LAUSR

Uniform 3D hierarchical CuO flower-like architectures have been fabricated by a simple and novel surfactant-assisted hydrothermal method. This route included the formation of CuO microflowers in a solution of cupric chloride and sodium hydroxide at 110 °C for 12 h by using cetyltrimethylammonium bromide as surfactant. The obtained CuO samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectrum, scanning electron microscopy, and transmission electron microscopy. These CuO microflowers, with size of about 5–6 µm, were assembled from many nanosheets with a thickness of 30–40 nm. A growth mechanism for the formation of the CuO flower-like architectures was proposed on the basis of time-dependent experiments. The band gap of CuO microflowers was estimated to be 2.19 eV, which showed significant blue-shift compared with that of the bulk. The current synthetic strategy provides a convenient, low-cost, and nontoxic route to prepare 3D architectures of other semiconductors, and it is important for exploring oxide-based micro/nanostructures for applications in micro/nanodevices.