2D/3D Copper-Based Metal-Organic Frameworks for Electrochemical Detection of Hydrogen Peroxide

Metal-organic frameworks (MOFs) have been extensively used as modified materials of electrochemical sensors in the food industry and agricultural system. In this work, two kinds of copper-based MOFs (Cu-MOFs) with a two dimensional (2D) sheet-like structure and three dimensional (3D) octahedral structure for H2O2 detection were synthesized and compared. The synthesized 2D and 3D Cu-MOFs were modified on the glassy carbon electrode to fabricate electrochemical sensors, respectively. The sensor with 3D Cu-MOF modification (HKUST-1/GCE) presented better electrocatalytic performance than the 2D Cu-MOF modified sensor in H2O2 reduction. Under optimal conditions, the prepared sensor displayed two wide linear ranges of 2 mu M-3 mM and 3-25 mM and a low detection limit of 0.68 mu M. In addition, the 3D Cu-MOF sensor exhibited good selectivity and stability. Furthermore, the prepared HKUST-1/GCE was used for the detection of H2O2 in milk samples with a high recovery rate, indicating great potential and applicability for the detection of substances in food samples. This work provides a convenient, practical, and low-cost route for analysis and extends the application range of MOFs in the food industry, agricultural and environmental systems, and even in the medical field.

Automated summary

In this study, two copper-based MOFs with different structures were synthesized for H2O2 detection, with the 3D Cu-MOF sensor showing superior performance. The prepared sensor exhibited two wide linear ranges, a low detection limit, good selectivity, and stability, showing great potential for substance detection in food samples.