CoNi–MOF–Graphene Magnetic Nanocomposites for the Electrocatalytic Detection of Glucose and the Efficient Removal of Organic Dyes

The design of a nanocomposite with electrocatalytic activity and recyclable development for the detection of small biomolecules and the removal of environmental pollutants has received enormous attention. A magnetic nanocomposite was synthesized by the hydrothermal approach comprising two building units: metal–organic frameworks (MOFs) and graphene (GR). GR accumulated organic ligands through the large specific surface area and cobalt (Co) and nickel (Ni) served as coordination ions to seamlessly connect with the former for forming CoNi–MOFs–GR (CNMs–GR) to improve the conductivity of MOFs and the electrocatalytic activity of GR. The nanocomposite was utilized to construct an electrochemical sensing platform for the detection of glucose in human blood serum and the removal of organic dyes (methylene blue (MB), congo red (CR), and neutral red (NR)) in water. The CNMs–GR-modified electrode exhibited good electrochemical performance toward glucose in a wide linear range of 10–2900 μM with a detection limit of 1.27 μM. The maximum uptake capacity of CNMs–GR for MB, CR, and NR was 184.29, 912.47, and 894.36 mg/g, respectively. Most obviously, this work provided a strategy for the design of an effective bifunctional nanocomposite, which not only demonstrated the enormous potential for detection of glucose but also realized the removal of organic dyes.