Size-dependent electrochemical properties of copper oxide microchip on sensing of neurochemicals

Since a high impact of nanostructured materials on the electrochemical performance of (bio)sensors has been demonstrated, novel nanostructure engineering strategies in recent years have been developed for the highly efficient catalytic nanomaterials through regulating their morphologies, sizes, and compositions. In this work, non-precious copper oxide (CuO) with a series of controlled sizes were synthesized onto a gold microchip via an electrodeposition method, which was further developed as an electrochemical interface for sensing neuro-chemicals. The dependence of the sizes of CuO ranging from 2.0 mu m to 20 mu m on its electrochemical behaviors was systematically investigated, and various kinds of neurochemicals were analyzed to present a reasonable result. It was found that much higher sensitivity can be achieved at CuO microchips with smaller size (2.0 mu m) towards the neurochemicals, indicating a high impact of size on the electrochemical performance of (bio)sensors. The size-controlled CuO microchip presented a promising reference for the investigation of the size effect on the electrochemical behaviors of (bio)sensors.