Synthesis of nitrogen-doped graphene nanosheets decorated with gold nanoparticles as an improved sensor for electrochemical determination of chloramphenicol

Highlights: • Nitrogen doped graphene decorated with gold nanoparticles were synthesized. • Au nanoparticles improved the surface area and electron transfer properties of N-G. • Au/N-G composite markedly enhanced the voltammetric response of chloramphenicol. • CAP in real sample was successfully determined on Au/N-G modified electrode. -- Abstract: Nitrogen-doped graphene nanosheets decorated with gold nanoparticles (Au/N-G) were synthesized by the reduction of HAuCl4 on the surface of N-G using ethylene glycol as the reducing agent. The surface characterization with various techniques such as scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy showed that many gold nanoparticles were effectively loaded on the surface of N-G via the proposed synthesis process. The impedance analysis indicated that Au/N-G was an excellent electrode material possessing outstanding electrochemical features for electron transfer. Using Au/N-G modified electrode, the electrochemical response of chloramphenicol (CAP) was significantly increased due to the synergetic effect of two nanomaterials. Thus, a high-performance electrochemical sensor for CAP based on Au/N-G was developed