Cu nanoplates with "clean surface": Synthesis and their enhanced biosensors performance.

[Display omitted] • The morphology of Cu was tailored by controlling the ripening time of Cu seeds. • Biosensors by the Cu NPs showed a superior thermostability and sensitivity. • The 2D nanostructure enabled Cu to exhibit a wide detection range toward glucose. • This work would open up a new avenue for utilizing non-noble metals. In this study, we demonstrated a one-pot synthesis of Cu nanoplates (Cu NPs) with high purity and "clean surface". Different from surfactant-assisted method, we tailored the architecture by controlling the ripening time of Cu seeds. Citrate is introduced as a structure-directing agent. Since the "clean surface" provide more available active sites, the as-prepared Cu NPs show a superior performance when utilized in the non-enzymatic biosensors. In the detection of nitrite, the sensor constructed by Cu NPs exhibited a superior sensitivity (303.1 ± 10.18 µA·mM⁻¹·cm⁻²), and the detection range is 5.0 mM. On the contrary, sensitivity for the Cu NPs by surfactant-assisted method is negligible. As applied in the glucose sensors, detection range by Cu NPs could reach 36.0 mM. And the sensitivity under ambient condition (298 K) is 561.93 ± 3.72 µA·mM⁻¹·cm⁻², which is ca. 2.11-folds higher than that for Cu NPs by surfactant-assisted method. In the detection of H 2 O 2 , detection range is 10.0 mM, and the enhancement factor for detection range is up to 2.0-folds. The superior performance can also be extended to the catalysis for the reduction of 4-nitro-phenol. Since no additional noble metals was applied, this strategy would open up a new avenue for utilizing non-noble metals. [ABSTRACT FROM AUTHOR]