Synthesis and characterization of graphene quantum dots/CoNiAl-layered double-hydroxide nanocomposite: Application as a glucose sensor

•The GQDs/CoNiAl-LDH nanocomposite as a novel material was synthesized by an effective and low-cost synthesis process.•The GQDs/CoNiAl-LDH nanocomposite was used to fabricate a glucose electrochemical sensor.•The present sensor has fast amperometric response, low detection limit, wide linear ranges and high sensitivity to glucose..

In the present work, a novel nanocomposite based on the graphene quantum dots and CoNiAl-layered double-hydroxide was successfully synthesized by co-precipitation method. To achieve the morphological, structural and compositional information, the resulted nanocomposite was characterized by scanning electron microscopy X-ray diffraction, thermal gravimetric analysis, Fourier transform infrared spectroscopy, and photoluminescence. Then, the nanocomposite was used as a modifier to fabricate a modified carbon paste electrode as a non-enzymatic sensor for glucose determination. Electrochemical behavior and determination of glucose at the nanocomposite modified carbon paste electrode were investigated by cyclic voltammetry and chronoamperometry methods, respectively. The prepared sensor offered good electrocatalytic properties, fast response time, high reproducibility and stability. At the optimum conditions, the constructed sensor exhibits wide linear range; 0.01-14.0 mM with a detection limit of 6 μM (S/N = 3) and high sensitivity of 48.717 μAmM−1. Finally, the sensor was successfully applied to determine the glucose in real samples which demonstrated its applicability.

Graphical abstractProposed structure of GQDs/CoNiAl-LDH nanocomposite.Download high-res image (168KB)Download full-size image