Yang Z, Chiang C-K, Chang H-T
Department of Chemistry, National Taiwan University, Taipei, Taiwan.
Nanotechnology. 2008 Jan 16;19(2):025604. doi: 10.1088/0957-4484/19/02/025604. Epub 2007 Dec 6.
Hollow and filled Cu(2)O nanocubes of about 28 ± 5 nm in edge length with a band gap ∼2.42 eV have been prepared from cupric nitrate in alkaline aqueous solutions containing fructose and ascorbic acid at room temperature. To the best of our knowledge, this simple strategy demonstrates the first example of preparing high-quality Cu(2)O nanocubes (yield>95%) with sizes smaller than 30 nm. By controlling several important experimental parameters such as pH, concentrations of fructose, and molar ratios of fructose/copper (II), different Cu(2)O nanostructures were prepared. The cubic nanostructures were evidenced by the metal shadowing and transmission electron microscope (TEM) images. We confirmed that the Cu(2)O nanocubes were formed from hollow to filled structures by conducting time-evolution TEM measurements. The thus-prepared Cu(2)O nanocubes possess size-dependence absorption and luminescence characteristics; they absorb light at wavelengths 360 and 454 nm and fluoresce at 493 nm (quantum yield 6.6 × 10(-2)%) when excited at 360 nm. A film of Cu(2)O nanocubes provided a photocurrent density of ∼80 mA m(-2) at a biased voltage 3 V under sunlight illumination (100 mW cm(-2)).
在室温下，通过在含有果糖和抗坏血酸的碱性水溶液中利用硝酸铜制备出了边长约为28±5纳米、带隙约为2.42电子伏特的空心和实心氧化亚铜纳米立方体。据我们所知，这种简单策略展示了制备尺寸小于30纳米的高质量氧化亚铜纳米立方体（产率>95%）的首个实例。通过控制诸如pH值、果糖浓度以及果糖/铜（II）的摩尔比等几个重要实验参数，制备出了不同的氧化亚铜纳米结构。立方纳米结构通过金属阴影和透射电子显微镜（TEM）图像得以证实。通过进行时间演化TEM测量，我们证实了氧化亚铜纳米立方体是由空心结构转变为实心结构的。如此制备的氧化亚铜纳米立方体具有尺寸依赖性的吸收和发光特性；当在360纳米处激发时，它们在波长360和454纳米处吸收光，并在493纳米处发出荧光（量子产率为6.6×10⁻²%）。在阳光照射（100毫瓦/平方厘米）下，氧化亚铜纳米立方体薄膜在3伏偏压下提供了约80毫安/平方米的光电流密度。
