Preparation of Cuprous Oxide Mesoporous Spheres with Different Pore Sizes for Non-Enzymatic Glucose Detection

Mass transfer plays a significant role in a sensor's performance, because the substrate can be detected only when it contacts with the active catalytic surface. In this work, cuprous oxide mesoporous nanospheres (Cu2O MPNS) with different pore size distributions are fabricated and applied as electrocatalysts for glucose detection. The small pore Cu2O (SP-Cu2O, mean pore size of 5.3 nm) and large pore Cu2O (LP-Cu2O, mean pore size of 16.4 nm) spheres are prepared by the template method and an etching treatment. The obtained two kinds of Cu2O MPNS exhibit high porosity with a similar specific surface area of 61.2 and 63.4 (m(2).g(-1)), respectively. The prepared Cu2O MPNS are used to construct an electrochemical non-enzymatic glucose sensor. The results show that the LP-Cu2O exhibits better performance than SP-Cu2O, which illustrates that the internal diffusion takes a great impact on the performance of the sensor. The LP-Cu2O modified electrode possesses a high and reproducible sensitivity of 2116.9 mu A mM(-1).cm(-2) at the applied potential of 0.6 V with a wide detection range of 0.003-7.8 mM and a low detection limit of 0.42 mu M.