Electrochemical Sensing of Bisphenol A on Facet-Tailored TiO2Single Crystals Engineered by Inorganic-Framework Molecular Imprinting Sites

Noble metals, nanostructured carbon, and their hybrids are widely used for electrochemical detection of persistent organic pollutants. However, despite of the rapid detection process and high accuracy, these materials generally suffer from high costs, metallic impurity, heterogeneity, irreversible adsorption and poor sensitivity. Herein, the high-energy {001}-exposed TiO2 single crystals with specific inorganic-framework molecular recognition ability was prepared as the electrode material to detect bisphenol A (BPA), a typical and widely present organic pollutant in the environment. The oxidation peak current was linearly correlated to the BPA concentration from 10.0 nM to 20.0 μM (R2 = 0.9987), with a low detection limit of 3.0 nM (S/N = 3). Furthermore, it exhibited excellent discriminating ability, high anti-interference capacity, and good long-term stability. Its good performance for BPA detection in real environmental samples, including tap water, lake and river waters, domestic wastewater, and municipal sludge, was also demonstrated. This work extends the applications of TiO2 semiconductor and suggests that this material could be used as a highly active, stable, low-cost, and environmentally benign electrode material for electrochemical sensing.