Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States.
Bechtel Innovation Design Center, Purdue University , West Lafayette, Indiana 47907, United States.
ACS Appl Mater Interfaces. 2017 Oct 18;9(41):36409-36416. doi: 10.1021/acsami.7b11683. Epub 2017 Oct 9.
As functionalized 2D materials are incorporated into hybrid materials, ensuring large-area structural control in noncovalently adsorbed films becomes increasingly important. Noncovalent functionalization avoids disrupting electronic structure in 2D materials; however, relatively weak molecular interactions in such monolayers typically reduce stability toward solution processing and other common material handling conditions. Here, we find that controlling substrate temperature during Langmuir-Schaefer conversion of a standing phase monolayer of diynoic amphiphiles on water to a horizontally oriented monolayer on a 2D substrate routinely produces multimicrometer domains, at least an order of magnitude larger than those typically achieved through drop-casting. Following polymerization, these highly ordered monolayers retain their structures during vigorous washing with solvents including water, ethanol, tetrahydrofuran, and toluene. These findings point to a convenient and broadly applicable strategy for noncovalent functionalization of 2D materials in applications that require large-area structural control, for instance, to minimize desorption at defects during subsequent solution processing.
随着功能化二维材料被纳入混合材料，确保非共价吸附膜中大面积的结构控制变得越来越重要。非共价功能化避免了对二维材料电子结构的破坏；然而，这种单层中相对较弱的分子相互作用通常会降低其对溶液处理和其他常见材料处理条件的稳定性。在这里，我们发现控制基底温度在 Langmuir-Schaefer 转换过程中对水相上的二炔基两亲单分子层到二维基底上的水平取向单分子层通常会产生至少一个数量级的多微米畴，这比通过滴铸通常获得的畴大得多。聚合后，这些高度有序的单层在包括水、乙醇、四氢呋喃和甲苯在内的溶剂的剧烈洗涤过程中保持其结构。这些发现为在需要大面积结构控制的应用中，例如在随后的溶液处理过程中最小化缺陷处的解吸，提供了一种方便且广泛适用的二维材料非共价功能化策略。
