Solution-Liquid-Solid Growth of Inorganic Materials

这个新奖项授予了华盛顿大学的William S. Buhro，由化学部门的先进材料项目和材料研究部门的固态化学项目提供支持。本课题的研究重点是发展液-液-固（SLS）结晶技术，使之成为低温合成非分子无机固体的通用方法。SLS方法的主要特点是纳米尺寸的熔融铟或铟/镓液滴分散在有机金属前驱体溶液中，晶须晶体从中生长。催化的有机金属反应发生在液滴-溶液界面，产物沉积到液滴中的溶液中。液滴变得过饱和，推动晶须生长。本研究的具体目标是：(1)建立SLS生长的详细机制；(2)纳米晶须尺寸的增益控制并产生窄尺寸分布；(3)三元体系中纳米晶须组成的增益控制；(4)研究异质结构纳米晶须的制备；(5)评估SLS生长对III-V型氮化物和II-VI型硫属化合物合成的普遍性。与受前驱体挥发性限制的传统高温方法相比，本研究将探索一种受化学和表面反应性限制的新型低温制备固态材料的机理和范围。由于新方法是动力学驱动的，因此可以期待新的固相。组成和尺寸可控的固态纳米晶须可能在电子和光学应用中很有用。

This new award to William S. Buhro at Washingon University is supported by the Advanced Materials Program in the Chemistry Division and the Solid-State Chemistry Program in the Division of Materials Research. The focus of the research is the development of the Solution-Liquid-Solid (SLS) crystallization technique as a general method for the low-temperature synthesis of nonmolecular inorganic solids. The primary feature of the SLS method is the dispersion of nonometer-size molten Indium or Indium/Gallium droplets in an organometallic precursor solution, from which the whisker crystals grow. Catalyzed organometallic reactions occur at the droplet-solution interface, depositing the products into solution in the droplet. The droplets become supersaturated, driving whisker growth. The specific goals of the research are to (1) establish the detailed mechanism of SLS growth, (2) gain control of nanowhisker sizes and produce narrow size distributions, (3) gain control of nanowhisker compositions in ternary systems, (4) investigate fabrication of heterostructured nanowhiskers, and (5) assess the generality of SLS growth to the synthesis of III-V nitrides and II-VI chalcogenides. This research will explore the mechanism and scope of a new low-temperature route to solid state materials limited by chemical and surface reactivity compared to traditional high temperature methods which are limited by precursor volatility. Since the new method is kinetically driven, new solid phases can be expected. Solid state nanowhiskers of controlled composition and size are likely to be useful in electronic and optical applications.