Au–Nitrogen-Doped Graphene Quantum Dot Composites as “On–Off” Nanosensors for Sensitive Photo-Electrochemical Detection of Caffeic Acid

作者：Qiyuan Zhao, Lin Zhou, Xue Li, Jiaqi He, Weichun Huang, Yan Cai, Jin Wang, Tingting Chen, Yukou Du, Yong Yao · 发表于：Nanomaterials · 年份：2020 · DOI：10.3390/nano10101972 · 被引用次数：14 · 研究领域：Carbon and Quantum Dots Applications、Electrochemical sensors and biosensors、Advanced biosensing and bioanalysis techniques

Herein, gold-nitrogen-doped graphene quantum dot (Au/NGQD) composite modified electrodes were fabricated and applied as "on-off" nanosensors for the photo-electrochemical (PEC) detection of caffeic acid under visible-light irradiation. An effective and simple strategy was established for the preparation of Au/NGQD composites by hydrothermal and calcination methods. Owing to the quantum confinement effect of NGQDs, the local surface plasmon resonance (LSPR) effect of Au nanoparticles (NPs), and the synergistic effect between Au and NGQDs NPs, the Au/NGQDs showed excellent PEC performance, with wide linear concentration ranges (0.11 to 30.25 μM and 30.25 to 280.25 μM), a low detection limit (0.03 μM), excellent sensitivity, and high stability. The present study may provide an advanced strategy for the simple design of Au/NGQD composites to allow their effective application for selective and sensitive sensing of small biological molecules.