Fabrication of hierarchical CuO architectures displaying the (111) facets‐enhanced superior fenton‐like degradation of organic dyes

Three types of hierarchical CuO architectures with the varying (111) facets exposure were controllably fabricated by a microwave-assisted wet chemical route. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy, transmission electron microscopy (TEM), and high-resolution TEM. The results demonstrate that the monoclinic hierarchical pumpkin-like CuO (p-CuO) crystals are self-assembled by 1D nanoribbons primarily exposed (111) lattice planes with diameters of 6–7 nm. Specifically, the XRD peak intensity ratios of I111/I− 111 were calculated to be 1.38 for p-CuO, which is much larger than that of the other shuttle-like CuO (s-CuO) (1.01) and CuO microspheres (m-CuO) (0.92). The possible growth mechanism for the three kinds of CuO microstructures was proposed. Interestingly, it is a finding for the first time that the Fenton-like catalytic activities of the as-prepared CuO catalysts are closely relied on their preferential (111) facets exposure, in which the order of degradation rates of RhB, MB, and MO accords with the following: p-CuO > s-CuO > m-CuO. Significantly, the decoloring efficiency of RhB over p-CuO in the assistant of H2O2 was up to 93.7% within the initial 1 min, and the total removal rate reached 98.5% after 5 min, exhibiting the rapid and superior Fenton-like catalysis activity.