Reversible Redox Cycling of Well-Defined, Ultrasmall Cu/Cu2O Nanoparticles
Reversible Redox Cycling of Well-Defined, Ultrasmall Cu/Cu2O Nanoparticles
复制标题
DOI：
10.1021/acsnano.6b07694
复制
发表时间：
2017-03-01
期刊：
影响因子：
17.1
通讯作者：
Shaffer, Milo S. P.
中科院分区：
文献类型：
--
作者：
Pike, Sebastian D.;White, Edward R.;Shaffer, Milo S. P.
通过均三甲基铜(I)分别与H-2或空气反应，合成了非常细小且定义良好的铜(Cu)和铜矿(Cu2O)纳米颗粒(NPs)。在亚化学计量比的配体，即硬脂酸或二(辛基)膦酸(0.1-0.2当量铜)的存在下，制备出直径小至2 nm的超细纳米粒子，可溶于一系列溶剂。铜纳米颗粒的溶液在空气中被定量氧化，形成Cu2O纳米颗粒。利用接近的温度和低氢压(135摄氏度，3bar H-2)，可以将Cu2O NPs还原回Cu(0)NPs。离散的、溶解的铜/铜(I)胶体的这种惊人的可逆氧化还原循环成功地重复了10个循环，代表了19个不同的反应。通过真空转移像差校正的透射电子显微镜、X射线光电子能谱和可见光谱详细研究了在合成和氧化还原循环过程中，配体对纳米粒子的组成和尺寸的影响。
Exceptionally small and well-defined copper (Cu) and cuprite (Cu2O) nanoparticles (NPs) are synthesized by the reaction of mesitylcopper(I) with either H-2 or air, respectively. In the presence of substoichiometric quantities of ligands, namely, stearic or di(octyl)phosphinic acid (0.1-0.2 equiv vs Cu), ultrasmall nanoparticles are prepared with diameters as low as similar to 2 nm, soluble in a range of solvents. The solutions of Cu NPs undergo quantitative oxidation, on exposure to air, to form Cu2O NPs. The Cu2O NPs can be reduced back to Cu(0) NPs using accessible temperatures and low pressures of hydrogen (135 degrees C, 3 bar H-2). This striking reversible redox cycling of the discrete, solubilized Cu/Cu(I) colloids was successfully repeated over 10 cycles, representing 19 separate reactions. The ligands influence the evolution of both composition and size of the nanoparticles, during synthesis and redox cycling, as explored in detail using vacuum-transfer aberration-corrected transmission electron microscopy, X-ray photoelectron spectroscopy, and visible spectroscopy.