Selective and efficacious photoelectrochemical detection of ciprofloxacin based on the self-assembly of 2D/2D g-C3N4/Ti3C2 composites

[Display omitted] •We fabricated the Ti3C2 nanosheets adorned on the graphitic carbon nitride (g-C3N4).•g-C3N4/Ti3C2 was successfully applied for the electrochemical detection of ciprofloxacin (CFX).•g-C3N4/Ti3C2 sensor shows a wide linear range (0.4-1000 nM) and low LOD (0.13 nM) for CFX. Photoelectrochemical (PEC) process has been demonstrated to exert enormous potential in the fields of analysis, and the rational design of PEC sensors are vital for the practical applications. In this study, the g-C3N4/Ti3C2 composite was proposed as a photoelectrochemical sensing material for the detection of ciprofloxacin (CFX). Characterization methods proved the formation of g-C3N4/Ti3C2 compounds and their superior optoelectronic performance. Moreover, the measurement of PEC properties exhibited that the introduction of Ti3C2 and visible light would improve the electron migration efficiency and the separation of photogenerated electron-hole pairs, thereby displaying the synergistic effect to promote the photoelectric performance. More importantly, the current density of g-C3N4/Ti3C2 was linearly proportional to the concentration of CFX ranging from 0.4 to 1000 nM, and the detection limit (3S/N) was 0.13 nM. In addition, such a PEC sensor demonstrated long-term stability, good reproducibility and selectivity. Finally, the real commercial sample detection was measured to confirm the possibility of practical applications. Thus, the g-C3N4/Ti3C2 photo-electrocatalyst provides a new method for CFX detection with high selectivity and sensitivity.