标题： 二硫化钼氧化物纳米薄片中形态结构和柔性化学应变对电输运机制的影响 显示英文标题

标题： The impact of morphological structure and flexo-chemical strains on the electric transport mechanisms in the molybdenum-disulfide-oxide nanoflakes

摘要： 电导机制在硫化钼氧化物（MoSxOy）压片纳米片粉体中被研究，这取决于其含量和结构。 MoSxOy纳米片是通过(NH4)6Mo7O24与尿素在水溶液中的反应制备的，随后进行空气氧化。 烧结后的纳米片厚度为10-20 nm，并自组装成“纳米花”形状的聚集体，形成粉体颗粒。 粉末的化学组成和结构通过XPS、EDS和拉曼光谱进行了研究，结果显示粉末的化学组成和结构因制备条件不同而有所差异。 这些研究揭示了粉末中存在不同形式的MoS2及其氧化物。 这些特性对电荷输运性质有显著影响。 压片MoSxOy纳米片的电流-电压（I-V）曲线显示出类似滞回的行为；此时回路宽度取决于化学组成和结构。 在氧化物/亚砜形式中钼含量最高的情况下观察到了负微分电导。 所有MoSxOy纳米片样品的I-V曲线表现出三种状态的电阻开关以及在切换“开/关”样品上的电压时的长期瞬态充放电，这证明了界面电荷在其电导率中的作用。 为了理论上描述观察到的I-V曲线以及压片MoSxOy纳米片的极性和电荷输运性质，已采用考虑弯折化学场的Landau-Cahn-Hilliard方法。 实验上发现并理论解释的电阻开关和电荷积累特性在忆阻器和高性能超级电容器的应用中前景广阔。 显示英文摘要

摘要： Electric conduction mechanisms are studied in the pressed nanoflake powder of the molybdenum-disulfide-oxide (MoSxOy) depending on their content and structure. The MoSxOy nanoflakes were prepared by reaction of (NH4)6Mo7O24 with thiourea in aqueous solution followed by aerial oxidation. The sintered nanoflakes are 10-20 nm thick and self-assembled in the "nanoflower"-shape aggregates forming powder particles. The chemical composition and structure of the powders were studied by XPS, EDS and Raman spectroscopy, which show that the powders have different chemical composition and structure depending on the preparation conditions. These studies revealed the existence of different forms of MoS2 and its oxides in the powders. These features are impactful on electric transport properties. The current-voltage (I-V) curves of the pressed MoSxOy nanoflakes reveal hysteresis-like behavior; at that the loop width depends on the chemical composition and structure. The negative differential conductivity is observed for the highest content of Mo in oxide/sulfoxide form. The I-V curves of all MoSxOy nanoflake samples manifest the three-state resistive switching and the long-lasting transient charge/discharge on switching "on/off" the voltage across the sample, which evidences the role of interface charges in their conductivity. To describe theoretically the observed I-V curves, polar and electric-transport properties of the pressed MoSxOy nanoflakes, the Landau-Cahn-Hilliard approach considering flexo-chemical field has been used. The revealed experimentally and explained theoretically features of resistive switching and charge accumulation look promising for applications in memristors and high-performance supercapacitors.