N,N-dicarboxymethyl Perylene-diimide-modified CdV2O6 Nanorods for Colorimetric Sensing of HO and Pyrogallol.

The peroxidase-like activity of CdVO nanorods has been considerably improved by modification with N, N-dicarboxymethyl perylene-diimide (PDI) as a photosensitizer. The peroxidase-like behaviors are evaluated by virtue of the colorless chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB), which is fast changed into blue oxTMB in the presence of HO in only 90 s. PDI-CdVO exhibits high stability at elevated temperatures and PDI-CdVO retains more than 70% of its catalytic activity over a wide range of 15 to 60 °C. The catalytic mechanism of PDI-CdVO is ascribed to the synergistic interaction between PDI and CdVO and the generation of •O radicals. Based on the enhanced peroxidase-like activity of PDI-CdVO, a selective colorimetric sensor has been constructed for HO and pyrogallol (PG) with detection limits of 36.5 μM and 0.179 μM, respectively. The feasibility of the proposed sensing platform has been validated by detecting HO in milk and pyrogallol in tap water.