, National Reference Lab for Biotoxin Test, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China
Xiaomei Chen
Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, National Reference Lab for Biotoxin Test, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China
Ling Cheng
Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, National Reference Lab for Biotoxin Test, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China
Huimin Wu
College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China
Peiwu Li
Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, National Reference Lab for Biotoxin Test, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China
Zhaowei Zhang
Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, National Reference Lab for Biotoxin Test, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China
Hexavalent chromium, namely, Cr(VI), is a significant threat to ecological and food safety. Current detection methods are not sensitive to Cr(VI). A photoelectrochemical (PEC) sensor based on bismuth vanadate (BiVO4) was developed for sensitive detection of Cr(VI). First, BiVO4-X (X: the pH of the reaction precursor solution) was synthesized using a facile surfactant-free hydrothermal method. The BiVO4-X morphology was well controlled according to pH values, showing rock-like (X = 1), wrinkled bark-like (X = 4), carnation-like (X = 7), and the collapsed sheet-like morphologies (X = 9, 12). BiVO4-7 exhibited excellent photoelectric performance due to a proper band structure under visible light and a large specific surface area. Then, BiVO4-7 was used to construct a PEC sensor to detect Cr(VI), which was demonstrated to have a low detection limit (10 nM) and wide detection range (2–210 μM). The BiVO4-7 PEC sensor had a stable output signal, as well as excellent reproducibility, repeatability, and selectivity. We used the BiVO4-7 PEC sensor to detect Cr(VI) in real environmental and food samples, resulting in a satisfactory recovery of 90.3–103.0%, as determined by comparison with results obtained using a spectrophotometric method. The BiVO4-7 PEC sensor is promising for practical application to heavy metal detection in the food and environment.
