Synthesis and size-dependent electrochemical nonenzymatic H2O2 sensing of cuprous oxide nanocubes
Abstract
In this work, we reported an electrochemical approach for the nonenzymatic detection of H2O2 based on a cuprous oxide (Cu2O) nanocube-based sensor. The Cu2O nanocubes were synthesized with controllable sizes from 40 nm to 360 nm through a facile additive-free aqueous solution route at room temperature. The electrocatalytic activities of the Cu2O nanocubes with five different sizes towards H2O2 were systematically explored, and it was found that the electrocatalytic activity was strongly dependent on the size of the Cu2O nanocubes. The cyclic voltammetry and amperometry results show that these Cu2O nanocubes exhibited good electrocatalytic activity with a linear response ranging from 0.5 to 8.5 mM at −0.2 V and a detection limit of 1.61 μM (S/N = 3). Furthermore, the Cu2O nanocubes of five different sizes have good selectivity for H2O2 detection with ascorbic acid (AA), uric acid (UA) and glucose (Glu).