Cu metal-organic framework-derived Cu Nanospheres@Porous carbon/macroporous carbon for electrochemical sensing glucose

Abstract Novel Cu nanospheres@porous carbon firmly arrayed on three-dimensional kenaf stem-derived macroporous carbon (3D-KSCs) integrated electrodes were prepared by simple thermolysis of Cu metal-organic framework (HKUST-1) formed on 3D-KSCs for nonenzymatic glucose sensor. The morphology and catalytic activities of as-obtained Cu nanospheres@porous carbon/3D-KSCs were investigated in detail by various techniques. The results confirmed that some octahedral HKUST-1 were intactly transformed into Cu nanospheres@porous carbon nanocomposites and some HKUST-1 were broken into many uniform small Cu nanospheres@porous carbons on the wall of 3D-KSCs upon thermolysis. The spherical nanostructures were consisted of many Cu nanoparticles embedded into 3D porous carbon frameworks. Since the Cu nanospheres@porous carbon/3D-KSCs integrated electrode has hierarchical pores originated from 3D-KSCs and the porous carbon for mass transfer, excellent electrocatalytic activity resulted from hierarchical and uniformly dispersed Cu nanospheres@porous carbon, the nonenzymatic glucose sensor based on Cu nanospheres@ porous carbon/3D-KSC integrated electrode showed an acceptable linear range of 0.15 μM−5.62 mM, a low detection limit of 0.48 μM and with a sensitivity of as high as 28.67 μA mM -1  cm -2 . The easy and low-cost preparation, hierarchical nanostructures and good electrocatalytic activity of Cu nanospheres@porous carbon/3D-KSCs rendered it promising candidate for sensors and other applications.