Enhanced TA determination on 3D flower-like ZnO-Pt nanocomposites under ultraviolet light illumination

Flower-like ZnO-Pt materials with three-dimensional architectures were synthesized by one-pot method, and a novel tannic acid (TA) analytical method based on flower-like ZnO-Pt modified glassy carbon electrode (ZnO-Pt/GCE) was also developed. Due to the introduction of metal Pt on ZnO, the as-prepared electrode exhibited good conductivity and gave rise to a significant increase in the photocurrent density under UV light illumination, confirming an enhanced charge transfer speed and a well combination between exited electron-hole pairs of ZnO. For the analysis of TA, differential pulse voltammetry (DPV) was applied to evaluate the photoelectrochemical performance on ZnO-Pt/GCE, and a wide linear range of 0.04–72.34 μM with a low detection limit of 0.02 μM (at S/N = 3) was obtained ultimately. The oxidation mechanism of tannic acid in different routes was also proposed and discussed. Moreover, the prepared electrode displayed high stability and selectivity toward the determination of tannic acid. These excellent results presented here make the ultraviolet assisted electrochemical determination a promising method in sensing.