A highly efficient photoelectrochemical sensor for detection of chlorpyrifos based on 2D/2D β-Bi2O3/g-C3N4 heterojunctions

The development of an effective and stable photochemical sensor is urgently needed to solve the growing environmental pollution problem caused by immoderate usage of an organic phosphorus pesticide named as chlorpyrifos. Under the circumstances, 2D/2D Z-scheme β-Bi2O3/g-C3N4 heterojunctions have been attempted to fabricate the photoelectrochemical sensor, which can detect the chlorpyrifos selectively and sensitively. The 2D/2D intimate contact interfaces could facilitate the separation and migration of electrons-hole pairs. Consquently, β-Bi2O3/g-C3N4 composites possess higher photocurrent response than single β-Bi2O3 and g-C3N4. After the incubation of chlorpyrifos pesticide, in-situ formed Bi-chlorpyrifos complex blocks the transformation of photogenerated charges, and thus contributing to a dramatically decline in photocurrent signal intensity and selective determination of chlorpyrifos. The novel PEC sensor with a strong stability presents a perfect linear relationship between photocurrent intensity and logarithm of chlorpyrifos concentration ranging from 0.01 to 80 ng mL-1, and displays fantabulous properties of a wide linear range and an ideal detection limit of 0.03 ng mL-1 (S/N=3). To some extent, Z-scheme β-Bi2O3/ g-C3N4 sensor is promising for the detection of chlorpyrifos pesticide in practical environmental pollution treatment applications.