Framework-derived Fe2O3/Mn3O4 nanocubes as electrochemical catalyst for simultaneous analysis of Cu(II) and Hg(II)

Exploiting advanced bimetallic oxide as sensing materials for electroanalysis offers new opportunity to improve the electrochemical performance, but still presents a tough challenge. Herein, we synthesized the uniform Fe 2 O 3 /Mn 3 O 4 nanocubes from a framework structure in a facile approach, which were developed as the electrochemical catalyst for individual and simultaneous analysis of Cu(II) and Hg(II) in 0.1 M HAc-NaAc buffer solution (pH5.0). It showed the excellent electrochemical behavior for the simultaneous analysis Cu(II) and Hg(II) with high sensitivities of 69.29 and 190.55 μA μM cm −2 . The corresponding limit of detection values (LODs) were calculated to be 3.94 nM and 1.39 nM, respectively. The excellent electrochemical behavior of Fe 2 O 3 /Mn 3 O 4 could be attributed to the large specific surface area, which could provide a large number of adsorption sites for Cu(II) and Hg(II). Meanwhile, the bimetallic Fe and Mn atoms arranged in the porous nanocubes could offer a synergistic effect and improve the electrochemical activity. Moreover, it could be successfully applied for the simultaneous analysis of Cu(II) and Hg(II) in real water samples with the favorable recovery rate. The results confirmed that the Fe 2 O 3 /Mn 3 O 4 nanocubes could serve as a reliable platform for the simultaneous analysis of Cu(II) and Hg(II).