LAUSR

Despite the widespread interest in the examinations of catalytic and facet-dependent properties of Cu2O crystals, it was still difficult to grow ultrasmall Cu2O cubes and octahedra with tunable sizes at a large scale. In this work, CuSO4, NaOH, and sodium ascorbate of varying volumes were added to an aqueous sodium dodecyl sulfate (SDS) solution to generate Cu2O nanocubes with average edge lengths of 16, 25, 29, 36, 51, 63, 72, and 86 nm in just 10 min. Another series of Cu2O cubes with wide size tunability in the range of 27–200 nm is accomplished by simply adjusting the NaOH volume. Similar reaction conditions can also be used to make a large quantity of Cu2O octahedra with opposite corner distances of just 34, 41, and 49 nm. Remarkably, production of these small Cu2O cubes and octahedra is scalable to 500 mL in one reaction. UV–vis absorption and photoluminescence spectra establish their size and facet-dependent optical properties, and a modified band diagram of Cu2O is presented. Recognizing Cu2O nano...