Si doping and perylene diimide modification contributed to enhancement of peroxidase-like activity of ceria for constructing colorimetric sensing platform of hydroquinone

Exploring nanoenzymes with higher peroxidase-like activity is an important task to construct a fast sensing platform. In this work, Si doping together with organic functional molecule, N, N-dicarboxymethyl Perylenediimide (PDI) modification were employed as effective strategies to promote the peroxidase-like activity of ceria nanoenzymes. Compared with pure CeO2 and Si-CeO2, PDI/Si-CeO2 exhibits the highest peroxidase-like activity together with oxidase-like activity. The catalytic activity of PDI/Si-CeO2 remained more than 90% of its initial activity in pH range of 4.0 similar to 5.0 and higher temperature between 45 degrees C and 60 degrees C. The catalytic mechanism of PDI/Si-CeO2 NCs was from the active species including superoxide free radicals (O-center dot(2)-) and holes (h(+)). The practical application of the proposed colorimetric platform was validated by detecting HQ in real water samples.