School of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019, USA.
Nanotechnology. 2009 Nov 25;20(47):475601. doi: 10.1088/0957-4484/20/47/475601. Epub 2009 Oct 26.
Well-defined faceted inorganic Mo oxide nanocrystals are synthesized in the gas phase using a solid-fed-precursor flame synthesis method. The solid crystals have rectangular cross-section with characteristic size of 10-20 nm and with lengths ranging from 50 nm to a few hundred nanometres. A 1 mm diameter high purity Mo probe introduced in the oxygen-rich part of the flame serves as the material source. A combination of the strong temperature gradient and varying chemical species concentrations within the flame volume provides the ideal conditions for the rapid and direct formation of these unique nanocrystals. Oxidation and evaporation of MoO3 in the oxygen-rich zone are followed by reduction to MoO2 in the lower temperature, more fuel-rich zone. The MoO3 vapours formed are pushed in the direction of the gas flow and transformed into mature well-defined convex polyhedron nanocrystals bounded with six faces resembling rectangular parallelepipeds.
采用固态进料前驱体火焰合成法在气相中合成了具有明确面心结构的无机 Mo 氧化物纳米晶体。这些固态晶体具有 10-20nm 的特征尺寸和 50nm 到数百纳米的长度，呈矩形截面。在火焰富氧区引入直径为 1mm 的高纯 Mo 探针作为材料源。火焰体积内强烈的温度梯度和不断变化的化学物质浓度的结合为这些独特纳米晶体的快速和直接形成提供了理想的条件。MoO3 在富氧区的氧化和蒸发随后在较低温度、更富燃料的区域还原为 MoO2。形成的 MoO3 蒸气被推向气流方向，并转化为成熟的具有六个面的明确凸多面体纳米晶体，这些晶体类似于六面体。
