Szoszkiewicz Robert, Rogala Maciej, Dąbrowski Paweł
Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland.
Department of Solid State Physics, Faculty of Physics and Applied Informatics, University of Lodz, Pomorska 149/153, 90-236 Lodz, Poland.
Materials (Basel). 2020 Jul 9;13(14):3067. doi: 10.3390/ma13143067.
We report on the MoO oxides and their derivatives on microscopic 2H MoS flakes oxidized in air and high relative humidity at a moderate temperature range below 410 °C. We combine XPS and AFM measurements such as topography, friction, creation of nanoscale ripples and scratches on the MoS flakes deposited on Si substrates. We detect MoO oxides mostly by measuring selected nanomechanical properties of the MoO layer, such as its compressive mechanical stress at the plastic yield. We discuss basal surface coverage of the single MoS flakes by the MoO oxides. We discuss conditions for appearance of all possible MoO oxide derivatives, such as molybdenum(VI) hydroxyoxides and MoO hydrates. Our findings agree with an expected mechanistic switch in thermal oxidation in water vapors vs. air.
我们报道了在低于410°C的适度温度范围内，在空气和高相对湿度条件下氧化的微观2H MoS薄片上的MoO氧化物及其衍生物。我们结合了XPS和AFM测量，如形貌、摩擦力、在沉积在Si衬底上的MoS薄片上产生纳米级波纹和划痕。我们主要通过测量MoO层的选定纳米力学性能，如其在塑性屈服时的压缩机械应力来检测MoO氧化物。我们讨论了MoO氧化物对单个MoS薄片基面的覆盖情况。我们讨论了所有可能的MoO氧化物衍生物出现的条件，如钼(VI)羟基氧化物和MoO水合物。我们的发现与水蒸气和空气中热氧化中预期的机理转变一致。
