Visible-light-driven molecularly imprinted self-powered sensor for atrazine with high sensitivity and selectivity by separating photoanode from recognition element

Abstract

Atrazine (ATZ) is one of the most widely used and highly toxic triazine herbicides in the world. It is of vital significance to realize ATZ detection with high sensitivity, high selectivity and easy on-site feasibility. Herein, assembled with Ti-Fe-O nanotubes (NTs)/Ni(OH)2 photoanode and molecularly imprinted polymer (MIP) functionalized cathode, a novel molecularly imprinted self-powered sensor (SPS) based on visible-light-driven photo fuel cell (PFC) is developed for ATZ. The MIP cathode serves as the recognition element with advantages of low production cost, high mechanical strength and good stability, while the enzyme-free photoanode has excellent visible light activity and particularly catalytic effects on glucose, leading to spontaneously electron generation and driving the whole cell. By using [Fe(CN)6]3− as the electron transfer switch probe, the SPS can sense ATZ rapidly by the change of output power once ATZ is captured by the cathode. Based on the strategy of using typical photoanode with outstanding oxidative catalytic ability for fuel and placing the recognition element on the cathode separately, the proposed SPS demonstrates excellent power generation performance with a maximum open circuit potential (EOCV) of 0.79 V and a maximum output power density (Pmax) of 13.5 μW·cm−2. It shows a wide linear range of 0.002–21.6 ng·mL−1, a low detection limit of 0.61 pg·mL−1, and a prominent selectivity towards ATZ even in the presence of 100-fold interferents. A proof-of-concept for the integration of molecularly imprinted techniques with PFC and the innovative inspiration for wide used of SPS in complicated environmental system has therefore been provided.