Cu2O nanowires with exposed {111} facet for nonenzymatic detection of glucose in complex biological fluids

Accurate glucose sensing in complex biological fluids could enable diagnostics for home healthcare. However, glucose oxidase (GO x ) has been suffered from poor reproducibility and chemical instability due to intrinsic nature of enzymes. Here, we report a free-standing and robust reduced graphene oxide wrapped Cu foam (rGO/CuF)-supported Cu 2 O nanowires (Cu 2 O NWs) with exposed {111} facet via facile electrodeposition route. When being used as an electrode for nonenzymic glucose detection, Cu 2 O NWs@rGO/CuF exhibited the distinguished performances with powerful reliability for analyzing human plasma and even whole blood samples. These unprecedented performances could be ascribed to nanoscale hydrophilic structure of Cu 2 O NWs, which could control the fouling level especially for protein. Moreover, taking into account the Cu 2 O NWs with exposed {111} facet, Cu 2 O NWs {111} could reduce ion diffusion distance and couple with improved electronic conductivity, thus leading to high glucose sensitivity. Through the theoretical calculations, a reliable interpretation of the catalytic mechanism with Cu 2 O NWs {111} has been provided. This study deepens the understanding of hydrophilic nanostructure and facet-dependent activity of Cu 2 O NWs and points out a strategy to improve their sensitivity and stability.