Nanoporous gold induced vertically standing 2D NiCo bimetal-organic framework nanosheets for non-enzymatic glucose biosensing

Abstract

Designing new efficient electrocatalysts is of considerable importance for the non-enzymatic electrochemical glucose biosensors development. Herein, novel vertical two-dimensional (2D) NiCo bimetal-organic framework (NiCo-MOF) parallelogrammic nanosheets array is successfully prepared on the surface of nanoporous gold by a bottom-up strategy. Nanopores are essential for directing the vertical growth of 2D-MOF nanosheets and preventing them from stacking to form NiCo-MOF arrays. This vertical allignment feature of nanosheets exposes more accessible active sites and facilates fast mass and charge transport for electrochemical reactions. The strong electron interaction among N, Co, and Ni enhances the electrochemical catalytic oxidation of glucose. 2D NiCo-MOF nanosheets array electrode exhibits high performance for glucose detection with a broad linear ranges of 1 μM to 8 mM, a rapid response time of less than 1 s, a high sensitivity of 0.6844 mA·mM−1 cm−2, and a low detection limit of 0.29 μM. This novel vertical aligned NiCo-MOF nanosheets array is also one kind of promising candidates for multifunctional applications in other fields of energy or catalysis.