Controllable synthesis of six corner star-like Cu2O/PEDOT-MWCNT composites and their performance toward electrochemical glucose sensing

In this study, a novel electrochemical non-enzyme sensing platform for glucose detection was fabricated on the basis of shape-controlled Cu2O six corner star-like microcrystal (SCSM) composite doped with poly(3,4-ethylenedioxythiophene) (PEDOT)-functionalized multi-walled carbon nanotubes (MWCNTs). The scanning electron microscopy and transmission electron microscopy analysis indicate that the Cu2O SCSMs in the composite show a perfect single crystal structure with six arms and they are bounded with {430} and adjacent high-index facets. Thanks to the Cu2O SCSMs with a high density of active sites and enhanced electron transfer ability of PEDOT-MWCNTs, the prepared Cu2O SCSM/PEDOT-MWCNTs exhibit higher electrocatalytic activity toward glucose oxidation compared to the other counterpart electrodes. On the basis of the Cu2O SCSM/PEDOT-MWCNTs composite, the non-enzymatic amperometric sensing of glucose has been successfully realized in 0.1 M NaOH at 0.5 V with a short response time (<4 s), a low detection limit (0.04 μM, S/N = 3) and a wide linear response concentration range of 4.95 × 10−4–0.374 mM and 0.374–3.446 mM. Moreover, the proposed amperometric sensor presents high sensitivity as well as excellent reproducibility, long term stability and selectivity, suggesting the potential applicability of the sensor for glucose detection.