ZnO@C Microballs Wrapped with Ni(OH)2 Nanofilms for Electrochemical Sensing of Glucose and Hydrogen Peroxide.

Abstract

Tailor-made metal oxide/hydroxide core-shell structures are promising for the fabrication of effective electrocatalysts. Here, we report the development of a core-shell structure based on carbon-doped and Ni(OH)2 nanofilms wrapped ZnO microballs (NFs-Ni(OH)2 /ZnO@C MBs) for glucose and hydrogen peroxide (H2 O2 ) monitoring. The unique ball-like morphology of the designed structure is achieved through a facile solvothermal strategy by the control of reaction conditions. Typically, ZnO@C MBs offer highly conductive core, and the shell of Ni(OH)2 nanofilms increases the density of catalytic active sites. The interesting morphology and the brilliant electrocatalytic efficacy of designed hybrid, encourage us to design a multi-mode sensor for glucose and H2 O2 screening. The NFs-Ni(OH)2 /ZnO@C MBs/GCE glucose sensor presented good sensitivities (647.899 & 161.550 μA (mmol L-1 )-1 cm-2 ), a quick response (<4 s), lower limit of detection (0.04 μmol L-1 ), and wide detection range (0.004-1.13 & 1.13-5.02 mmol L-1 ). Similarly, the same electrode revealed excellent H2 O2 sensing features including good sensitivities, two linear parts of 3.5-452 and 452-1374 μmol L-1 , and detection limit of 0.03 μmol L-1 as well as high selectivity. Thus, the development of novel hybrid core-shell structure is useful for potential applications in glucose and H2 O2 screening from environmental and physiological samples.