氧分压对Mn-Co-Ni-O纳米结构生长的影响

在脉冲激光沉积（pulsed laser deposition，PLD）法生长氧化物纳米材料的过程中，环境中的氧气对氧化物纳米结构的形成起着至关重要的作用。在溅射了Au纳米层的Si(111)衬底上，采用PLD法在不同氧分压下制备了Mn-Co-Ni-O纳米结构，并用X射线衍射仪（X-ray diffractometer，XRD）和场发射扫描电子显微镜（scanning electron microscope，SEM）表征了Mn-Co-Ni-O的结构特性和表面形貌。研究发现生长温度为750 ℃的Mn-Co-Ni-O微观结构与氧分压密切相关。在较低的氧分压环境下(1 Pa和5 Pa)，Si衬底上生长的Mn-Co-Ni-O纳米锥结构是由Au催化的气–液–固(vapor-liquid-solid，VLS)生长机制控制。当氧分压增加到15 Pa，Mn-Co-Ni-O纳米结构的形态从纳米锥向纳米线转变，该过程是由VLS和气–固(vapor-solid，VS)生长机制共同作用。深入研究Mn-Co-Ni-O纳米结构的生长机制为获得更多的纳米线提供了理论基础。

Effect of oxygen partial pressure on the growth of Mn-Co-Ni-O nanostructures

In the process of pulsed laser deposition (PLD) growth of oxide nanostructures, oxygen in the environment plays an important role in the formation of oxide nanostructures. Mn-Co-Ni-O nanostructures were prepared on Si (111) substrates sputtered with Au nano-layers by PLD method under different oxygen partial pressures, and the structural characteristics and surface morphology of Mn-Co-Ni-O were characterized by X-ray diffractometer (XRD) and field emission scanning electron microscope (FE-SEM). The study finds that the microstructure of Mn-Co-Ni-O grown at 750 °C is closely related to the oxygen partial pressure. At low oxygen partial pressure (1 Pa and 5 Pa), Mn-Co-Ni-O nanoconics grown on Si substrates are controlled by Au-catalyzed vapor liquid solid (VLS) growth mechanism. When the oxygen partial pressure increases to 15 Pa, the morphology of Mn-Co-Ni-O nanostructures changes from nanocones to nanowires, which is caused by the combined effect of VLS and vapor solid (VS) growth mechanism in this process. The in-depth study of the growth mechanism of Mn-Co-Ni-O nanostructures provides a theoretical basis for obtaining more nanowires.