Hybrids of Nickel-histidine Functionalized Graphene Quantum Dots: Fabrication and Non-enzymatic Glucose Sensing

Abstract

In this work, a method of in-situ recombination of Ni2+ with histidine functionalized graphene quantum dots (His-GQDs) was constructed a three-dimensional network porous structure. The collected precipitate complex precursor was oxidized and the NiO-His-GODs were obtained. The NiO-His-GQDs compound was subjected to high-temperature thermal reduction by inert gas to form Ni-His-GQDs. On the one hand, the intimate contact between Ni nanoparticles and His-GQD greatly shortens the gap between the two complexes, resulting in faster electron migration speed; On the other hand, the conductive (Ni)/semiconductor (His-GQDs) catalytic interface can produce Stokes diode-like structures, accelerate the migration rate of holes carriers in the semiconductor, and exhibit good electrocatalytic activity. A Ni-His-GQDs modified electrode as non-enzymatic glucose electrochemical sensor was shown good electrocatalytic activity and anti-interference property. The concentration of glucose was detected by amperometric analysis, and showed a good linear relation in the concentration range of 5.0 × 10-6∼2.0 × 10-3 M. The detection limit (S/N = 3) is 1.7 × 10−6 M. In addition, interference of sodium chloride (NaCl), uric acid (UA), dopamine (DA) and ascorbic acid (AA) was less than 5.0 % in the same conditions indicating that the hybrids modified electrode sensor could be used for the sensitive and selective detection of glucose.