Chu W G, Wang H F, Guo Y J, Zhang L N, Han Z H, Li Q Q, Fan S S
National Center for Nanoscience and Technology of China, Beijing 100085, PR China.
Inorg Chem. 2009 Feb 2;48(3):1243-9. doi: 10.1021/ic801885c.
We propose a simple and catalyst-free method to grow quasi-aligned single crystalline Cu(3)Mo(2)O(9) nanorods in terms of a mechanism differing from the conventional vapor-solid (VS) and vapor-liquid-solid (VLS) ones for chemical vapor deposition (CVD) methods by directly heating Cu foils in a mixed atmosphere of MoO(3) vapor and air. High quality Cu(3)Mo(2)O(9) nanorods can be simply grown in a temperature range from 450 to 550 degrees C whose diameter, length, and distribution density are dependent on both heating temperature and time. Interestingly, the growth rate at 550 degrees C drops significantly after 6 h. All nanorods grow along the [010] direction. On the basis of a proposed growth model, the nucleation of Cu(3)Mo(2)O(9) nanorods is believed to be governed by formation of initial polycrystalline Cu(x)O protuberances with nanoscale diameters on Cu foils which may act as growth "templates". This novel method can be applied to grow other similar tertiary transition metal oxide nanostructures on substrates with large sizes. Most importantly, these Cu(3)Mo(2)O(9) nanorods decrease the ignition temperature of Printex U model soot from 600 to 438 degrees C, being in between 200 and 450 degrees C of the exhaust of diesel-powered combustion engines, which are therefore expected to be a potential efficient and environmentally friendly catalyst for diesel exhaust combustion.
我们提出了一种简单且无催化剂的方法，通过在MoO₃蒸汽与空气的混合气氛中直接加热铜箔，以一种不同于传统化学气相沉积（CVD）方法的气-固（VS）和气-液-固（VLS）机制来生长准取向的单晶Cu₃Mo₂O₉纳米棒。高质量的Cu₃Mo₂O₉纳米棒可在450至550摄氏度的温度范围内简单地生长，其直径、长度和分布密度取决于加热温度和时间。有趣的是，在550摄氏度下6小时后生长速率显著下降。所有纳米棒均沿[010]方向生长。基于所提出的生长模型，据信Cu₃Mo₂O₉纳米棒的成核受铜箔上纳米级直径的初始多晶CuₓO突起的形成控制，这些突起可能充当生长“模板”。这种新方法可应用于在大尺寸基板上生长其他类似的三元过渡金属氧化物纳米结构。最重要的是，这些Cu₃Mo₂O₉纳米棒将 Printex U 型碳烟的着火温度从600摄氏度降低到438摄氏度，该温度介于柴油发动机排气温度的200至450摄氏度之间，因此有望成为一种潜在的高效且环保的柴油排气燃烧催化剂。
