碘与溴官能化对自底向上石墨烯纳米晶生长的影响：扩散的作用
Iodine versus Bromine Functionalization for Bottom-Up Graphene Nanoribbon Growth: Role of Diffusion
摘要：
确定性的自下而上的方法，用于合成原子定义良好的石墨烯纳米带（GNR）在很大程度上依赖于表面催化活化的分子前体中的选定的不稳定键，然后逐步生长聚合和环化脱氢。虽然大多数成功的GNR前体依赖于热不稳定C-Br键的均裂，但较弱C-I键的引入提供了可以在显著较低温度下聚合的单体的途径，从而有助于增加GNR合成工艺的灵活性。扫描隧道显微镜（STM）成像的分子前体，活化的中间体，和聚合物产生的逐步热退火的Br和I取代的前体的人字形GNRs显示，两种前体的聚合在Au（111）在相似的温度下进行。这一观察结果是一致的扩散限制聚合的表面稳定的自由基中间体，出现从均裂的C-Br或C-I键。
英文摘要：
Deterministic bottom-up approaches for synthesizing atomically well-defined graphene nanoribbons (GNRs) largely rely on the surface-catalyzed activation of selected labile bonds in a molecular precursor followed by step growth polymerization and cyclodehydrogenation. While the majority of successful GNR precursors rely on the homolytic cleavage of thermally labile C-Br bonds, the introduction of weaker C-I bonds provides access to monomers that can be polymerized at significantly lower temperatures, thus helping to increase the flexibility of the GNR synthesis process. Scanning tunneling microscopy (STM) imaging of molecular precursors, activated intermediates, and polymers resulting from stepwise thermal annealing of both Br and I substituted precursors for chevron GNRs reveals that the polymerization of both precursors proceeds at similar temperatures on Au(111). This observation is consistent with diffusion-limited polymerization of the surface-stabilized radical intermediates that emerge from homolytic cleavage of either the C-Br or the C-I bonds.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
