Superior sensitive graphene fiber sensor enabled by constructing multiple nanoembossments for glucose detection

Metal oxides have been extensively investigated in non-enzymatic biosensors for detecting diabetes owing to their electrochemical catalytic properties and excellent stability. However, lower conductivity and catalytic activity are major obstacles to the commercialization of metal oxide-based non-enzymatic glucose sensors. Herein, we present a novel flexible nonenzymatic glucose sensor utilizing graphene fiber (GF)/Au/Ni(OH)₂ composite fiber. The integration of GFs enables a significant uptake of sensing molecules due to its expansive surface area and high electron mobility, ultimately resulting in a decrease in the detection limit. Consequently, the incorporation of Ni(OH)₂ provides abundant attachment sites by introducing Au atoms, thereby promoting electron migration and enhancing sensitivity and detection limits. An impressive sensitivity (1095.63 µA mM^-1 cm^-2) within the detection range (5 µM-2.2 mM) of the integrated GF/Au/Ni(OH)₂ fiber is achieved, leading to an incredibly low detection limit (0.294 µM). Additionally, the outstanding repeatability, anti-interference properties, and flexibility of the GF/Au/Ni(OH)₂ sensors are obtained as well. Our findings offer a novel method for constructing nano embossments on GFs to achieve superior glucose detection capabilities in the field of wearable electronics in the future.