Department of Chemical and Environmental Sciences, University of Limerick, Ireland.
Langmuir. 2011 Sep 6;27(17):11166-73. doi: 10.1021/la2020868. Epub 2011 Jul 26.
Colloidal carbon spheres were synthesized by the carbonization of squalane, a nonvolatile hydrocarbon solvent, in supercritical carbon dioxide. Precise pressure modulation of the fluid medium led to size controlled growth of carbon spheres ranging from 300 to 1500 nm in diameter. This unique synthetic approach of carbonizing a hydrocarbon suspension in supercritical fluid is found to suppress any particle aggregation, resulting in excellent sphere monodispersity. Core-shell hybrid structures of C-Ge were subsequently formed by inducing the growth of 10-40 nm sized germanium nanocrystals from the spheres in a hierarchical bottom-up approach. Extensive characterization of the spheres and nanocrystals was conducted using transmission and scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman, and thermogravametric analysis. Assemblies of nanocrystal modified carbon colloids impart outstanding superhydrophobic properties due to the combined nano- and microstructuring of the particle arrays.
胶状碳球通过角鲨烷（一种非挥发性碳氢化合物溶剂）在超临界二氧化碳中的碳化反应合成。精确地调节流体介质的压力可以控制碳球的生长，其直径范围从 300 纳米到 1500 纳米不等。这种在超临界流体中碳化碳氢化合物悬浮液的独特合成方法可以抑制任何颗粒聚集，从而得到极好的单分散性球体。随后，通过在分级自下而上的方法中从球体中诱导生长 10-40nm 大小的锗纳米晶体，形成了 C-Ge 核壳混合结构。通过透射电子显微镜和扫描电子显微镜、X 射线衍射、X 射线光电子能谱、拉曼和热重分析对球体和纳米晶体进行了广泛的表征。由于颗粒阵列的纳米和微结构的结合，纳米晶体修饰碳胶体的组装赋予了其优异的超疏水性。
