Redox Exfoliation of Layered Transition Metal Dichalcogenides
Redox Exfoliation of Layered Transition Metal Dichalcogenides
复制标题
DOI：
10.1021/acsnano.6b06922
复制
发表时间：
2017-01-01
期刊：
影响因子：
17.1
通讯作者：
Vaia, Richard A.
中科院分区：
文献类型：
--
作者：
Che, Ali Jawaid Justin;Drummy, Lawrence F.;Vaia, Richard A.
过渡金属二卤化物(TMD)由于相对于其他低维纳米材料(如石墨烯、铝硅酸盐)具有广泛的可能性质而在各种应用中引起了相当大的关注。在这里，我们展示了一种替代的方法，在静态的台式条件下，使用温和的氧化还原化学方法剥离V-VII族层状TMD的块状微晶。从边缘位置生成的阴离子多金属氧酸盐物种吸附到TMD表面并产生库仑斥力，从而在不使用剪切力的情况下驱动层分离。这种方法具有通用性(MS2、MSe2和MTe2)，并且与其他基于溶液的方法相比，在制备具有窄层厚分布的高浓度(>；1 mg/mL)分散体方面更快且使用更安全的试剂。最后，展示了这些TMD在一系列溶剂系统中的剥离，这些溶剂系统以前由于巨大的表面能差异而无法获得。这些特性有助于制备高质量的薄膜和整体。
Transition metal dichalcogenides (TMDs) have attracted considerable attention in a diverse array of applications due to the breadth of possible property suites relative to other low-dimensional nanomaterials (e.g., graphene, aluminosilicates). Here, we demonstrate an alternative methodology for the exfoliation of bulk crystallites of group V-VII layered TMDs under quiescent, benchtop conditions using mild redox chemistry. Anionic polyoxometalate species generated from edge sites adsorb to the TMD surface and create Coulombic repulsion that drives layer separation without the use of shear forces. This method is generalizable (MS2, MSe2, and MTe2) and effective in preparing high-concentration (>1 mg/mL) dispersions with narrow layer thickness distributions more rapidly and with safer reagents than alternative solution-based approaches. Finally, exfoliation of these TMDs is demonstrated in a range of solvent systems that were previously inaccessible due to large surface energy differences. These characteristics could be beneficial in the preparation of high-quality films and monoliths.