Synthesis of Au core flower surrounding with sulphur-doped thin Co3O4 shell for enhanced nonenzymatic detection of glucose

This paper reports the synthesis of S-doped thin Co 3 O 4 shell with Au flower as core for nonenzymatic glucose sensing, where Au@Co 3 O 4 was obtained through assembly process triggered by redox reaction of Co 2+ and Au 3+ , and then S was doped into Co 3 O 4 shell via a hydrothermal process. The morphology, composition and structure of Au@Co 3 O 4 -S were characterized by transmission electron microscopy and X-ray diffraction, which showed that the core–shell structure was composed with Au core flower and S-doped thin Co 3 O 4 shell. Electrochemical property of Au@Co 3 O 4 -S toward glucose was explored, and an excellent electrocatalytic performance with a wide linear range of 0.2 μM–3.1 mM, a high sensitivity of 1127.3 μA mM −1 cm −2 and a low detection limit of 0.09 μM (S/N = 3) was obtained, which may be due to that the low conductivity of Co 3 O 4 was mitigated by conductive Au core flower and S doping, therefore making thin Co 3 O 4 shell provide more effective active sites for glucose reaction. Considering such excellent results, Au@Co 3 O 4 -S was proven as a promising material for electrochemical sensing of glucose.