N,N-dicarboxymethyl Perylene-diimide-modified CdV2O6 Nanorods for Colorimetric Sensing of H 2 O 2 and Pyrogallol.

The peroxidase-like activity of CdV 2 O 6 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 H 2 O 2 in only 90 s. PDI-CdV 2 O 6 exhibits high stability at elevated temperatures and PDI-CdV 2 O 6 retains more than 70% of its catalytic activity over a wide range of 15 to 60 °C. The catalytic mechanism of PDI-CdV 2 O 6 is ascribed to the synergistic interaction between PDI and CdV 2 O 6 and the generation of •O 2 - radicals. Based on the enhanced peroxidase-like activity of PDI-CdV 2 O 6 , a selective colorimetric sensor has been constructed for H 2 O 2 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 H 2 O 2 in milk and pyrogallol in tap water.