Thermal stress-induced fabrication of carbon micro/nanostructures and the application in high-performance enzyme-free glucose sensors

Abstract

Enzyme-free glucose sensors are of great significance for monitoring patients’ blood glucose, but the fabrication of high performance sensors is still challenging. Carbon micro/nanostructures are good candidates for enzyme-free glucose sensors due to good biocompatibility and conductivity, and highly active surface area. In this study, the formation of flower-like carbon micro/nanostructure arrays by the thermal stress from pyrolysis of suspended micro/nanostructures was studied. The modified carbon microelectromechanical system (C-MEMS) technology involved overexposure of photoresist structures, oxygen plasma etching and pyrolysis processes with stainless steel as substrate. The effects of fabrication parameters like exposure time and width of suspended part to the formation of carbon micro/nanostructures were discussed. The novel carbon micro/nanostructures were integrated with copper oxide (CuO) nanofilm for the application of enzyme-free glucose sensors. The electrochemical performances of CuO nanofilm/carbon micro/nanostructures were characterized, and the results showed that the enzymeless glucose sensors demonstrated excellent specificity, good stability, high sensitivity of (1.09 ± 0.05)×103 μA mM−1 cm−2 and low detection limit of 4.51 ± 0.03 μM. The obtained micro/nanostructures have great potential for high performance micro sensors and on-chip energy storage devices, and the presented approach is promising for large-scale manufacturing of carbon micro/nanostructures.